Merge remote-tracking branch 'upstream/features' into jonozzz/features

src/_pytest/__init__.py

@@ -0,0 +1,8 @@
+__all__ = ["__version__"]
+
+try:
+    from ._version import version as __version__
+except ImportError:
+    # broken installation, we don't even try
+    # unknown only works because we do poor mans version compare
+    __version__ = "unknown"

src/_pytest/_argcomplete.py

@@ -0,0 +1,107 @@
+
+"""allow bash-completion for argparse with argcomplete if installed
+needs argcomplete>=0.5.6 for python 3.2/3.3 (older versions fail
+to find the magic string, so _ARGCOMPLETE env. var is never set, and
+this does not need special code.
+
+Function try_argcomplete(parser) should be called directly before
+the call to ArgumentParser.parse_args().
+
+The filescompleter is what you normally would use on the positional
+arguments specification, in order to get "dirname/" after "dirn<TAB>"
+instead of the default "dirname ":
+
+   optparser.add_argument(Config._file_or_dir, nargs='*'
+                               ).completer=filescompleter
+
+Other, application specific, completers should go in the file
+doing the add_argument calls as they need to be specified as .completer
+attributes as well. (If argcomplete is not installed, the function the
+attribute points to will not be used).
+
+SPEEDUP
+=======
+The generic argcomplete script for bash-completion
+(/etc/bash_completion.d/python-argcomplete.sh )
+uses a python program to determine startup script generated by pip.
+You can speed up completion somewhat by changing this script to include
+  # PYTHON_ARGCOMPLETE_OK
+so the the python-argcomplete-check-easy-install-script does not
+need to be called to find the entry point of the code and see if that is
+marked  with PYTHON_ARGCOMPLETE_OK
+
+INSTALL/DEBUGGING
+=================
+To include this support in another application that has setup.py generated
+scripts:
+- add the line:
+    # PYTHON_ARGCOMPLETE_OK
+  near the top of the main python entry point
+- include in the file calling parse_args():
+    from _argcomplete import try_argcomplete, filescompleter
+   , call try_argcomplete just before parse_args(), and optionally add
+   filescompleter to the positional arguments' add_argument()
+If things do not work right away:
+- switch on argcomplete debugging with (also helpful when doing custom
+  completers):
+    export _ARC_DEBUG=1
+- run:
+    python-argcomplete-check-easy-install-script $(which appname)
+    echo $?
+  will echo 0 if the magic line has been found, 1 if not
+- sometimes it helps to find early on errors using:
+    _ARGCOMPLETE=1 _ARC_DEBUG=1 appname
+  which should throw a KeyError: 'COMPLINE' (which is properly set by the
+  global argcomplete script).
+"""
+from __future__ import absolute_import, division, print_function
+import sys
+import os
+from glob import glob
+
+
+class FastFilesCompleter(object):
+    "Fast file completer class"
+
+    def __init__(self, directories=True):
+        self.directories = directories
+
+    def __call__(self, prefix, **kwargs):
+        """only called on non option completions"""
+        if os.path.sep in prefix[1:]:
+            prefix_dir = len(os.path.dirname(prefix) + os.path.sep)
+        else:
+            prefix_dir = 0
+        completion = []
+        globbed = []
+        if "*" not in prefix and "?" not in prefix:
+            # we are on unix, otherwise no bash
+            if not prefix or prefix[-1] == os.path.sep:
+                globbed.extend(glob(prefix + ".*"))
+            prefix += "*"
+        globbed.extend(glob(prefix))
+        for x in sorted(globbed):
+            if os.path.isdir(x):
+                x += "/"
+            # append stripping the prefix (like bash, not like compgen)
+            completion.append(x[prefix_dir:])
+        return completion
+
+
+if os.environ.get("_ARGCOMPLETE"):
+    try:
+        import argcomplete.completers
+    except ImportError:
+        sys.exit(-1)
+    filescompleter = FastFilesCompleter()
+
+    def try_argcomplete(parser):
+        argcomplete.autocomplete(parser, always_complete_options=False)
+
+
+else:
+
+    def try_argcomplete(parser):
+        pass
+
+    filescompleter = None

src/_pytest/_code/__init__.py

@@ -0,0 +1,10 @@
+""" python inspection/code generation API """
+from __future__ import absolute_import, division, print_function
+from .code import Code  # noqa
+from .code import ExceptionInfo  # noqa
+from .code import Frame  # noqa
+from .code import Traceback  # noqa
+from .code import getrawcode  # noqa
+from .source import Source  # noqa
+from .source import compile_ as compile  # noqa
+from .source import getfslineno  # noqa

src/_pytest/_code/_py2traceback.py

@@ -0,0 +1,89 @@
+# copied from python-2.7.3's traceback.py
+# CHANGES:
+# - some_str is replaced, trying to create unicode strings
+#
+from __future__ import absolute_import, division, print_function
+import types
+from six import text_type
+
+
+def format_exception_only(etype, value):
+    """Format the exception part of a traceback.
+
+    The arguments are the exception type and value such as given by
+    sys.last_type and sys.last_value. The return value is a list of
+    strings, each ending in a newline.
+
+    Normally, the list contains a single string; however, for
+    SyntaxError exceptions, it contains several lines that (when
+    printed) display detailed information about where the syntax
+    error occurred.
+
+    The message indicating which exception occurred is always the last
+    string in the list.
+
+    """
+
+    # An instance should not have a meaningful value parameter, but
+    # sometimes does, particularly for string exceptions, such as
+    # >>> raise string1, string2  # deprecated
+    #
+    # Clear these out first because issubtype(string1, SyntaxError)
+    # would throw another exception and mask the original problem.
+    if (
+        isinstance(etype, BaseException)
+        or isinstance(etype, types.InstanceType)
+        or etype is None
+        or type(etype) is str
+    ):
+        return [_format_final_exc_line(etype, value)]
+
+    stype = etype.__name__
+
+    if not issubclass(etype, SyntaxError):
+        return [_format_final_exc_line(stype, value)]
+
+    # It was a syntax error; show exactly where the problem was found.
+    lines = []
+    try:
+        msg, (filename, lineno, offset, badline) = value.args
+    except Exception:
+        pass
+    else:
+        filename = filename or "<string>"
+        lines.append('  File "%s", line %d\n' % (filename, lineno))
+        if badline is not None:
+            if isinstance(badline, bytes):  # python 2 only
+                badline = badline.decode("utf-8", "replace")
+            lines.append(u"    %s\n" % badline.strip())
+            if offset is not None:
+                caretspace = badline.rstrip("\n")[:offset].lstrip()
+                # non-space whitespace (likes tabs) must be kept for alignment
+                caretspace = ((c.isspace() and c or " ") for c in caretspace)
+                # only three spaces to account for offset1 == pos 0
+                lines.append("   %s^\n" % "".join(caretspace))
+        value = msg
+
+    lines.append(_format_final_exc_line(stype, value))
+    return lines
+
+
+def _format_final_exc_line(etype, value):
+    """Return a list of a single line -- normal case for format_exception_only"""
+    valuestr = _some_str(value)
+    if value is None or not valuestr:
+        line = "%s\n" % etype
+    else:
+        line = "%s: %s\n" % (etype, valuestr)
+    return line
+
+
+def _some_str(value):
+    try:
+        return text_type(value)
+    except Exception:
+        try:
+            return str(value)
+        except Exception:
+            pass
+    return "<unprintable %s object>" % type(value).__name__

src/_pytest/_code/code.py

@@ -0,0 +1,971 @@
+from __future__ import absolute_import, division, print_function
+import inspect
+import sys
+import traceback
+from inspect import CO_VARARGS, CO_VARKEYWORDS
+
+import attr
+import re
+from weakref import ref
+from _pytest.compat import _PY2, _PY3, PY35, safe_str
+from six import text_type
+import py
+
+builtin_repr = repr
+
+if _PY3:
+    from traceback import format_exception_only
+else:
+    from ._py2traceback import format_exception_only
+
+
+class Code(object):
+    """ wrapper around Python code objects """
+
+    def __init__(self, rawcode):
+        if not hasattr(rawcode, "co_filename"):
+            rawcode = getrawcode(rawcode)
+        try:
+            self.filename = rawcode.co_filename
+            self.firstlineno = rawcode.co_firstlineno - 1
+            self.name = rawcode.co_name
+        except AttributeError:
+            raise TypeError("not a code object: %r" % (rawcode,))
+        self.raw = rawcode
+
+    def __eq__(self, other):
+        return self.raw == other.raw
+
+    __hash__ = None
+
+    def __ne__(self, other):
+        return not self == other
+
+    @property
+    def path(self):
+        """ return a path object pointing to source code (note that it
+        might not point to an actually existing file). """
+        try:
+            p = py.path.local(self.raw.co_filename)
+            # maybe don't try this checking
+            if not p.check():
+                raise OSError("py.path check failed.")
+        except OSError:
+            # XXX maybe try harder like the weird logic
+            # in the standard lib [linecache.updatecache] does?
+            p = self.raw.co_filename
+
+        return p
+
+    @property
+    def fullsource(self):
+        """ return a _pytest._code.Source object for the full source file of the code
+        """
+        from _pytest._code import source
+
+        full, _ = source.findsource(self.raw)
+        return full
+
+    def source(self):
+        """ return a _pytest._code.Source object for the code object's source only
+        """
+        # return source only for that part of code
+        import _pytest._code
+
+        return _pytest._code.Source(self.raw)
+
+    def getargs(self, var=False):
+        """ return a tuple with the argument names for the code object
+
+            if 'var' is set True also return the names of the variable and
+            keyword arguments when present
+        """
+        # handfull shortcut for getting args
+        raw = self.raw
+        argcount = raw.co_argcount
+        if var:
+            argcount += raw.co_flags & CO_VARARGS
+            argcount += raw.co_flags & CO_VARKEYWORDS
+        return raw.co_varnames[:argcount]
+
+
+class Frame(object):
+    """Wrapper around a Python frame holding f_locals and f_globals
+    in which expressions can be evaluated."""
+
+    def __init__(self, frame):
+        self.lineno = frame.f_lineno - 1
+        self.f_globals = frame.f_globals
+        self.f_locals = frame.f_locals
+        self.raw = frame
+        self.code = Code(frame.f_code)
+
+    @property
+    def statement(self):
+        """ statement this frame is at """
+        import _pytest._code
+
+        if self.code.fullsource is None:
+            return _pytest._code.Source("")
+        return self.code.fullsource.getstatement(self.lineno)
+
+    def eval(self, code, **vars):
+        """ evaluate 'code' in the frame
+
+            'vars' are optional additional local variables
+
+            returns the result of the evaluation
+        """
+        f_locals = self.f_locals.copy()
+        f_locals.update(vars)
+        return eval(code, self.f_globals, f_locals)
+
+    def exec_(self, code, **vars):
+        """ exec 'code' in the frame
+
+            'vars' are optiona; additional local variables
+        """
+        f_locals = self.f_locals.copy()
+        f_locals.update(vars)
+        py.builtin.exec_(code, self.f_globals, f_locals)
+
+    def repr(self, object):
+        """ return a 'safe' (non-recursive, one-line) string repr for 'object'
+        """
+        return py.io.saferepr(object)
+
+    def is_true(self, object):
+        return object
+
+    def getargs(self, var=False):
+        """ return a list of tuples (name, value) for all arguments
+
+            if 'var' is set True also include the variable and keyword
+            arguments when present
+        """
+        retval = []
+        for arg in self.code.getargs(var):
+            try:
+                retval.append((arg, self.f_locals[arg]))
+            except KeyError:
+                pass  # this can occur when using Psyco
+        return retval
+
+
+class TracebackEntry(object):
+    """ a single entry in a traceback """
+
+    _repr_style = None
+    exprinfo = None
+
+    def __init__(self, rawentry, excinfo=None):
+        self._excinfo = excinfo
+        self._rawentry = rawentry
+        self.lineno = rawentry.tb_lineno - 1
+
+    def set_repr_style(self, mode):
+        assert mode in ("short", "long")
+        self._repr_style = mode
+
+    @property
+    def frame(self):
+        import _pytest._code
+
+        return _pytest._code.Frame(self._rawentry.tb_frame)
+
+    @property
+    def relline(self):
+        return self.lineno - self.frame.code.firstlineno
+
+    def __repr__(self):
+        return "<TracebackEntry %s:%d>" % (self.frame.code.path, self.lineno + 1)
+
+    @property
+    def statement(self):
+        """ _pytest._code.Source object for the current statement """
+        source = self.frame.code.fullsource
+        return source.getstatement(self.lineno)
+
+    @property
+    def path(self):
+        """ path to the source code """
+        return self.frame.code.path
+
+    def getlocals(self):
+        return self.frame.f_locals
+
+    locals = property(getlocals, None, None, "locals of underlaying frame")
+
+    def getfirstlinesource(self):
+        # on Jython this firstlineno can be -1 apparently
+        return max(self.frame.code.firstlineno, 0)
+
+    def getsource(self, astcache=None):
+        """ return failing source code. """
+        # we use the passed in astcache to not reparse asttrees
+        # within exception info printing
+        from _pytest._code.source import getstatementrange_ast
+
+        source = self.frame.code.fullsource
+        if source is None:
+            return None
+        key = astnode = None
+        if astcache is not None:
+            key = self.frame.code.path
+            if key is not None:
+                astnode = astcache.get(key, None)
+        start = self.getfirstlinesource()
+        try:
+            astnode, _, end = getstatementrange_ast(
+                self.lineno, source, astnode=astnode
+            )
+        except SyntaxError:
+            end = self.lineno + 1
+        else:
+            if key is not None:
+                astcache[key] = astnode
+        return source[start:end]
+
+    source = property(getsource)
+
+    def ishidden(self):
+        """ return True if the current frame has a var __tracebackhide__
+            resolving to True
+
+            If __tracebackhide__ is a callable, it gets called with the
+            ExceptionInfo instance and can decide whether to hide the traceback.
+
+            mostly for internal use
+        """
+        try:
+            tbh = self.frame.f_locals["__tracebackhide__"]
+        except KeyError:
+            try:
+                tbh = self.frame.f_globals["__tracebackhide__"]
+            except KeyError:
+                return False
+
+        if callable(tbh):
+            return tbh(None if self._excinfo is None else self._excinfo())
+        else:
+            return tbh
+
+    def __str__(self):
+        try:
+            fn = str(self.path)
+        except py.error.Error:
+            fn = "???"
+        name = self.frame.code.name
+        try:
+            line = str(self.statement).lstrip()
+        except KeyboardInterrupt:
+            raise
+        except:  # noqa
+            line = "???"
+        return "  File %r:%d in %s\n  %s\n" % (fn, self.lineno + 1, name, line)
+
+    def name(self):
+        return self.frame.code.raw.co_name
+
+    name = property(name, None, None, "co_name of underlaying code")
+
+
+class Traceback(list):
+    """ Traceback objects encapsulate and offer higher level
+        access to Traceback entries.
+    """
+
+    Entry = TracebackEntry
+
+    def __init__(self, tb, excinfo=None):
+        """ initialize from given python traceback object and ExceptionInfo """
+        self._excinfo = excinfo
+        if hasattr(tb, "tb_next"):
+
+            def f(cur):
+                while cur is not None:
+                    yield self.Entry(cur, excinfo=excinfo)
+                    cur = cur.tb_next
+
+            list.__init__(self, f(tb))
+        else:
+            list.__init__(self, tb)
+
+    def cut(self, path=None, lineno=None, firstlineno=None, excludepath=None):
+        """ return a Traceback instance wrapping part of this Traceback
+
+            by provding any combination of path, lineno and firstlineno, the
+            first frame to start the to-be-returned traceback is determined
+
+            this allows cutting the first part of a Traceback instance e.g.
+            for formatting reasons (removing some uninteresting bits that deal
+            with handling of the exception/traceback)
+        """
+        for x in self:
+            code = x.frame.code
+            codepath = code.path
+            if (
+                (path is None or codepath == path)
+                and (
+                    excludepath is None
+                    or not hasattr(codepath, "relto")
+                    or not codepath.relto(excludepath)
+                )
+                and (lineno is None or x.lineno == lineno)
+                and (firstlineno is None or x.frame.code.firstlineno == firstlineno)
+            ):
+                return Traceback(x._rawentry, self._excinfo)
+        return self
+
+    def __getitem__(self, key):
+        val = super(Traceback, self).__getitem__(key)
+        if isinstance(key, type(slice(0))):
+            val = self.__class__(val)
+        return val
+
+    def filter(self, fn=lambda x: not x.ishidden()):
+        """ return a Traceback instance with certain items removed
+
+            fn is a function that gets a single argument, a TracebackEntry
+            instance, and should return True when the item should be added
+            to the Traceback, False when not
+
+            by default this removes all the TracebackEntries which are hidden
+            (see ishidden() above)
+        """
+        return Traceback(filter(fn, self), self._excinfo)
+
+    def getcrashentry(self):
+        """ return last non-hidden traceback entry that lead
+        to the exception of a traceback.
+        """
+        for i in range(-1, -len(self) - 1, -1):
+            entry = self[i]
+            if not entry.ishidden():
+                return entry
+        return self[-1]
+
+    def recursionindex(self):
+        """ return the index of the frame/TracebackEntry where recursion
+            originates if appropriate, None if no recursion occurred
+        """
+        cache = {}
+        for i, entry in enumerate(self):
+            # id for the code.raw is needed to work around
+            # the strange metaprogramming in the decorator lib from pypi
+            # which generates code objects that have hash/value equality
+            # XXX needs a test
+            key = entry.frame.code.path, id(entry.frame.code.raw), entry.lineno
+            # print "checking for recursion at", key
+            values = cache.setdefault(key, [])
+            if values:
+                f = entry.frame
+                loc = f.f_locals
+                for otherloc in values:
+                    if f.is_true(
+                        f.eval(
+                            co_equal,
+                            __recursioncache_locals_1=loc,
+                            __recursioncache_locals_2=otherloc,
+                        )
+                    ):
+                        return i
+            values.append(entry.frame.f_locals)
+        return None
+
+
+co_equal = compile(
+    "__recursioncache_locals_1 == __recursioncache_locals_2", "?", "eval"
+)
+
+
+class ExceptionInfo(object):
+    """ wraps sys.exc_info() objects and offers
+        help for navigating the traceback.
+    """
+
+    _striptext = ""
+    _assert_start_repr = (
+        "AssertionError(u'assert " if _PY2 else "AssertionError('assert "
+    )
+
+    def __init__(self, tup=None, exprinfo=None):
+        import _pytest._code
+
+        if tup is None:
+            tup = sys.exc_info()
+            if exprinfo is None and isinstance(tup[1], AssertionError):
+                exprinfo = getattr(tup[1], "msg", None)
+                if exprinfo is None:
+                    exprinfo = py.io.saferepr(tup[1])
+                if exprinfo and exprinfo.startswith(self._assert_start_repr):
+                    self._striptext = "AssertionError: "
+        self._excinfo = tup
+        #: the exception class
+        self.type = tup[0]
+        #: the exception instance
+        self.value = tup[1]
+        #: the exception raw traceback
+        self.tb = tup[2]
+        #: the exception type name
+        self.typename = self.type.__name__
+        #: the exception traceback (_pytest._code.Traceback instance)
+        self.traceback = _pytest._code.Traceback(self.tb, excinfo=ref(self))
+
+    def __repr__(self):
+        return "<ExceptionInfo %s tblen=%d>" % (self.typename, len(self.traceback))
+
+    def exconly(self, tryshort=False):
+        """ return the exception as a string
+
+            when 'tryshort' resolves to True, and the exception is a
+            _pytest._code._AssertionError, only the actual exception part of
+            the exception representation is returned (so 'AssertionError: ' is
+            removed from the beginning)
+        """
+        lines = format_exception_only(self.type, self.value)
+        text = "".join(lines)
+        text = text.rstrip()
+        if tryshort:
+            if text.startswith(self._striptext):
+                text = text[len(self._striptext) :]
+        return text
+
+    def errisinstance(self, exc):
+        """ return True if the exception is an instance of exc """
+        return isinstance(self.value, exc)
+
+    def _getreprcrash(self):
+        exconly = self.exconly(tryshort=True)
+        entry = self.traceback.getcrashentry()
+        path, lineno = entry.frame.code.raw.co_filename, entry.lineno
+        return ReprFileLocation(path, lineno + 1, exconly)
+
+    def getrepr(
+        self,
+        showlocals=False,
+        style="long",
+        abspath=False,
+        tbfilter=True,
+        funcargs=False,
+    ):
+        """ return str()able representation of this exception info.
+            showlocals: show locals per traceback entry
+            style: long|short|no|native traceback style
+            tbfilter: hide entries (where __tracebackhide__ is true)
+
+            in case of style==native, tbfilter and showlocals is ignored.
+        """
+        if style == "native":
+            return ReprExceptionInfo(
+                ReprTracebackNative(
+                    traceback.format_exception(
+                        self.type, self.value, self.traceback[0]._rawentry
+                    )
+                ),
+                self._getreprcrash(),
+            )
+
+        fmt = FormattedExcinfo(
+            showlocals=showlocals,
+            style=style,
+            abspath=abspath,
+            tbfilter=tbfilter,
+            funcargs=funcargs,
+        )
+        return fmt.repr_excinfo(self)
+
+    def __str__(self):
+        entry = self.traceback[-1]
+        loc = ReprFileLocation(entry.path, entry.lineno + 1, self.exconly())
+        return str(loc)
+
+    def __unicode__(self):
+        entry = self.traceback[-1]
+        loc = ReprFileLocation(entry.path, entry.lineno + 1, self.exconly())
+        return text_type(loc)
+
+    def match(self, regexp):
+        """
+        Match the regular expression 'regexp' on the string representation of
+        the exception. If it matches then True is returned (so that it is
+        possible to write 'assert excinfo.match()'). If it doesn't match an
+        AssertionError is raised.
+        """
+        __tracebackhide__ = True
+        if not re.search(regexp, str(self.value)):
+            assert 0, "Pattern '{!s}' not found in '{!s}'".format(regexp, self.value)
+        return True
+
+
+@attr.s
+class FormattedExcinfo(object):
+    """ presenting information about failing Functions and Generators. """
+
+    # for traceback entries
+    flow_marker = ">"
+    fail_marker = "E"
+
+    showlocals = attr.ib(default=False)
+    style = attr.ib(default="long")
+    abspath = attr.ib(default=True)
+    tbfilter = attr.ib(default=True)
+    funcargs = attr.ib(default=False)
+    astcache = attr.ib(default=attr.Factory(dict), init=False, repr=False)
+
+    def _getindent(self, source):
+        # figure out indent for given source
+        try:
+            s = str(source.getstatement(len(source) - 1))
+        except KeyboardInterrupt:
+            raise
+        except:  # noqa
+            try:
+                s = str(source[-1])
+            except KeyboardInterrupt:
+                raise
+            except:  # noqa
+                return 0
+        return 4 + (len(s) - len(s.lstrip()))
+
+    def _getentrysource(self, entry):
+        source = entry.getsource(self.astcache)
+        if source is not None:
+            source = source.deindent()
+        return source
+
+    def _saferepr(self, obj):
+        return py.io.saferepr(obj)
+
+    def repr_args(self, entry):
+        if self.funcargs:
+            args = []
+            for argname, argvalue in entry.frame.getargs(var=True):
+                args.append((argname, self._saferepr(argvalue)))
+            return ReprFuncArgs(args)
+
+    def get_source(self, source, line_index=-1, excinfo=None, short=False):
+        """ return formatted and marked up source lines. """
+        import _pytest._code
+
+        lines = []
+        if source is None or line_index >= len(source.lines):
+            source = _pytest._code.Source("???")
+            line_index = 0
+        if line_index < 0:
+            line_index += len(source)
+        space_prefix = "    "
+        if short:
+            lines.append(space_prefix + source.lines[line_index].strip())
+        else:
+            for line in source.lines[:line_index]:
+                lines.append(space_prefix + line)
+            lines.append(self.flow_marker + "   " + source.lines[line_index])
+            for line in source.lines[line_index + 1 :]:
+                lines.append(space_prefix + line)
+        if excinfo is not None:
+            indent = 4 if short else self._getindent(source)
+            lines.extend(self.get_exconly(excinfo, indent=indent, markall=True))
+        return lines
+
+    def get_exconly(self, excinfo, indent=4, markall=False):
+        lines = []
+        indent = " " * indent
+        # get the real exception information out
+        exlines = excinfo.exconly(tryshort=True).split("\n")
+        failindent = self.fail_marker + indent[1:]
+        for line in exlines:
+            lines.append(failindent + line)
+            if not markall:
+                failindent = indent
+        return lines
+
+    def repr_locals(self, locals):
+        if self.showlocals:
+            lines = []
+            keys = [loc for loc in locals if loc[0] != "@"]
+            keys.sort()
+            for name in keys:
+                value = locals[name]
+                if name == "__builtins__":
+                    lines.append("__builtins__ = <builtins>")
+                else:
+                    # This formatting could all be handled by the
+                    # _repr() function, which is only reprlib.Repr in
+                    # disguise, so is very configurable.
+                    str_repr = self._saferepr(value)
+                    # if len(str_repr) < 70 or not isinstance(value,
+                    #                            (list, tuple, dict)):
+                    lines.append("%-10s = %s" % (name, str_repr))
+                    # else:
+                    #    self._line("%-10s =\\" % (name,))
+                    #    # XXX
+                    #    pprint.pprint(value, stream=self.excinfowriter)
+            return ReprLocals(lines)
+
+    def repr_traceback_entry(self, entry, excinfo=None):
+        import _pytest._code
+
+        source = self._getentrysource(entry)
+        if source is None:
+            source = _pytest._code.Source("???")
+            line_index = 0
+        else:
+            # entry.getfirstlinesource() can be -1, should be 0 on jython
+            line_index = entry.lineno - max(entry.getfirstlinesource(), 0)
+
+        lines = []
+        style = entry._repr_style
+        if style is None:
+            style = self.style
+        if style in ("short", "long"):
+            short = style == "short"
+            reprargs = self.repr_args(entry) if not short else None
+            s = self.get_source(source, line_index, excinfo, short=short)
+            lines.extend(s)
+            if short:
+                message = "in %s" % (entry.name)
+            else:
+                message = excinfo and excinfo.typename or ""
+            path = self._makepath(entry.path)
+            filelocrepr = ReprFileLocation(path, entry.lineno + 1, message)
+            localsrepr = None
+            if not short:
+                localsrepr = self.repr_locals(entry.locals)
+            return ReprEntry(lines, reprargs, localsrepr, filelocrepr, style)
+        if excinfo:
+            lines.extend(self.get_exconly(excinfo, indent=4))
+        return ReprEntry(lines, None, None, None, style)
+
+    def _makepath(self, path):
+        if not self.abspath:
+            try:
+                np = py.path.local().bestrelpath(path)
+            except OSError:
+                return path
+            if len(np) < len(str(path)):
+                path = np
+        return path
+
+    def repr_traceback(self, excinfo):
+        traceback = excinfo.traceback
+        if self.tbfilter:
+            traceback = traceback.filter()
+
+        if is_recursion_error(excinfo):
+            traceback, extraline = self._truncate_recursive_traceback(traceback)
+        else:
+            extraline = None
+
+        last = traceback[-1]
+        entries = []
+        for index, entry in enumerate(traceback):
+            einfo = (last == entry) and excinfo or None
+            reprentry = self.repr_traceback_entry(entry, einfo)
+            entries.append(reprentry)
+        return ReprTraceback(entries, extraline, style=self.style)
+
+    def _truncate_recursive_traceback(self, traceback):
+        """
+        Truncate the given recursive traceback trying to find the starting point
+        of the recursion.
+
+        The detection is done by going through each traceback entry and finding the
+        point in which the locals of the frame are equal to the locals of a previous frame (see ``recursionindex()``.
+
+        Handle the situation where the recursion process might raise an exception (for example
+        comparing numpy arrays using equality raises a TypeError), in which case we do our best to
+        warn the user of the error and show a limited traceback.
+        """
+        try:
+            recursionindex = traceback.recursionindex()
+        except Exception as e:
+            max_frames = 10
+            extraline = (
+                "!!! Recursion error detected, but an error occurred locating the origin of recursion.\n"
+                "  The following exception happened when comparing locals in the stack frame:\n"
+                "    {exc_type}: {exc_msg}\n"
+                "  Displaying first and last {max_frames} stack frames out of {total}."
+            ).format(
+                exc_type=type(e).__name__,
+                exc_msg=safe_str(e),
+                max_frames=max_frames,
+                total=len(traceback),
+            )
+            traceback = traceback[:max_frames] + traceback[-max_frames:]
+        else:
+            if recursionindex is not None:
+                extraline = "!!! Recursion detected (same locals & position)"
+                traceback = traceback[: recursionindex + 1]
+            else:
+                extraline = None
+
+        return traceback, extraline
+
+    def repr_excinfo(self, excinfo):
+        if _PY2:
+            reprtraceback = self.repr_traceback(excinfo)
+            reprcrash = excinfo._getreprcrash()
+
+            return ReprExceptionInfo(reprtraceback, reprcrash)
+        else:
+            repr_chain = []
+            e = excinfo.value
+            descr = None
+            while e is not None:
+                if excinfo:
+                    reprtraceback = self.repr_traceback(excinfo)
+                    reprcrash = excinfo._getreprcrash()
+                else:
+                    # fallback to native repr if the exception doesn't have a traceback:
+                    # ExceptionInfo objects require a full traceback to work
+                    reprtraceback = ReprTracebackNative(
+                        traceback.format_exception(type(e), e, None)
+                    )
+                    reprcrash = None
+
+                repr_chain += [(reprtraceback, reprcrash, descr)]
+                if e.__cause__ is not None:
+                    e = e.__cause__
+                    excinfo = (
+                        ExceptionInfo((type(e), e, e.__traceback__))
+                        if e.__traceback__
+                        else None
+                    )
+                    descr = "The above exception was the direct cause of the following exception:"
+                elif e.__context__ is not None and not e.__suppress_context__:
+                    e = e.__context__
+                    excinfo = (
+                        ExceptionInfo((type(e), e, e.__traceback__))
+                        if e.__traceback__
+                        else None
+                    )
+                    descr = "During handling of the above exception, another exception occurred:"
+                else:
+                    e = None
+            repr_chain.reverse()
+            return ExceptionChainRepr(repr_chain)
+
+
+class TerminalRepr(object):
+    def __str__(self):
+        s = self.__unicode__()
+        if _PY2:
+            s = s.encode("utf-8")
+        return s
+
+    def __unicode__(self):
+        # FYI this is called from pytest-xdist's serialization of exception
+        # information.
+        io = py.io.TextIO()
+        tw = py.io.TerminalWriter(file=io)
+        self.toterminal(tw)
+        return io.getvalue().strip()
+
+    def __repr__(self):
+        return "<%s instance at %0x>" % (self.__class__, id(self))
+
+
+class ExceptionRepr(TerminalRepr):
+    def __init__(self):
+        self.sections = []
+
+    def addsection(self, name, content, sep="-"):
+        self.sections.append((name, content, sep))
+
+    def toterminal(self, tw):
+        for name, content, sep in self.sections:
+            tw.sep(sep, name)
+            tw.line(content)
+
+
+class ExceptionChainRepr(ExceptionRepr):
+    def __init__(self, chain):
+        super(ExceptionChainRepr, self).__init__()
+        self.chain = chain
+        # reprcrash and reprtraceback of the outermost (the newest) exception
+        # in the chain
+        self.reprtraceback = chain[-1][0]
+        self.reprcrash = chain[-1][1]
+
+    def toterminal(self, tw):
+        for element in self.chain:
+            element[0].toterminal(tw)
+            if element[2] is not None:
+                tw.line("")
+                tw.line(element[2], yellow=True)
+        super(ExceptionChainRepr, self).toterminal(tw)
+
+
+class ReprExceptionInfo(ExceptionRepr):
+    def __init__(self, reprtraceback, reprcrash):
+        super(ReprExceptionInfo, self).__init__()
+        self.reprtraceback = reprtraceback
+        self.reprcrash = reprcrash
+
+    def toterminal(self, tw):
+        self.reprtraceback.toterminal(tw)
+        super(ReprExceptionInfo, self).toterminal(tw)
+
+
+class ReprTraceback(TerminalRepr):
+    entrysep = "_ "
+
+    def __init__(self, reprentries, extraline, style):
+        self.reprentries = reprentries
+        self.extraline = extraline
+        self.style = style
+
+    def toterminal(self, tw):
+        # the entries might have different styles
+        for i, entry in enumerate(self.reprentries):
+            if entry.style == "long":
+                tw.line("")
+            entry.toterminal(tw)
+            if i < len(self.reprentries) - 1:
+                next_entry = self.reprentries[i + 1]
+                if (
+                    entry.style == "long"
+                    or entry.style == "short"
+                    and next_entry.style == "long"
+                ):
+                    tw.sep(self.entrysep)
+
+        if self.extraline:
+            tw.line(self.extraline)
+
+
+class ReprTracebackNative(ReprTraceback):
+    def __init__(self, tblines):
+        self.style = "native"
+        self.reprentries = [ReprEntryNative(tblines)]
+        self.extraline = None
+
+
+class ReprEntryNative(TerminalRepr):
+    style = "native"
+
+    def __init__(self, tblines):
+        self.lines = tblines
+
+    def toterminal(self, tw):
+        tw.write("".join(self.lines))
+
+
+class ReprEntry(TerminalRepr):
+    localssep = "_ "
+
+    def __init__(self, lines, reprfuncargs, reprlocals, filelocrepr, style):
+        self.lines = lines
+        self.reprfuncargs = reprfuncargs
+        self.reprlocals = reprlocals
+        self.reprfileloc = filelocrepr
+        self.style = style
+
+    def toterminal(self, tw):
+        if self.style == "short":
+            self.reprfileloc.toterminal(tw)
+            for line in self.lines:
+                red = line.startswith("E   ")
+                tw.line(line, bold=True, red=red)
+            # tw.line("")
+            return
+        if self.reprfuncargs:
+            self.reprfuncargs.toterminal(tw)
+        for line in self.lines:
+            red = line.startswith("E   ")
+            tw.line(line, bold=True, red=red)
+        if self.reprlocals:
+            # tw.sep(self.localssep, "Locals")
+            tw.line("")
+            self.reprlocals.toterminal(tw)
+        if self.reprfileloc:
+            if self.lines:
+                tw.line("")
+            self.reprfileloc.toterminal(tw)
+
+    def __str__(self):
+        return "%s\n%s\n%s" % ("\n".join(self.lines), self.reprlocals, self.reprfileloc)
+
+
+class ReprFileLocation(TerminalRepr):
+    def __init__(self, path, lineno, message):
+        self.path = str(path)
+        self.lineno = lineno
+        self.message = message
+
+    def toterminal(self, tw):
+        # filename and lineno output for each entry,
+        # using an output format that most editors unterstand
+        msg = self.message
+        i = msg.find("\n")
+        if i != -1:
+            msg = msg[:i]
+        tw.write(self.path, bold=True, red=True)
+        tw.line(":%s: %s" % (self.lineno, msg))
+
+
+class ReprLocals(TerminalRepr):
+    def __init__(self, lines):
+        self.lines = lines
+
+    def toterminal(self, tw):
+        for line in self.lines:
+            tw.line(line)
+
+
+class ReprFuncArgs(TerminalRepr):
+    def __init__(self, args):
+        self.args = args
+
+    def toterminal(self, tw):
+        if self.args:
+            linesofar = ""
+            for name, value in self.args:
+                ns = "%s = %s" % (safe_str(name), safe_str(value))
+                if len(ns) + len(linesofar) + 2 > tw.fullwidth:
+                    if linesofar:
+                        tw.line(linesofar)
+                    linesofar = ns
+                else:
+                    if linesofar:
+                        linesofar += ", " + ns
+                    else:
+                        linesofar = ns
+            if linesofar:
+                tw.line(linesofar)
+            tw.line("")
+
+
+def getrawcode(obj, trycall=True):
+    """ return code object for given function. """
+    try:
+        return obj.__code__
+    except AttributeError:
+        obj = getattr(obj, "im_func", obj)
+        obj = getattr(obj, "func_code", obj)
+        obj = getattr(obj, "f_code", obj)
+        obj = getattr(obj, "__code__", obj)
+        if trycall and not hasattr(obj, "co_firstlineno"):
+            if hasattr(obj, "__call__") and not inspect.isclass(obj):
+                x = getrawcode(obj.__call__, trycall=False)
+                if hasattr(x, "co_firstlineno"):
+                    return x
+        return obj
+
+
+if PY35:  # RecursionError introduced in 3.5
+
+    def is_recursion_error(excinfo):
+        return excinfo.errisinstance(RecursionError)  # noqa
+
+
+else:
+
+    def is_recursion_error(excinfo):
+        if not excinfo.errisinstance(RuntimeError):
+            return False
+        try:
+            return "maximum recursion depth exceeded" in str(excinfo.value)
+        except UnicodeError:
+            return False

src/_pytest/_code/source.py

@@ -0,0 +1,380 @@
+from __future__ import absolute_import, division, generators, print_function
+
+import ast
+from ast import PyCF_ONLY_AST as _AST_FLAG
+from bisect import bisect_right
+import linecache
+import sys
+import six
+import inspect
+import tokenize
+import py
+
+cpy_compile = compile
+
+
+class Source(object):
+    """ an immutable object holding a source code fragment,
+        possibly deindenting it.
+    """
+
+    _compilecounter = 0
+
+    def __init__(self, *parts, **kwargs):
+        self.lines = lines = []
+        de = kwargs.get("deindent", True)
+        rstrip = kwargs.get("rstrip", True)
+        for part in parts:
+            if not part:
+                partlines = []
+            elif isinstance(part, Source):
+                partlines = part.lines
+            elif isinstance(part, (tuple, list)):
+                partlines = [x.rstrip("\n") for x in part]
+            elif isinstance(part, six.string_types):
+                partlines = part.split("\n")
+                if rstrip:
+                    while partlines:
+                        if partlines[-1].strip():
+                            break
+                        partlines.pop()
+            else:
+                partlines = getsource(part, deindent=de).lines
+            if de:
+                partlines = deindent(partlines)
+            lines.extend(partlines)
+
+    def __eq__(self, other):
+        try:
+            return self.lines == other.lines
+        except AttributeError:
+            if isinstance(other, str):
+                return str(self) == other
+            return False
+
+    __hash__ = None
+
+    def __getitem__(self, key):
+        if isinstance(key, int):
+            return self.lines[key]
+        else:
+            if key.step not in (None, 1):
+                raise IndexError("cannot slice a Source with a step")
+            newsource = Source()
+            newsource.lines = self.lines[key.start : key.stop]
+            return newsource
+
+    def __len__(self):
+        return len(self.lines)
+
+    def strip(self):
+        """ return new source object with trailing
+            and leading blank lines removed.
+        """
+        start, end = 0, len(self)
+        while start < end and not self.lines[start].strip():
+            start += 1
+        while end > start and not self.lines[end - 1].strip():
+            end -= 1
+        source = Source()
+        source.lines[:] = self.lines[start:end]
+        return source
+
+    def putaround(self, before="", after="", indent=" " * 4):
+        """ return a copy of the source object with
+            'before' and 'after' wrapped around it.
+        """
+        before = Source(before)
+        after = Source(after)
+        newsource = Source()
+        lines = [(indent + line) for line in self.lines]
+        newsource.lines = before.lines + lines + after.lines
+        return newsource
+
+    def indent(self, indent=" " * 4):
+        """ return a copy of the source object with
+            all lines indented by the given indent-string.
+        """
+        newsource = Source()
+        newsource.lines = [(indent + line) for line in self.lines]
+        return newsource
+
+    def getstatement(self, lineno):
+        """ return Source statement which contains the
+            given linenumber (counted from 0).
+        """
+        start, end = self.getstatementrange(lineno)
+        return self[start:end]
+
+    def getstatementrange(self, lineno):
+        """ return (start, end) tuple which spans the minimal
+            statement region which containing the given lineno.
+        """
+        if not (0 <= lineno < len(self)):
+            raise IndexError("lineno out of range")
+        ast, start, end = getstatementrange_ast(lineno, self)
+        return start, end
+
+    def deindent(self, offset=None):
+        """ return a new source object deindented by offset.
+            If offset is None then guess an indentation offset from
+            the first non-blank line.  Subsequent lines which have a
+            lower indentation offset will be copied verbatim as
+            they are assumed to be part of multilines.
+        """
+        # XXX maybe use the tokenizer to properly handle multiline
+        #     strings etc.pp?
+        newsource = Source()
+        newsource.lines[:] = deindent(self.lines, offset)
+        return newsource
+
+    def isparseable(self, deindent=True):
+        """ return True if source is parseable, heuristically
+            deindenting it by default.
+        """
+        from parser import suite as syntax_checker
+
+        if deindent:
+            source = str(self.deindent())
+        else:
+            source = str(self)
+        try:
+            # compile(source+'\n', "x", "exec")
+            syntax_checker(source + "\n")
+        except KeyboardInterrupt:
+            raise
+        except Exception:
+            return False
+        else:
+            return True
+
+    def __str__(self):
+        return "\n".join(self.lines)
+
+    def compile(
+        self,
+        filename=None,
+        mode="exec",
+        flag=generators.compiler_flag,
+        dont_inherit=0,
+        _genframe=None,
+    ):
+        """ return compiled code object. if filename is None
+            invent an artificial filename which displays
+            the source/line position of the caller frame.
+        """
+        if not filename or py.path.local(filename).check(file=0):
+            if _genframe is None:
+                _genframe = sys._getframe(1)  # the caller
+            fn, lineno = _genframe.f_code.co_filename, _genframe.f_lineno
+            base = "<%d-codegen " % self._compilecounter
+            self.__class__._compilecounter += 1
+            if not filename:
+                filename = base + "%s:%d>" % (fn, lineno)
+            else:
+                filename = base + "%r %s:%d>" % (filename, fn, lineno)
+        source = "\n".join(self.lines) + "\n"
+        try:
+            co = cpy_compile(source, filename, mode, flag)
+        except SyntaxError:
+            ex = sys.exc_info()[1]
+            # re-represent syntax errors from parsing python strings
+            msglines = self.lines[: ex.lineno]
+            if ex.offset:
+                msglines.append(" " * ex.offset + "^")
+            msglines.append("(code was compiled probably from here: %s)" % filename)
+            newex = SyntaxError("\n".join(msglines))
+            newex.offset = ex.offset
+            newex.lineno = ex.lineno
+            newex.text = ex.text
+            raise newex
+        else:
+            if flag & _AST_FLAG:
+                return co
+            lines = [(x + "\n") for x in self.lines]
+            linecache.cache[filename] = (1, None, lines, filename)
+            return co
+
+
+#
+# public API shortcut functions
+#
+
+
+def compile_(
+    source, filename=None, mode="exec", flags=generators.compiler_flag, dont_inherit=0
+):
+    """ compile the given source to a raw code object,
+        and maintain an internal cache which allows later
+        retrieval of the source code for the code object
+        and any recursively created code objects.
+    """
+    if isinstance(source, ast.AST):
+        # XXX should Source support having AST?
+        return cpy_compile(source, filename, mode, flags, dont_inherit)
+    _genframe = sys._getframe(1)  # the caller
+    s = Source(source)
+    co = s.compile(filename, mode, flags, _genframe=_genframe)
+    return co
+
+
+def getfslineno(obj):
+    """ Return source location (path, lineno) for the given object.
+    If the source cannot be determined return ("", -1)
+    """
+    from .code import Code
+
+    try:
+        code = Code(obj)
+    except TypeError:
+        try:
+            fn = inspect.getsourcefile(obj) or inspect.getfile(obj)
+        except TypeError:
+            return "", -1
+
+        fspath = fn and py.path.local(fn) or None
+        lineno = -1
+        if fspath:
+            try:
+                _, lineno = findsource(obj)
+            except IOError:
+                pass
+    else:
+        fspath = code.path
+        lineno = code.firstlineno
+    assert isinstance(lineno, int)
+    return fspath, lineno
+
+
+#
+# helper functions
+#
+
+
+def findsource(obj):
+    try:
+        sourcelines, lineno = inspect.findsource(obj)
+    except py.builtin._sysex:
+        raise
+    except:  # noqa
+        return None, -1
+    source = Source()
+    source.lines = [line.rstrip() for line in sourcelines]
+    return source, lineno
+
+
+def getsource(obj, **kwargs):
+    from .code import getrawcode
+
+    obj = getrawcode(obj)
+    try:
+        strsrc = inspect.getsource(obj)
+    except IndentationError:
+        strsrc = '"Buggy python version consider upgrading, cannot get source"'
+    assert isinstance(strsrc, str)
+    return Source(strsrc, **kwargs)
+
+
+def deindent(lines, offset=None):
+    if offset is None:
+        for line in lines:
+            line = line.expandtabs()
+            s = line.lstrip()
+            if s:
+                offset = len(line) - len(s)
+                break
+        else:
+            offset = 0
+    if offset == 0:
+        return list(lines)
+    newlines = []
+
+    def readline_generator(lines):
+        for line in lines:
+            yield line + "\n"
+
+    it = readline_generator(lines)
+
+    try:
+        for _, _, (sline, _), (eline, _), _ in tokenize.generate_tokens(
+            lambda: next(it)
+        ):
+            if sline > len(lines):
+                break  # End of input reached
+            if sline > len(newlines):
+                line = lines[sline - 1].expandtabs()
+                if line.lstrip() and line[:offset].isspace():
+                    line = line[offset:]  # Deindent
+                newlines.append(line)
+
+            for i in range(sline, eline):
+                # Don't deindent continuing lines of
+                # multiline tokens (i.e. multiline strings)
+                newlines.append(lines[i])
+    except (IndentationError, tokenize.TokenError):
+        pass
+    # Add any lines we didn't see. E.g. if an exception was raised.
+    newlines.extend(lines[len(newlines) :])
+    return newlines
+
+
+def get_statement_startend2(lineno, node):
+    import ast
+
+    # flatten all statements and except handlers into one lineno-list
+    # AST's line numbers start indexing at 1
+    values = []
+    for x in ast.walk(node):
+        if isinstance(x, (ast.stmt, ast.ExceptHandler)):
+            values.append(x.lineno - 1)
+            for name in ("finalbody", "orelse"):
+                val = getattr(x, name, None)
+                if val:
+                    # treat the finally/orelse part as its own statement
+                    values.append(val[0].lineno - 1 - 1)
+    values.sort()
+    insert_index = bisect_right(values, lineno)
+    start = values[insert_index - 1]
+    if insert_index >= len(values):
+        end = None
+    else:
+        end = values[insert_index]
+    return start, end
+
+
+def getstatementrange_ast(lineno, source, assertion=False, astnode=None):
+    if astnode is None:
+        content = str(source)
+        astnode = compile(content, "source", "exec", 1024)  # 1024 for AST
+
+    start, end = get_statement_startend2(lineno, astnode)
+    # we need to correct the end:
+    # - ast-parsing strips comments
+    # - there might be empty lines
+    # - we might have lesser indented code blocks at the end
+    if end is None:
+        end = len(source.lines)
+
+    if end > start + 1:
+        # make sure we don't span differently indented code blocks
+        # by using the BlockFinder helper used which inspect.getsource() uses itself
+        block_finder = inspect.BlockFinder()
+        # if we start with an indented line, put blockfinder to "started" mode
+        block_finder.started = source.lines[start][0].isspace()
+        it = ((x + "\n") for x in source.lines[start:end])
+        try:
+            for tok in tokenize.generate_tokens(lambda: next(it)):
+                block_finder.tokeneater(*tok)
+        except (inspect.EndOfBlock, IndentationError):
+            end = block_finder.last + start
+        except Exception:
+            pass
+
+    # the end might still point to a comment or empty line, correct it
+    while end:
+        line = source.lines[end - 1].lstrip()
+        if line.startswith("#") or not line:
+            end -= 1
+        else:
+            break
+    return astnode, start, end

src/_pytest/assertion/__init__.py

@@ -0,0 +1,151 @@
+"""
+support for presenting detailed information in failing assertions.
+"""
+from __future__ import absolute_import, division, print_function
+import sys
+import six
+
+from _pytest.assertion import util
+from _pytest.assertion import rewrite
+from _pytest.assertion import truncate
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("debugconfig")
+    group.addoption(
+        "--assert",
+        action="store",
+        dest="assertmode",
+        choices=("rewrite", "plain"),
+        default="rewrite",
+        metavar="MODE",
+        help="""Control assertion debugging tools.  'plain'
+                            performs no assertion debugging.  'rewrite'
+                            (the default) rewrites assert statements in
+                            test modules on import to provide assert
+                            expression information.""",
+    )
+
+
+def register_assert_rewrite(*names):
+    """Register one or more module names to be rewritten on import.
+
+    This function will make sure that this module or all modules inside
+    the package will get their assert statements rewritten.
+    Thus you should make sure to call this before the module is
+    actually imported, usually in your __init__.py if you are a plugin
+    using a package.
+
+    :raise TypeError: if the given module names are not strings.
+    """
+    for name in names:
+        if not isinstance(name, str):
+            msg = "expected module names as *args, got {0} instead"
+            raise TypeError(msg.format(repr(names)))
+    for hook in sys.meta_path:
+        if isinstance(hook, rewrite.AssertionRewritingHook):
+            importhook = hook
+            break
+    else:
+        importhook = DummyRewriteHook()
+    importhook.mark_rewrite(*names)
+
+
+class DummyRewriteHook(object):
+    """A no-op import hook for when rewriting is disabled."""
+
+    def mark_rewrite(self, *names):
+        pass
+
+
+class AssertionState(object):
+    """State for the assertion plugin."""
+
+    def __init__(self, config, mode):
+        self.mode = mode
+        self.trace = config.trace.root.get("assertion")
+        self.hook = None
+
+
+def install_importhook(config):
+    """Try to install the rewrite hook, raise SystemError if it fails."""
+    # Jython has an AST bug that make the assertion rewriting hook malfunction.
+    if sys.platform.startswith("java"):
+        raise SystemError("rewrite not supported")
+
+    config._assertstate = AssertionState(config, "rewrite")
+    config._assertstate.hook = hook = rewrite.AssertionRewritingHook(config)
+    sys.meta_path.insert(0, hook)
+    config._assertstate.trace("installed rewrite import hook")
+
+    def undo():
+        hook = config._assertstate.hook
+        if hook is not None and hook in sys.meta_path:
+            sys.meta_path.remove(hook)
+
+    config.add_cleanup(undo)
+    return hook
+
+
+def pytest_collection(session):
+    # this hook is only called when test modules are collected
+    # so for example not in the master process of pytest-xdist
+    # (which does not collect test modules)
+    assertstate = getattr(session.config, "_assertstate", None)
+    if assertstate:
+        if assertstate.hook is not None:
+            assertstate.hook.set_session(session)
+
+
+def pytest_runtest_setup(item):
+    """Setup the pytest_assertrepr_compare hook
+
+    The newinterpret and rewrite modules will use util._reprcompare if
+    it exists to use custom reporting via the
+    pytest_assertrepr_compare hook.  This sets up this custom
+    comparison for the test.
+    """
+
+    def callbinrepr(op, left, right):
+        """Call the pytest_assertrepr_compare hook and prepare the result
+
+        This uses the first result from the hook and then ensures the
+        following:
+        * Overly verbose explanations are truncated unless configured otherwise
+          (eg. if running in verbose mode).
+        * Embedded newlines are escaped to help util.format_explanation()
+          later.
+        * If the rewrite mode is used embedded %-characters are replaced
+          to protect later % formatting.
+
+        The result can be formatted by util.format_explanation() for
+        pretty printing.
+        """
+        hook_result = item.ihook.pytest_assertrepr_compare(
+            config=item.config, op=op, left=left, right=right
+        )
+        for new_expl in hook_result:
+            if new_expl:
+                new_expl = truncate.truncate_if_required(new_expl, item)
+                new_expl = [line.replace("\n", "\\n") for line in new_expl]
+                res = six.text_type("\n~").join(new_expl)
+                if item.config.getvalue("assertmode") == "rewrite":
+                    res = res.replace("%", "%%")
+                return res
+
+    util._reprcompare = callbinrepr
+
+
+def pytest_runtest_teardown(item):
+    util._reprcompare = None
+
+
+def pytest_sessionfinish(session):
+    assertstate = getattr(session.config, "_assertstate", None)
+    if assertstate:
+        if assertstate.hook is not None:
+            assertstate.hook.set_session(None)
+
+
+# Expose this plugin's implementation for the pytest_assertrepr_compare hook
+pytest_assertrepr_compare = util.assertrepr_compare

src/_pytest/assertion/rewrite.py

@@ -0,0 +1,964 @@
+"""Rewrite assertion AST to produce nice error messages"""
+from __future__ import absolute_import, division, print_function
+import ast
+import errno
+import itertools
+import imp
+import marshal
+import os
+import re
+import six
+import struct
+import sys
+import types
+
+import atomicwrites
+import py
+
+from _pytest.assertion import util
+
+
+# pytest caches rewritten pycs in __pycache__.
+if hasattr(imp, "get_tag"):
+    PYTEST_TAG = imp.get_tag() + "-PYTEST"
+else:
+    if hasattr(sys, "pypy_version_info"):
+        impl = "pypy"
+    elif sys.platform == "java":
+        impl = "jython"
+    else:
+        impl = "cpython"
+    ver = sys.version_info
+    PYTEST_TAG = "%s-%s%s-PYTEST" % (impl, ver[0], ver[1])
+    del ver, impl
+
+PYC_EXT = ".py" + (__debug__ and "c" or "o")
+PYC_TAIL = "." + PYTEST_TAG + PYC_EXT
+
+ASCII_IS_DEFAULT_ENCODING = sys.version_info[0] < 3
+
+if sys.version_info >= (3, 5):
+    ast_Call = ast.Call
+else:
+
+    def ast_Call(a, b, c):
+        return ast.Call(a, b, c, None, None)
+
+
+if sys.version_info >= (3, 4):
+    from importlib.util import spec_from_file_location
+else:
+
+    def spec_from_file_location(*_, **__):
+        return None
+
+
+class AssertionRewritingHook(object):
+    """PEP302 Import hook which rewrites asserts."""
+
+    def __init__(self, config):
+        self.config = config
+        self.fnpats = config.getini("python_files")
+        self.session = None
+        self.modules = {}
+        self._rewritten_names = set()
+        self._register_with_pkg_resources()
+        self._must_rewrite = set()
+
+    def set_session(self, session):
+        self.session = session
+
+    def find_module(self, name, path=None):
+        state = self.config._assertstate
+        state.trace("find_module called for: %s" % name)
+        names = name.rsplit(".", 1)
+        lastname = names[-1]
+        pth = None
+        if path is not None:
+            # Starting with Python 3.3, path is a _NamespacePath(), which
+            # causes problems if not converted to list.
+            path = list(path)
+            if len(path) == 1:
+                pth = path[0]
+        if pth is None:
+            try:
+                fd, fn, desc = imp.find_module(lastname, path)
+            except ImportError:
+                return None
+            if fd is not None:
+                fd.close()
+            tp = desc[2]
+            if tp == imp.PY_COMPILED:
+                if hasattr(imp, "source_from_cache"):
+                    try:
+                        fn = imp.source_from_cache(fn)
+                    except ValueError:
+                        # Python 3 doesn't like orphaned but still-importable
+                        # .pyc files.
+                        fn = fn[:-1]
+                else:
+                    fn = fn[:-1]
+            elif tp != imp.PY_SOURCE:
+                # Don't know what this is.
+                return None
+        else:
+            fn = os.path.join(pth, name.rpartition(".")[2] + ".py")
+
+        fn_pypath = py.path.local(fn)
+        if not self._should_rewrite(name, fn_pypath, state):
+            return None
+
+        self._rewritten_names.add(name)
+
+        # The requested module looks like a test file, so rewrite it. This is
+        # the most magical part of the process: load the source, rewrite the
+        # asserts, and load the rewritten source. We also cache the rewritten
+        # module code in a special pyc. We must be aware of the possibility of
+        # concurrent pytest processes rewriting and loading pycs. To avoid
+        # tricky race conditions, we maintain the following invariant: The
+        # cached pyc is always a complete, valid pyc. Operations on it must be
+        # atomic. POSIX's atomic rename comes in handy.
+        write = not sys.dont_write_bytecode
+        cache_dir = os.path.join(fn_pypath.dirname, "__pycache__")
+        if write:
+            try:
+                os.mkdir(cache_dir)
+            except OSError:
+                e = sys.exc_info()[1].errno
+                if e == errno.EEXIST:
+                    # Either the __pycache__ directory already exists (the
+                    # common case) or it's blocked by a non-dir node. In the
+                    # latter case, we'll ignore it in _write_pyc.
+                    pass
+                elif e in [errno.ENOENT, errno.ENOTDIR]:
+                    # One of the path components was not a directory, likely
+                    # because we're in a zip file.
+                    write = False
+                elif e in [errno.EACCES, errno.EROFS, errno.EPERM]:
+                    state.trace("read only directory: %r" % fn_pypath.dirname)
+                    write = False
+                else:
+                    raise
+        cache_name = fn_pypath.basename[:-3] + PYC_TAIL
+        pyc = os.path.join(cache_dir, cache_name)
+        # Notice that even if we're in a read-only directory, I'm going
+        # to check for a cached pyc. This may not be optimal...
+        co = _read_pyc(fn_pypath, pyc, state.trace)
+        if co is None:
+            state.trace("rewriting %r" % (fn,))
+            source_stat, co = _rewrite_test(self.config, fn_pypath)
+            if co is None:
+                # Probably a SyntaxError in the test.
+                return None
+            if write:
+                _write_pyc(state, co, source_stat, pyc)
+        else:
+            state.trace("found cached rewritten pyc for %r" % (fn,))
+        self.modules[name] = co, pyc
+        return self
+
+    def _should_rewrite(self, name, fn_pypath, state):
+        # always rewrite conftest files
+        fn = str(fn_pypath)
+        if fn_pypath.basename == "conftest.py":
+            state.trace("rewriting conftest file: %r" % (fn,))
+            return True
+
+        if self.session is not None:
+            if self.session.isinitpath(fn):
+                state.trace("matched test file (was specified on cmdline): %r" % (fn,))
+                return True
+
+        # modules not passed explicitly on the command line are only
+        # rewritten if they match the naming convention for test files
+        for pat in self.fnpats:
+            if fn_pypath.fnmatch(pat):
+                state.trace("matched test file %r" % (fn,))
+                return True
+
+        for marked in self._must_rewrite:
+            if name == marked or name.startswith(marked + "."):
+                state.trace("matched marked file %r (from %r)" % (name, marked))
+                return True
+
+        return False
+
+    def mark_rewrite(self, *names):
+        """Mark import names as needing to be rewritten.
+
+        The named module or package as well as any nested modules will
+        be rewritten on import.
+        """
+        already_imported = (
+            set(names).intersection(sys.modules).difference(self._rewritten_names)
+        )
+        for name in already_imported:
+            if not AssertionRewriter.is_rewrite_disabled(
+                sys.modules[name].__doc__ or ""
+            ):
+                self._warn_already_imported(name)
+        self._must_rewrite.update(names)
+
+    def _warn_already_imported(self, name):
+        self.config.warn(
+            "P1", "Module already imported so cannot be rewritten: %s" % name
+        )
+
+    def load_module(self, name):
+        # If there is an existing module object named 'fullname' in
+        # sys.modules, the loader must use that existing module. (Otherwise,
+        # the reload() builtin will not work correctly.)
+        if name in sys.modules:
+            return sys.modules[name]
+
+        co, pyc = self.modules.pop(name)
+        # I wish I could just call imp.load_compiled here, but __file__ has to
+        # be set properly. In Python 3.2+, this all would be handled correctly
+        # by load_compiled.
+        mod = sys.modules[name] = imp.new_module(name)
+        try:
+            mod.__file__ = co.co_filename
+            # Normally, this attribute is 3.2+.
+            mod.__cached__ = pyc
+            mod.__loader__ = self
+            # Normally, this attribute is 3.4+
+            mod.__spec__ = spec_from_file_location(name, co.co_filename, loader=self)
+            py.builtin.exec_(co, mod.__dict__)
+        except:  # noqa
+            if name in sys.modules:
+                del sys.modules[name]
+            raise
+        return sys.modules[name]
+
+    def is_package(self, name):
+        try:
+            fd, fn, desc = imp.find_module(name)
+        except ImportError:
+            return False
+        if fd is not None:
+            fd.close()
+        tp = desc[2]
+        return tp == imp.PKG_DIRECTORY
+
+    @classmethod
+    def _register_with_pkg_resources(cls):
+        """
+        Ensure package resources can be loaded from this loader. May be called
+        multiple times, as the operation is idempotent.
+        """
+        try:
+            import pkg_resources
+
+            # access an attribute in case a deferred importer is present
+            pkg_resources.__name__
+        except ImportError:
+            return
+
+        # Since pytest tests are always located in the file system, the
+        #  DefaultProvider is appropriate.
+        pkg_resources.register_loader_type(cls, pkg_resources.DefaultProvider)
+
+    def get_data(self, pathname):
+        """Optional PEP302 get_data API.
+        """
+        with open(pathname, "rb") as f:
+            return f.read()
+
+
+def _write_pyc(state, co, source_stat, pyc):
+    # Technically, we don't have to have the same pyc format as
+    # (C)Python, since these "pycs" should never be seen by builtin
+    # import. However, there's little reason deviate, and I hope
+    # sometime to be able to use imp.load_compiled to load them. (See
+    # the comment in load_module above.)
+    try:
+        with atomicwrites.atomic_write(pyc, mode="wb", overwrite=True) as fp:
+            fp.write(imp.get_magic())
+            mtime = int(source_stat.mtime)
+            size = source_stat.size & 0xFFFFFFFF
+            fp.write(struct.pack("<ll", mtime, size))
+            fp.write(marshal.dumps(co))
+    except EnvironmentError as e:
+        state.trace("error writing pyc file at %s: errno=%s" % (pyc, e.errno))
+        # we ignore any failure to write the cache file
+        # there are many reasons, permission-denied, __pycache__ being a
+        # file etc.
+        return False
+    return True
+
+
+RN = "\r\n".encode("utf-8")
+N = "\n".encode("utf-8")
+
+cookie_re = re.compile(r"^[ \t\f]*#.*coding[:=][ \t]*[-\w.]+")
+BOM_UTF8 = "\xef\xbb\xbf"
+
+
+def _rewrite_test(config, fn):
+    """Try to read and rewrite *fn* and return the code object."""
+    state = config._assertstate
+    try:
+        stat = fn.stat()
+        source = fn.read("rb")
+    except EnvironmentError:
+        return None, None
+    if ASCII_IS_DEFAULT_ENCODING:
+        # ASCII is the default encoding in Python 2. Without a coding
+        # declaration, Python 2 will complain about any bytes in the file
+        # outside the ASCII range. Sadly, this behavior does not extend to
+        # compile() or ast.parse(), which prefer to interpret the bytes as
+        # latin-1. (At least they properly handle explicit coding cookies.) To
+        # preserve this error behavior, we could force ast.parse() to use ASCII
+        # as the encoding by inserting a coding cookie. Unfortunately, that
+        # messes up line numbers. Thus, we have to check ourselves if anything
+        # is outside the ASCII range in the case no encoding is explicitly
+        # declared. For more context, see issue #269. Yay for Python 3 which
+        # gets this right.
+        end1 = source.find("\n")
+        end2 = source.find("\n", end1 + 1)
+        if (
+            not source.startswith(BOM_UTF8)
+            and cookie_re.match(source[0:end1]) is None
+            and cookie_re.match(source[end1 + 1 : end2]) is None
+        ):
+            if hasattr(state, "_indecode"):
+                # encodings imported us again, so don't rewrite.
+                return None, None
+            state._indecode = True
+            try:
+                try:
+                    source.decode("ascii")
+                except UnicodeDecodeError:
+                    # Let it fail in real import.
+                    return None, None
+            finally:
+                del state._indecode
+    try:
+        tree = ast.parse(source)
+    except SyntaxError:
+        # Let this pop up again in the real import.
+        state.trace("failed to parse: %r" % (fn,))
+        return None, None
+    rewrite_asserts(tree, fn, config)
+    try:
+        co = compile(tree, fn.strpath, "exec", dont_inherit=True)
+    except SyntaxError:
+        # It's possible that this error is from some bug in the
+        # assertion rewriting, but I don't know of a fast way to tell.
+        state.trace("failed to compile: %r" % (fn,))
+        return None, None
+    return stat, co
+
+
+def _read_pyc(source, pyc, trace=lambda x: None):
+    """Possibly read a pytest pyc containing rewritten code.
+
+    Return rewritten code if successful or None if not.
+    """
+    try:
+        fp = open(pyc, "rb")
+    except IOError:
+        return None
+    with fp:
+        try:
+            mtime = int(source.mtime())
+            size = source.size()
+            data = fp.read(12)
+        except EnvironmentError as e:
+            trace("_read_pyc(%s): EnvironmentError %s" % (source, e))
+            return None
+        # Check for invalid or out of date pyc file.
+        if (
+            len(data) != 12
+            or data[:4] != imp.get_magic()
+            or struct.unpack("<ll", data[4:]) != (mtime, size)
+        ):
+            trace("_read_pyc(%s): invalid or out of date pyc" % source)
+            return None
+        try:
+            co = marshal.load(fp)
+        except Exception as e:
+            trace("_read_pyc(%s): marshal.load error %s" % (source, e))
+            return None
+        if not isinstance(co, types.CodeType):
+            trace("_read_pyc(%s): not a code object" % source)
+            return None
+        return co
+
+
+def rewrite_asserts(mod, module_path=None, config=None):
+    """Rewrite the assert statements in mod."""
+    AssertionRewriter(module_path, config).run(mod)
+
+
+def _saferepr(obj):
+    """Get a safe repr of an object for assertion error messages.
+
+    The assertion formatting (util.format_explanation()) requires
+    newlines to be escaped since they are a special character for it.
+    Normally assertion.util.format_explanation() does this but for a
+    custom repr it is possible to contain one of the special escape
+    sequences, especially '\n{' and '\n}' are likely to be present in
+    JSON reprs.
+
+    """
+    repr = py.io.saferepr(obj)
+    if isinstance(repr, six.text_type):
+        t = six.text_type
+    else:
+        t = six.binary_type
+    return repr.replace(t("\n"), t("\\n"))
+
+
+from _pytest.assertion.util import format_explanation as _format_explanation  # noqa
+
+
+def _format_assertmsg(obj):
+    """Format the custom assertion message given.
+
+    For strings this simply replaces newlines with '\n~' so that
+    util.format_explanation() will preserve them instead of escaping
+    newlines.  For other objects py.io.saferepr() is used first.
+
+    """
+    # reprlib appears to have a bug which means that if a string
+    # contains a newline it gets escaped, however if an object has a
+    # .__repr__() which contains newlines it does not get escaped.
+    # However in either case we want to preserve the newline.
+    if isinstance(obj, six.text_type) or isinstance(obj, six.binary_type):
+        s = obj
+        is_repr = False
+    else:
+        s = py.io.saferepr(obj)
+        is_repr = True
+    if isinstance(s, six.text_type):
+        t = six.text_type
+    else:
+        t = six.binary_type
+    s = s.replace(t("\n"), t("\n~")).replace(t("%"), t("%%"))
+    if is_repr:
+        s = s.replace(t("\\n"), t("\n~"))
+    return s
+
+
+def _should_repr_global_name(obj):
+    return not hasattr(obj, "__name__") and not callable(obj)
+
+
+def _format_boolop(explanations, is_or):
+    explanation = "(" + (is_or and " or " or " and ").join(explanations) + ")"
+    if isinstance(explanation, six.text_type):
+        t = six.text_type
+    else:
+        t = six.binary_type
+    return explanation.replace(t("%"), t("%%"))
+
+
+def _call_reprcompare(ops, results, expls, each_obj):
+    for i, res, expl in zip(range(len(ops)), results, expls):
+        try:
+            done = not res
+        except Exception:
+            done = True
+        if done:
+            break
+    if util._reprcompare is not None:
+        custom = util._reprcompare(ops[i], each_obj[i], each_obj[i + 1])
+        if custom is not None:
+            return custom
+    return expl
+
+
+unary_map = {ast.Not: "not %s", ast.Invert: "~%s", ast.USub: "-%s", ast.UAdd: "+%s"}
+
+binop_map = {
+    ast.BitOr: "|",
+    ast.BitXor: "^",
+    ast.BitAnd: "&",
+    ast.LShift: "<<",
+    ast.RShift: ">>",
+    ast.Add: "+",
+    ast.Sub: "-",
+    ast.Mult: "*",
+    ast.Div: "/",
+    ast.FloorDiv: "//",
+    ast.Mod: "%%",  # escaped for string formatting
+    ast.Eq: "==",
+    ast.NotEq: "!=",
+    ast.Lt: "<",
+    ast.LtE: "<=",
+    ast.Gt: ">",
+    ast.GtE: ">=",
+    ast.Pow: "**",
+    ast.Is: "is",
+    ast.IsNot: "is not",
+    ast.In: "in",
+    ast.NotIn: "not in",
+}
+# Python 3.5+ compatibility
+try:
+    binop_map[ast.MatMult] = "@"
+except AttributeError:
+    pass
+
+# Python 3.4+ compatibility
+if hasattr(ast, "NameConstant"):
+    _NameConstant = ast.NameConstant
+else:
+
+    def _NameConstant(c):
+        return ast.Name(str(c), ast.Load())
+
+
+def set_location(node, lineno, col_offset):
+    """Set node location information recursively."""
+
+    def _fix(node, lineno, col_offset):
+        if "lineno" in node._attributes:
+            node.lineno = lineno
+        if "col_offset" in node._attributes:
+            node.col_offset = col_offset
+        for child in ast.iter_child_nodes(node):
+            _fix(child, lineno, col_offset)
+
+    _fix(node, lineno, col_offset)
+    return node
+
+
+class AssertionRewriter(ast.NodeVisitor):
+    """Assertion rewriting implementation.
+
+    The main entrypoint is to call .run() with an ast.Module instance,
+    this will then find all the assert statements and rewrite them to
+    provide intermediate values and a detailed assertion error.  See
+    http://pybites.blogspot.be/2011/07/behind-scenes-of-pytests-new-assertion.html
+    for an overview of how this works.
+
+    The entry point here is .run() which will iterate over all the
+    statements in an ast.Module and for each ast.Assert statement it
+    finds call .visit() with it.  Then .visit_Assert() takes over and
+    is responsible for creating new ast statements to replace the
+    original assert statement: it rewrites the test of an assertion
+    to provide intermediate values and replace it with an if statement
+    which raises an assertion error with a detailed explanation in
+    case the expression is false.
+
+    For this .visit_Assert() uses the visitor pattern to visit all the
+    AST nodes of the ast.Assert.test field, each visit call returning
+    an AST node and the corresponding explanation string.  During this
+    state is kept in several instance attributes:
+
+    :statements: All the AST statements which will replace the assert
+       statement.
+
+    :variables: This is populated by .variable() with each variable
+       used by the statements so that they can all be set to None at
+       the end of the statements.
+
+    :variable_counter: Counter to create new unique variables needed
+       by statements.  Variables are created using .variable() and
+       have the form of "@py_assert0".
+
+    :on_failure: The AST statements which will be executed if the
+       assertion test fails.  This is the code which will construct
+       the failure message and raises the AssertionError.
+
+    :explanation_specifiers: A dict filled by .explanation_param()
+       with %-formatting placeholders and their corresponding
+       expressions to use in the building of an assertion message.
+       This is used by .pop_format_context() to build a message.
+
+    :stack: A stack of the explanation_specifiers dicts maintained by
+       .push_format_context() and .pop_format_context() which allows
+       to build another %-formatted string while already building one.
+
+    This state is reset on every new assert statement visited and used
+    by the other visitors.
+
+    """
+
+    def __init__(self, module_path, config):
+        super(AssertionRewriter, self).__init__()
+        self.module_path = module_path
+        self.config = config
+
+    def run(self, mod):
+        """Find all assert statements in *mod* and rewrite them."""
+        if not mod.body:
+            # Nothing to do.
+            return
+        # Insert some special imports at the top of the module but after any
+        # docstrings and __future__ imports.
+        aliases = [
+            ast.alias(py.builtin.builtins.__name__, "@py_builtins"),
+            ast.alias("_pytest.assertion.rewrite", "@pytest_ar"),
+        ]
+        doc = getattr(mod, "docstring", None)
+        expect_docstring = doc is None
+        if doc is not None and self.is_rewrite_disabled(doc):
+            return
+        pos = 0
+        lineno = 1
+        for item in mod.body:
+            if (
+                expect_docstring
+                and isinstance(item, ast.Expr)
+                and isinstance(item.value, ast.Str)
+            ):
+                doc = item.value.s
+                if self.is_rewrite_disabled(doc):
+                    return
+                expect_docstring = False
+            elif (
+                not isinstance(item, ast.ImportFrom)
+                or item.level > 0
+                or item.module != "__future__"
+            ):
+                lineno = item.lineno
+                break
+            pos += 1
+        else:
+            lineno = item.lineno
+        imports = [
+            ast.Import([alias], lineno=lineno, col_offset=0) for alias in aliases
+        ]
+        mod.body[pos:pos] = imports
+        # Collect asserts.
+        nodes = [mod]
+        while nodes:
+            node = nodes.pop()
+            for name, field in ast.iter_fields(node):
+                if isinstance(field, list):
+                    new = []
+                    for i, child in enumerate(field):
+                        if isinstance(child, ast.Assert):
+                            # Transform assert.
+                            new.extend(self.visit(child))
+                        else:
+                            new.append(child)
+                            if isinstance(child, ast.AST):
+                                nodes.append(child)
+                    setattr(node, name, new)
+                elif (
+                    isinstance(field, ast.AST)
+                    and
+                    # Don't recurse into expressions as they can't contain
+                    # asserts.
+                    not isinstance(field, ast.expr)
+                ):
+                    nodes.append(field)
+
+    @staticmethod
+    def is_rewrite_disabled(docstring):
+        return "PYTEST_DONT_REWRITE" in docstring
+
+    def variable(self):
+        """Get a new variable."""
+        # Use a character invalid in python identifiers to avoid clashing.
+        name = "@py_assert" + str(next(self.variable_counter))
+        self.variables.append(name)
+        return name
+
+    def assign(self, expr):
+        """Give *expr* a name."""
+        name = self.variable()
+        self.statements.append(ast.Assign([ast.Name(name, ast.Store())], expr))
+        return ast.Name(name, ast.Load())
+
+    def display(self, expr):
+        """Call py.io.saferepr on the expression."""
+        return self.helper("saferepr", expr)
+
+    def helper(self, name, *args):
+        """Call a helper in this module."""
+        py_name = ast.Name("@pytest_ar", ast.Load())
+        attr = ast.Attribute(py_name, "_" + name, ast.Load())
+        return ast_Call(attr, list(args), [])
+
+    def builtin(self, name):
+        """Return the builtin called *name*."""
+        builtin_name = ast.Name("@py_builtins", ast.Load())
+        return ast.Attribute(builtin_name, name, ast.Load())
+
+    def explanation_param(self, expr):
+        """Return a new named %-formatting placeholder for expr.
+
+        This creates a %-formatting placeholder for expr in the
+        current formatting context, e.g. ``%(py0)s``.  The placeholder
+        and expr are placed in the current format context so that it
+        can be used on the next call to .pop_format_context().
+
+        """
+        specifier = "py" + str(next(self.variable_counter))
+        self.explanation_specifiers[specifier] = expr
+        return "%(" + specifier + ")s"
+
+    def push_format_context(self):
+        """Create a new formatting context.
+
+        The format context is used for when an explanation wants to
+        have a variable value formatted in the assertion message.  In
+        this case the value required can be added using
+        .explanation_param().  Finally .pop_format_context() is used
+        to format a string of %-formatted values as added by
+        .explanation_param().
+
+        """
+        self.explanation_specifiers = {}
+        self.stack.append(self.explanation_specifiers)
+
+    def pop_format_context(self, expl_expr):
+        """Format the %-formatted string with current format context.
+
+        The expl_expr should be an ast.Str instance constructed from
+        the %-placeholders created by .explanation_param().  This will
+        add the required code to format said string to .on_failure and
+        return the ast.Name instance of the formatted string.
+
+        """
+        current = self.stack.pop()
+        if self.stack:
+            self.explanation_specifiers = self.stack[-1]
+        keys = [ast.Str(key) for key in current.keys()]
+        format_dict = ast.Dict(keys, list(current.values()))
+        form = ast.BinOp(expl_expr, ast.Mod(), format_dict)
+        name = "@py_format" + str(next(self.variable_counter))
+        self.on_failure.append(ast.Assign([ast.Name(name, ast.Store())], form))
+        return ast.Name(name, ast.Load())
+
+    def generic_visit(self, node):
+        """Handle expressions we don't have custom code for."""
+        assert isinstance(node, ast.expr)
+        res = self.assign(node)
+        return res, self.explanation_param(self.display(res))
+
+    def visit_Assert(self, assert_):
+        """Return the AST statements to replace the ast.Assert instance.
+
+        This rewrites the test of an assertion to provide
+        intermediate values and replace it with an if statement which
+        raises an assertion error with a detailed explanation in case
+        the expression is false.
+
+        """
+        if isinstance(assert_.test, ast.Tuple) and self.config is not None:
+            fslocation = (self.module_path, assert_.lineno)
+            self.config.warn(
+                "R1",
+                "assertion is always true, perhaps " "remove parentheses?",
+                fslocation=fslocation,
+            )
+        self.statements = []
+        self.variables = []
+        self.variable_counter = itertools.count()
+        self.stack = []
+        self.on_failure = []
+        self.push_format_context()
+        # Rewrite assert into a bunch of statements.
+        top_condition, explanation = self.visit(assert_.test)
+        # Create failure message.
+        body = self.on_failure
+        negation = ast.UnaryOp(ast.Not(), top_condition)
+        self.statements.append(ast.If(negation, body, []))
+        if assert_.msg:
+            assertmsg = self.helper("format_assertmsg", assert_.msg)
+            explanation = "\n>assert " + explanation
+        else:
+            assertmsg = ast.Str("")
+            explanation = "assert " + explanation
+        template = ast.BinOp(assertmsg, ast.Add(), ast.Str(explanation))
+        msg = self.pop_format_context(template)
+        fmt = self.helper("format_explanation", msg)
+        err_name = ast.Name("AssertionError", ast.Load())
+        exc = ast_Call(err_name, [fmt], [])
+        if sys.version_info[0] >= 3:
+            raise_ = ast.Raise(exc, None)
+        else:
+            raise_ = ast.Raise(exc, None, None)
+        body.append(raise_)
+        # Clear temporary variables by setting them to None.
+        if self.variables:
+            variables = [ast.Name(name, ast.Store()) for name in self.variables]
+            clear = ast.Assign(variables, _NameConstant(None))
+            self.statements.append(clear)
+        # Fix line numbers.
+        for stmt in self.statements:
+            set_location(stmt, assert_.lineno, assert_.col_offset)
+        return self.statements
+
+    def visit_Name(self, name):
+        # Display the repr of the name if it's a local variable or
+        # _should_repr_global_name() thinks it's acceptable.
+        locs = ast_Call(self.builtin("locals"), [], [])
+        inlocs = ast.Compare(ast.Str(name.id), [ast.In()], [locs])
+        dorepr = self.helper("should_repr_global_name", name)
+        test = ast.BoolOp(ast.Or(), [inlocs, dorepr])
+        expr = ast.IfExp(test, self.display(name), ast.Str(name.id))
+        return name, self.explanation_param(expr)
+
+    def visit_BoolOp(self, boolop):
+        res_var = self.variable()
+        expl_list = self.assign(ast.List([], ast.Load()))
+        app = ast.Attribute(expl_list, "append", ast.Load())
+        is_or = int(isinstance(boolop.op, ast.Or))
+        body = save = self.statements
+        fail_save = self.on_failure
+        levels = len(boolop.values) - 1
+        self.push_format_context()
+        # Process each operand, short-circuting if needed.
+        for i, v in enumerate(boolop.values):
+            if i:
+                fail_inner = []
+                # cond is set in a prior loop iteration below
+                self.on_failure.append(ast.If(cond, fail_inner, []))  # noqa
+                self.on_failure = fail_inner
+            self.push_format_context()
+            res, expl = self.visit(v)
+            body.append(ast.Assign([ast.Name(res_var, ast.Store())], res))
+            expl_format = self.pop_format_context(ast.Str(expl))
+            call = ast_Call(app, [expl_format], [])
+            self.on_failure.append(ast.Expr(call))
+            if i < levels:
+                cond = res
+                if is_or:
+                    cond = ast.UnaryOp(ast.Not(), cond)
+                inner = []
+                self.statements.append(ast.If(cond, inner, []))
+                self.statements = body = inner
+        self.statements = save
+        self.on_failure = fail_save
+        expl_template = self.helper("format_boolop", expl_list, ast.Num(is_or))
+        expl = self.pop_format_context(expl_template)
+        return ast.Name(res_var, ast.Load()), self.explanation_param(expl)
+
+    def visit_UnaryOp(self, unary):
+        pattern = unary_map[unary.op.__class__]
+        operand_res, operand_expl = self.visit(unary.operand)
+        res = self.assign(ast.UnaryOp(unary.op, operand_res))
+        return res, pattern % (operand_expl,)
+
+    def visit_BinOp(self, binop):
+        symbol = binop_map[binop.op.__class__]
+        left_expr, left_expl = self.visit(binop.left)
+        right_expr, right_expl = self.visit(binop.right)
+        explanation = "(%s %s %s)" % (left_expl, symbol, right_expl)
+        res = self.assign(ast.BinOp(left_expr, binop.op, right_expr))
+        return res, explanation
+
+    def visit_Call_35(self, call):
+        """
+        visit `ast.Call` nodes on Python3.5 and after
+        """
+        new_func, func_expl = self.visit(call.func)
+        arg_expls = []
+        new_args = []
+        new_kwargs = []
+        for arg in call.args:
+            res, expl = self.visit(arg)
+            arg_expls.append(expl)
+            new_args.append(res)
+        for keyword in call.keywords:
+            res, expl = self.visit(keyword.value)
+            new_kwargs.append(ast.keyword(keyword.arg, res))
+            if keyword.arg:
+                arg_expls.append(keyword.arg + "=" + expl)
+            else:  # **args have `arg` keywords with an .arg of None
+                arg_expls.append("**" + expl)
+
+        expl = "%s(%s)" % (func_expl, ", ".join(arg_expls))
+        new_call = ast.Call(new_func, new_args, new_kwargs)
+        res = self.assign(new_call)
+        res_expl = self.explanation_param(self.display(res))
+        outer_expl = "%s\n{%s = %s\n}" % (res_expl, res_expl, expl)
+        return res, outer_expl
+
+    def visit_Starred(self, starred):
+        # From Python 3.5, a Starred node can appear in a function call
+        res, expl = self.visit(starred.value)
+        return starred, "*" + expl
+
+    def visit_Call_legacy(self, call):
+        """
+        visit `ast.Call nodes on 3.4 and below`
+        """
+        new_func, func_expl = self.visit(call.func)
+        arg_expls = []
+        new_args = []
+        new_kwargs = []
+        new_star = new_kwarg = None
+        for arg in call.args:
+            res, expl = self.visit(arg)
+            new_args.append(res)
+            arg_expls.append(expl)
+        for keyword in call.keywords:
+            res, expl = self.visit(keyword.value)
+            new_kwargs.append(ast.keyword(keyword.arg, res))
+            arg_expls.append(keyword.arg + "=" + expl)
+        if call.starargs:
+            new_star, expl = self.visit(call.starargs)
+            arg_expls.append("*" + expl)
+        if call.kwargs:
+            new_kwarg, expl = self.visit(call.kwargs)
+            arg_expls.append("**" + expl)
+        expl = "%s(%s)" % (func_expl, ", ".join(arg_expls))
+        new_call = ast.Call(new_func, new_args, new_kwargs, new_star, new_kwarg)
+        res = self.assign(new_call)
+        res_expl = self.explanation_param(self.display(res))
+        outer_expl = "%s\n{%s = %s\n}" % (res_expl, res_expl, expl)
+        return res, outer_expl
+
+    # ast.Call signature changed on 3.5,
+    # conditionally change  which methods is named
+    # visit_Call depending on Python version
+    if sys.version_info >= (3, 5):
+        visit_Call = visit_Call_35
+    else:
+        visit_Call = visit_Call_legacy
+
+    def visit_Attribute(self, attr):
+        if not isinstance(attr.ctx, ast.Load):
+            return self.generic_visit(attr)
+        value, value_expl = self.visit(attr.value)
+        res = self.assign(ast.Attribute(value, attr.attr, ast.Load()))
+        res_expl = self.explanation_param(self.display(res))
+        pat = "%s\n{%s = %s.%s\n}"
+        expl = pat % (res_expl, res_expl, value_expl, attr.attr)
+        return res, expl
+
+    def visit_Compare(self, comp):
+        self.push_format_context()
+        left_res, left_expl = self.visit(comp.left)
+        if isinstance(comp.left, (ast.Compare, ast.BoolOp)):
+            left_expl = "({})".format(left_expl)
+        res_variables = [self.variable() for i in range(len(comp.ops))]
+        load_names = [ast.Name(v, ast.Load()) for v in res_variables]
+        store_names = [ast.Name(v, ast.Store()) for v in res_variables]
+        it = zip(range(len(comp.ops)), comp.ops, comp.comparators)
+        expls = []
+        syms = []
+        results = [left_res]
+        for i, op, next_operand in it:
+            next_res, next_expl = self.visit(next_operand)
+            if isinstance(next_operand, (ast.Compare, ast.BoolOp)):
+                next_expl = "({})".format(next_expl)
+            results.append(next_res)
+            sym = binop_map[op.__class__]
+            syms.append(ast.Str(sym))
+            expl = "%s %s %s" % (left_expl, sym, next_expl)
+            expls.append(ast.Str(expl))
+            res_expr = ast.Compare(left_res, [op], [next_res])
+            self.statements.append(ast.Assign([store_names[i]], res_expr))
+            left_res, left_expl = next_res, next_expl
+        # Use pytest.assertion.util._reprcompare if that's available.
+        expl_call = self.helper(
+            "call_reprcompare",
+            ast.Tuple(syms, ast.Load()),
+            ast.Tuple(load_names, ast.Load()),
+            ast.Tuple(expls, ast.Load()),
+            ast.Tuple(results, ast.Load()),
+        )
+        if len(comp.ops) > 1:
+            res = ast.BoolOp(ast.And(), load_names)
+        else:
+            res = load_names[0]
+        return res, self.explanation_param(self.pop_format_context(expl_call))

src/_pytest/assertion/truncate.py

@@ -0,0 +1,99 @@
+"""
+Utilities for truncating assertion output.
+
+Current default behaviour is to truncate assertion explanations at
+~8 terminal lines, unless running in "-vv" mode or running on CI.
+"""
+from __future__ import absolute_import, division, print_function
+import os
+
+import six
+
+
+DEFAULT_MAX_LINES = 8
+DEFAULT_MAX_CHARS = 8 * 80
+USAGE_MSG = "use '-vv' to show"
+
+
+def truncate_if_required(explanation, item, max_length=None):
+    """
+    Truncate this assertion explanation if the given test item is eligible.
+    """
+    if _should_truncate_item(item):
+        return _truncate_explanation(explanation)
+    return explanation
+
+
+def _should_truncate_item(item):
+    """
+    Whether or not this test item is eligible for truncation.
+    """
+    verbose = item.config.option.verbose
+    return verbose < 2 and not _running_on_ci()
+
+
+def _running_on_ci():
+    """Check if we're currently running on a CI system."""
+    env_vars = ["CI", "BUILD_NUMBER"]
+    return any(var in os.environ for var in env_vars)
+
+
+def _truncate_explanation(input_lines, max_lines=None, max_chars=None):
+    """
+    Truncate given list of strings that makes up the assertion explanation.
+
+    Truncates to either 8 lines, or 640 characters - whichever the input reaches
+    first. The remaining lines will be replaced by a usage message.
+    """
+
+    if max_lines is None:
+        max_lines = DEFAULT_MAX_LINES
+    if max_chars is None:
+        max_chars = DEFAULT_MAX_CHARS
+
+    # Check if truncation required
+    input_char_count = len("".join(input_lines))
+    if len(input_lines) <= max_lines and input_char_count <= max_chars:
+        return input_lines
+
+    # Truncate first to max_lines, and then truncate to max_chars if max_chars
+    # is exceeded.
+    truncated_explanation = input_lines[:max_lines]
+    truncated_explanation = _truncate_by_char_count(truncated_explanation, max_chars)
+
+    # Add ellipsis to final line
+    truncated_explanation[-1] = truncated_explanation[-1] + "..."
+
+    # Append useful message to explanation
+    truncated_line_count = len(input_lines) - len(truncated_explanation)
+    truncated_line_count += 1  # Account for the part-truncated final line
+    msg = "...Full output truncated"
+    if truncated_line_count == 1:
+        msg += " ({} line hidden)".format(truncated_line_count)
+    else:
+        msg += " ({} lines hidden)".format(truncated_line_count)
+    msg += ", {}".format(USAGE_MSG)
+    truncated_explanation.extend([six.text_type(""), six.text_type(msg)])
+    return truncated_explanation
+
+
+def _truncate_by_char_count(input_lines, max_chars):
+    # Check if truncation required
+    if len("".join(input_lines)) <= max_chars:
+        return input_lines
+
+    # Find point at which input length exceeds total allowed length
+    iterated_char_count = 0
+    for iterated_index, input_line in enumerate(input_lines):
+        if iterated_char_count + len(input_line) > max_chars:
+            break
+        iterated_char_count += len(input_line)
+
+    # Create truncated explanation with modified final line
+    truncated_result = input_lines[:iterated_index]
+    final_line = input_lines[iterated_index]
+    if final_line:
+        final_line_truncate_point = max_chars - iterated_char_count
+        final_line = final_line[:final_line_truncate_point]
+    truncated_result.append(final_line)
+    return truncated_result

src/_pytest/assertion/util.py

@@ -0,0 +1,338 @@
+"""Utilities for assertion debugging"""
+from __future__ import absolute_import, division, print_function
+import pprint
+
+import _pytest._code
+import py
+import six
+from ..compat import Sequence
+
+u = six.text_type
+
+# The _reprcompare attribute on the util module is used by the new assertion
+# interpretation code and assertion rewriter to detect this plugin was
+# loaded and in turn call the hooks defined here as part of the
+# DebugInterpreter.
+_reprcompare = None
+
+
+# the re-encoding is needed for python2 repr
+# with non-ascii characters (see issue 877 and 1379)
+def ecu(s):
+    try:
+        return u(s, "utf-8", "replace")
+    except TypeError:
+        return s
+
+
+def format_explanation(explanation):
+    """This formats an explanation
+
+    Normally all embedded newlines are escaped, however there are
+    three exceptions: \n{, \n} and \n~.  The first two are intended
+    cover nested explanations, see function and attribute explanations
+    for examples (.visit_Call(), visit_Attribute()).  The last one is
+    for when one explanation needs to span multiple lines, e.g. when
+    displaying diffs.
+    """
+    explanation = ecu(explanation)
+    lines = _split_explanation(explanation)
+    result = _format_lines(lines)
+    return u("\n").join(result)
+
+
+def _split_explanation(explanation):
+    """Return a list of individual lines in the explanation
+
+    This will return a list of lines split on '\n{', '\n}' and '\n~'.
+    Any other newlines will be escaped and appear in the line as the
+    literal '\n' characters.
+    """
+    raw_lines = (explanation or u("")).split("\n")
+    lines = [raw_lines[0]]
+    for values in raw_lines[1:]:
+        if values and values[0] in ["{", "}", "~", ">"]:
+            lines.append(values)
+        else:
+            lines[-1] += "\\n" + values
+    return lines
+
+
+def _format_lines(lines):
+    """Format the individual lines
+
+    This will replace the '{', '}' and '~' characters of our mini
+    formatting language with the proper 'where ...', 'and ...' and ' +
+    ...' text, taking care of indentation along the way.
+
+    Return a list of formatted lines.
+    """
+    result = lines[:1]
+    stack = [0]
+    stackcnt = [0]
+    for line in lines[1:]:
+        if line.startswith("{"):
+            if stackcnt[-1]:
+                s = u("and   ")
+            else:
+                s = u("where ")
+            stack.append(len(result))
+            stackcnt[-1] += 1
+            stackcnt.append(0)
+            result.append(u(" +") + u("  ") * (len(stack) - 1) + s + line[1:])
+        elif line.startswith("}"):
+            stack.pop()
+            stackcnt.pop()
+            result[stack[-1]] += line[1:]
+        else:
+            assert line[0] in ["~", ">"]
+            stack[-1] += 1
+            indent = len(stack) if line.startswith("~") else len(stack) - 1
+            result.append(u("  ") * indent + line[1:])
+    assert len(stack) == 1
+    return result
+
+
+# Provide basestring in python3
+try:
+    basestring = basestring
+except NameError:
+    basestring = str
+
+
+def assertrepr_compare(config, op, left, right):
+    """Return specialised explanations for some operators/operands"""
+    width = 80 - 15 - len(op) - 2  # 15 chars indentation, 1 space around op
+    left_repr = py.io.saferepr(left, maxsize=int(width // 2))
+    right_repr = py.io.saferepr(right, maxsize=width - len(left_repr))
+
+    summary = u("%s %s %s") % (ecu(left_repr), op, ecu(right_repr))
+
+    def issequence(x):
+        return isinstance(x, Sequence) and not isinstance(x, basestring)
+
+    def istext(x):
+        return isinstance(x, basestring)
+
+    def isdict(x):
+        return isinstance(x, dict)
+
+    def isset(x):
+        return isinstance(x, (set, frozenset))
+
+    def isiterable(obj):
+        try:
+            iter(obj)
+            return not istext(obj)
+        except TypeError:
+            return False
+
+    verbose = config.getoption("verbose")
+    explanation = None
+    try:
+        if op == "==":
+            if istext(left) and istext(right):
+                explanation = _diff_text(left, right, verbose)
+            else:
+                if issequence(left) and issequence(right):
+                    explanation = _compare_eq_sequence(left, right, verbose)
+                elif isset(left) and isset(right):
+                    explanation = _compare_eq_set(left, right, verbose)
+                elif isdict(left) and isdict(right):
+                    explanation = _compare_eq_dict(left, right, verbose)
+                if isiterable(left) and isiterable(right):
+                    expl = _compare_eq_iterable(left, right, verbose)
+                    if explanation is not None:
+                        explanation.extend(expl)
+                    else:
+                        explanation = expl
+        elif op == "not in":
+            if istext(left) and istext(right):
+                explanation = _notin_text(left, right, verbose)
+    except Exception:
+        explanation = [
+            u(
+                "(pytest_assertion plugin: representation of details failed.  "
+                "Probably an object has a faulty __repr__.)"
+            ),
+            u(_pytest._code.ExceptionInfo()),
+        ]
+
+    if not explanation:
+        return None
+
+    return [summary] + explanation
+
+
+def _diff_text(left, right, verbose=False):
+    """Return the explanation for the diff between text or bytes
+
+    Unless --verbose is used this will skip leading and trailing
+    characters which are identical to keep the diff minimal.
+
+    If the input are bytes they will be safely converted to text.
+    """
+    from difflib import ndiff
+
+    explanation = []
+
+    def escape_for_readable_diff(binary_text):
+        """
+        Ensures that the internal string is always valid unicode, converting any bytes safely to valid unicode.
+        This is done using repr() which then needs post-processing to fix the encompassing quotes and un-escape
+        newlines and carriage returns (#429).
+        """
+        r = six.text_type(repr(binary_text)[1:-1])
+        r = r.replace(r"\n", "\n")
+        r = r.replace(r"\r", "\r")
+        return r
+
+    if isinstance(left, six.binary_type):
+        left = escape_for_readable_diff(left)
+    if isinstance(right, six.binary_type):
+        right = escape_for_readable_diff(right)
+    if not verbose:
+        i = 0  # just in case left or right has zero length
+        for i in range(min(len(left), len(right))):
+            if left[i] != right[i]:
+                break
+        if i > 42:
+            i -= 10  # Provide some context
+            explanation = [
+                u("Skipping %s identical leading " "characters in diff, use -v to show")
+                % i
+            ]
+            left = left[i:]
+            right = right[i:]
+        if len(left) == len(right):
+            for i in range(len(left)):
+                if left[-i] != right[-i]:
+                    break
+            if i > 42:
+                i -= 10  # Provide some context
+                explanation += [
+                    u(
+                        "Skipping %s identical trailing "
+                        "characters in diff, use -v to show"
+                    )
+                    % i
+                ]
+                left = left[:-i]
+                right = right[:-i]
+    keepends = True
+    if left.isspace() or right.isspace():
+        left = repr(str(left))
+        right = repr(str(right))
+        explanation += [u"Strings contain only whitespace, escaping them using repr()"]
+    explanation += [
+        line.strip("\n")
+        for line in ndiff(left.splitlines(keepends), right.splitlines(keepends))
+    ]
+    return explanation
+
+
+def _compare_eq_iterable(left, right, verbose=False):
+    if not verbose:
+        return [u("Use -v to get the full diff")]
+    # dynamic import to speedup pytest
+    import difflib
+
+    try:
+        left_formatting = pprint.pformat(left).splitlines()
+        right_formatting = pprint.pformat(right).splitlines()
+        explanation = [u("Full diff:")]
+    except Exception:
+        # hack: PrettyPrinter.pformat() in python 2 fails when formatting items that can't be sorted(), ie, calling
+        # sorted() on a list would raise. See issue #718.
+        # As a workaround, the full diff is generated by using the repr() string of each item of each container.
+        left_formatting = sorted(repr(x) for x in left)
+        right_formatting = sorted(repr(x) for x in right)
+        explanation = [u("Full diff (fallback to calling repr on each item):")]
+    explanation.extend(
+        line.strip() for line in difflib.ndiff(left_formatting, right_formatting)
+    )
+    return explanation
+
+
+def _compare_eq_sequence(left, right, verbose=False):
+    explanation = []
+    for i in range(min(len(left), len(right))):
+        if left[i] != right[i]:
+            explanation += [u("At index %s diff: %r != %r") % (i, left[i], right[i])]
+            break
+    if len(left) > len(right):
+        explanation += [
+            u("Left contains more items, first extra item: %s")
+            % py.io.saferepr(left[len(right)])
+        ]
+    elif len(left) < len(right):
+        explanation += [
+            u("Right contains more items, first extra item: %s")
+            % py.io.saferepr(right[len(left)])
+        ]
+    return explanation
+
+
+def _compare_eq_set(left, right, verbose=False):
+    explanation = []
+    diff_left = left - right
+    diff_right = right - left
+    if diff_left:
+        explanation.append(u("Extra items in the left set:"))
+        for item in diff_left:
+            explanation.append(py.io.saferepr(item))
+    if diff_right:
+        explanation.append(u("Extra items in the right set:"))
+        for item in diff_right:
+            explanation.append(py.io.saferepr(item))
+    return explanation
+
+
+def _compare_eq_dict(left, right, verbose=False):
+    explanation = []
+    common = set(left).intersection(set(right))
+    same = {k: left[k] for k in common if left[k] == right[k]}
+    if same and verbose < 2:
+        explanation += [u("Omitting %s identical items, use -vv to show") % len(same)]
+    elif same:
+        explanation += [u("Common items:")]
+        explanation += pprint.pformat(same).splitlines()
+    diff = {k for k in common if left[k] != right[k]}
+    if diff:
+        explanation += [u("Differing items:")]
+        for k in diff:
+            explanation += [
+                py.io.saferepr({k: left[k]}) + " != " + py.io.saferepr({k: right[k]})
+            ]
+    extra_left = set(left) - set(right)
+    if extra_left:
+        explanation.append(u("Left contains more items:"))
+        explanation.extend(
+            pprint.pformat({k: left[k] for k in extra_left}).splitlines()
+        )
+    extra_right = set(right) - set(left)
+    if extra_right:
+        explanation.append(u("Right contains more items:"))
+        explanation.extend(
+            pprint.pformat({k: right[k] for k in extra_right}).splitlines()
+        )
+    return explanation
+
+
+def _notin_text(term, text, verbose=False):
+    index = text.find(term)
+    head = text[:index]
+    tail = text[index + len(term) :]
+    correct_text = head + tail
+    diff = _diff_text(correct_text, text, verbose)
+    newdiff = [u("%s is contained here:") % py.io.saferepr(term, maxsize=42)]
+    for line in diff:
+        if line.startswith(u("Skipping")):
+            continue
+        if line.startswith(u("- ")):
+            continue
+        if line.startswith(u("+ ")):
+            newdiff.append(u("  ") + line[2:])
+        else:
+            newdiff.append(line)
+    return newdiff

src/_pytest/cacheprovider.py

@@ -0,0 +1,351 @@
+"""
+merged implementation of the cache provider
+
+the name cache was not chosen to ensure pluggy automatically
+ignores the external pytest-cache
+"""
+from __future__ import absolute_import, division, print_function
+from collections import OrderedDict
+
+import py
+import six
+import attr
+
+import pytest
+import json
+import shutil
+
+from . import paths
+from .compat import _PY2 as PY2, Path
+
+README_CONTENT = u"""\
+# pytest cache directory #
+
+This directory contains data from the pytest's cache plugin,
+which provides the `--lf` and `--ff` options, as well as the `cache` fixture.
+
+**Do not** commit this to version control.
+
+See [the docs](https://docs.pytest.org/en/latest/cache.html) for more information.
+"""
+
+
+@attr.s
+class Cache(object):
+    _cachedir = attr.ib(repr=False)
+    _warn = attr.ib(repr=False)
+
+    @classmethod
+    def for_config(cls, config):
+        cachedir = cls.cache_dir_from_config(config)
+        if config.getoption("cacheclear") and cachedir.exists():
+            shutil.rmtree(str(cachedir))
+            cachedir.mkdir()
+        return cls(cachedir, config.warn)
+
+    @staticmethod
+    def cache_dir_from_config(config):
+        return paths.resolve_from_str(config.getini("cache_dir"), config.rootdir)
+
+    def warn(self, fmt, **args):
+        self._warn(code="I9", message=fmt.format(**args) if args else fmt)
+
+    def makedir(self, name):
+        """ return a directory path object with the given name.  If the
+        directory does not yet exist, it will be created.  You can use it
+        to manage files likes e. g. store/retrieve database
+        dumps across test sessions.
+
+        :param name: must be a string not containing a ``/`` separator.
+             Make sure the name contains your plugin or application
+             identifiers to prevent clashes with other cache users.
+        """
+        name = Path(name)
+        if len(name.parts) > 1:
+            raise ValueError("name is not allowed to contain path separators")
+        res = self._cachedir.joinpath("d", name)
+        res.mkdir(exist_ok=True, parents=True)
+        return py.path.local(res)
+
+    def _getvaluepath(self, key):
+        return self._cachedir.joinpath("v", Path(key))
+
+    def get(self, key, default):
+        """ return cached value for the given key.  If no value
+        was yet cached or the value cannot be read, the specified
+        default is returned.
+
+        :param key: must be a ``/`` separated value. Usually the first
+             name is the name of your plugin or your application.
+        :param default: must be provided in case of a cache-miss or
+             invalid cache values.
+
+        """
+        path = self._getvaluepath(key)
+        try:
+            with path.open("r") as f:
+                return json.load(f)
+        except (ValueError, IOError, OSError):
+            return default
+
+    def set(self, key, value):
+        """ save value for the given key.
+
+        :param key: must be a ``/`` separated value. Usually the first
+             name is the name of your plugin or your application.
+        :param value: must be of any combination of basic
+               python types, including nested types
+               like e. g. lists of dictionaries.
+        """
+        path = self._getvaluepath(key)
+        try:
+            path.parent.mkdir(exist_ok=True, parents=True)
+        except (IOError, OSError):
+            self.warn("could not create cache path {path}", path=path)
+            return
+        try:
+            f = path.open("wb" if PY2 else "w")
+        except (IOError, OSError):
+            self.warn("cache could not write path {path}", path=path)
+        else:
+            with f:
+                json.dump(value, f, indent=2, sort_keys=True)
+                self._ensure_readme()
+
+    def _ensure_readme(self):
+
+        if self._cachedir.is_dir():
+            readme_path = self._cachedir / "README.md"
+            if not readme_path.is_file():
+                readme_path.write_text(README_CONTENT)
+
+
+class LFPlugin(object):
+    """ Plugin which implements the --lf (run last-failing) option """
+
+    def __init__(self, config):
+        self.config = config
+        active_keys = "lf", "failedfirst"
+        self.active = any(config.getoption(key) for key in active_keys)
+        self.lastfailed = config.cache.get("cache/lastfailed", {})
+        self._previously_failed_count = None
+        self._no_failures_behavior = self.config.getoption("last_failed_no_failures")
+
+    def pytest_report_collectionfinish(self):
+        if self.active:
+            if not self._previously_failed_count:
+                mode = "run {} (no recorded failures)".format(
+                    self._no_failures_behavior
+                )
+            else:
+                noun = "failure" if self._previously_failed_count == 1 else "failures"
+                suffix = " first" if self.config.getoption("failedfirst") else ""
+                mode = "rerun previous {count} {noun}{suffix}".format(
+                    count=self._previously_failed_count, suffix=suffix, noun=noun
+                )
+            return "run-last-failure: %s" % mode
+
+    def pytest_runtest_logreport(self, report):
+        if (report.when == "call" and report.passed) or report.skipped:
+            self.lastfailed.pop(report.nodeid, None)
+        elif report.failed:
+            self.lastfailed[report.nodeid] = True
+
+    def pytest_collectreport(self, report):
+        passed = report.outcome in ("passed", "skipped")
+        if passed:
+            if report.nodeid in self.lastfailed:
+                self.lastfailed.pop(report.nodeid)
+                self.lastfailed.update((item.nodeid, True) for item in report.result)
+        else:
+            self.lastfailed[report.nodeid] = True
+
+    def pytest_collection_modifyitems(self, session, config, items):
+        if self.active:
+            if self.lastfailed:
+                previously_failed = []
+                previously_passed = []
+                for item in items:
+                    if item.nodeid in self.lastfailed:
+                        previously_failed.append(item)
+                    else:
+                        previously_passed.append(item)
+                self._previously_failed_count = len(previously_failed)
+                if not previously_failed:
+                    # running a subset of all tests with recorded failures outside
+                    # of the set of tests currently executing
+                    return
+                if self.config.getoption("lf"):
+                    items[:] = previously_failed
+                    config.hook.pytest_deselected(items=previously_passed)
+                else:
+                    items[:] = previously_failed + previously_passed
+            elif self._no_failures_behavior == "none":
+                config.hook.pytest_deselected(items=items)
+                items[:] = []
+
+    def pytest_sessionfinish(self, session):
+        config = self.config
+        if config.getoption("cacheshow") or hasattr(config, "slaveinput"):
+            return
+
+        saved_lastfailed = config.cache.get("cache/lastfailed", {})
+        if saved_lastfailed != self.lastfailed:
+            config.cache.set("cache/lastfailed", self.lastfailed)
+
+
+class NFPlugin(object):
+    """ Plugin which implements the --nf (run new-first) option """
+
+    def __init__(self, config):
+        self.config = config
+        self.active = config.option.newfirst
+        self.cached_nodeids = config.cache.get("cache/nodeids", [])
+
+    def pytest_collection_modifyitems(self, session, config, items):
+        if self.active:
+            new_items = OrderedDict()
+            other_items = OrderedDict()
+            for item in items:
+                if item.nodeid not in self.cached_nodeids:
+                    new_items[item.nodeid] = item
+                else:
+                    other_items[item.nodeid] = item
+
+            items[:] = self._get_increasing_order(
+                six.itervalues(new_items)
+            ) + self._get_increasing_order(six.itervalues(other_items))
+        self.cached_nodeids = [x.nodeid for x in items if isinstance(x, pytest.Item)]
+
+    def _get_increasing_order(self, items):
+        return sorted(items, key=lambda item: item.fspath.mtime(), reverse=True)
+
+    def pytest_sessionfinish(self, session):
+        config = self.config
+        if config.getoption("cacheshow") or hasattr(config, "slaveinput"):
+            return
+
+        config.cache.set("cache/nodeids", self.cached_nodeids)
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("general")
+    group.addoption(
+        "--lf",
+        "--last-failed",
+        action="store_true",
+        dest="lf",
+        help="rerun only the tests that failed "
+        "at the last run (or all if none failed)",
+    )
+    group.addoption(
+        "--ff",
+        "--failed-first",
+        action="store_true",
+        dest="failedfirst",
+        help="run all tests but run the last failures first.  "
+        "This may re-order tests and thus lead to "
+        "repeated fixture setup/teardown",
+    )
+    group.addoption(
+        "--nf",
+        "--new-first",
+        action="store_true",
+        dest="newfirst",
+        help="run tests from new files first, then the rest of the tests "
+        "sorted by file mtime",
+    )
+    group.addoption(
+        "--cache-show",
+        action="store_true",
+        dest="cacheshow",
+        help="show cache contents, don't perform collection or tests",
+    )
+    group.addoption(
+        "--cache-clear",
+        action="store_true",
+        dest="cacheclear",
+        help="remove all cache contents at start of test run.",
+    )
+    parser.addini("cache_dir", default=".pytest_cache", help="cache directory path.")
+    group.addoption(
+        "--lfnf",
+        "--last-failed-no-failures",
+        action="store",
+        dest="last_failed_no_failures",
+        choices=("all", "none"),
+        default="all",
+        help="change the behavior when no test failed in the last run or no "
+        "information about the last failures was found in the cache",
+    )
+
+
+def pytest_cmdline_main(config):
+    if config.option.cacheshow:
+        from _pytest.main import wrap_session
+
+        return wrap_session(config, cacheshow)
+
+
+@pytest.hookimpl(tryfirst=True)
+def pytest_configure(config):
+    config.cache = Cache.for_config(config)
+    config.pluginmanager.register(LFPlugin(config), "lfplugin")
+    config.pluginmanager.register(NFPlugin(config), "nfplugin")
+
+
+@pytest.fixture
+def cache(request):
+    """
+    Return a cache object that can persist state between testing sessions.
+
+    cache.get(key, default)
+    cache.set(key, value)
+
+    Keys must be a ``/`` separated value, where the first part is usually the
+    name of your plugin or application to avoid clashes with other cache users.
+
+    Values can be any object handled by the json stdlib module.
+    """
+    return request.config.cache
+
+
+def pytest_report_header(config):
+    if config.option.verbose:
+        relpath = config.cache._cachedir.relative_to(config.rootdir)
+        return "cachedir: {}".format(relpath)
+
+
+def cacheshow(config, session):
+    from pprint import pformat
+
+    tw = py.io.TerminalWriter()
+    tw.line("cachedir: " + str(config.cache._cachedir))
+    if not config.cache._cachedir.is_dir():
+        tw.line("cache is empty")
+        return 0
+    dummy = object()
+    basedir = config.cache._cachedir
+    vdir = basedir / "v"
+    tw.sep("-", "cache values")
+    for valpath in sorted(x for x in vdir.rglob("*") if x.is_file()):
+        key = valpath.relative_to(vdir)
+        val = config.cache.get(key, dummy)
+        if val is dummy:
+            tw.line("%s contains unreadable content, " "will be ignored" % key)
+        else:
+            tw.line("%s contains:" % key)
+            for line in pformat(val).splitlines():
+                tw.line("  " + line)
+
+    ddir = basedir / "d"
+    if ddir.is_dir():
+        contents = sorted(ddir.rglob("*"))
+        tw.sep("-", "cache directories")
+        for p in contents:
+            # if p.check(dir=1):
+            #    print("%s/" % p.relto(basedir))
+            if p.is_file():
+                key = p.relative_to(basedir)
+                tw.line("{} is a file of length {:d}".format(key, p.stat().st_size))
+    return 0

src/_pytest/capture.py

@@ -0,0 +1,722 @@
+"""
+per-test stdout/stderr capturing mechanism.
+
+"""
+from __future__ import absolute_import, division, print_function
+
+import collections
+import contextlib
+import sys
+import os
+import io
+from io import UnsupportedOperation
+from tempfile import TemporaryFile
+
+import six
+import pytest
+from _pytest.compat import CaptureIO
+
+
+patchsysdict = {0: "stdin", 1: "stdout", 2: "stderr"}
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("general")
+    group._addoption(
+        "--capture",
+        action="store",
+        default="fd" if hasattr(os, "dup") else "sys",
+        metavar="method",
+        choices=["fd", "sys", "no"],
+        help="per-test capturing method: one of fd|sys|no.",
+    )
+    group._addoption(
+        "-s",
+        action="store_const",
+        const="no",
+        dest="capture",
+        help="shortcut for --capture=no.",
+    )
+
+
+@pytest.hookimpl(hookwrapper=True)
+def pytest_load_initial_conftests(early_config, parser, args):
+    ns = early_config.known_args_namespace
+    if ns.capture == "fd":
+        _py36_windowsconsoleio_workaround(sys.stdout)
+    _colorama_workaround()
+    _readline_workaround()
+    pluginmanager = early_config.pluginmanager
+    capman = CaptureManager(ns.capture)
+    pluginmanager.register(capman, "capturemanager")
+
+    # make sure that capturemanager is properly reset at final shutdown
+    early_config.add_cleanup(capman.stop_global_capturing)
+
+    # make sure logging does not raise exceptions at the end
+    def silence_logging_at_shutdown():
+        if "logging" in sys.modules:
+            sys.modules["logging"].raiseExceptions = False
+
+    early_config.add_cleanup(silence_logging_at_shutdown)
+
+    # finally trigger conftest loading but while capturing (issue93)
+    capman.start_global_capturing()
+    outcome = yield
+    out, err = capman.suspend_global_capture()
+    if outcome.excinfo is not None:
+        sys.stdout.write(out)
+        sys.stderr.write(err)
+
+
+class CaptureManager(object):
+    """
+    Capture plugin, manages that the appropriate capture method is enabled/disabled during collection and each
+    test phase (setup, call, teardown). After each of those points, the captured output is obtained and
+    attached to the collection/runtest report.
+
+    There are two levels of capture:
+    * global: which is enabled by default and can be suppressed by the ``-s`` option. This is always enabled/disabled
+      during collection and each test phase.
+    * fixture: when a test function or one of its fixture depend on the ``capsys`` or ``capfd`` fixtures. In this
+      case special handling is needed to ensure the fixtures take precedence over the global capture.
+    """
+
+    def __init__(self, method):
+        self._method = method
+        self._global_capturing = None
+
+    def _getcapture(self, method):
+        if method == "fd":
+            return MultiCapture(out=True, err=True, Capture=FDCapture)
+        elif method == "sys":
+            return MultiCapture(out=True, err=True, Capture=SysCapture)
+        elif method == "no":
+            return MultiCapture(out=False, err=False, in_=False)
+        else:
+            raise ValueError("unknown capturing method: %r" % method)
+
+    def start_global_capturing(self):
+        assert self._global_capturing is None
+        self._global_capturing = self._getcapture(self._method)
+        self._global_capturing.start_capturing()
+
+    def stop_global_capturing(self):
+        if self._global_capturing is not None:
+            self._global_capturing.pop_outerr_to_orig()
+            self._global_capturing.stop_capturing()
+            self._global_capturing = None
+
+    def resume_global_capture(self):
+        self._global_capturing.resume_capturing()
+
+    def suspend_global_capture(self, item=None, in_=False):
+        if item is not None:
+            self.deactivate_fixture(item)
+        cap = getattr(self, "_global_capturing", None)
+        if cap is not None:
+            try:
+                outerr = cap.readouterr()
+            finally:
+                cap.suspend_capturing(in_=in_)
+            return outerr
+
+    def activate_fixture(self, item):
+        """If the current item is using ``capsys`` or ``capfd``, activate them so they take precedence over
+        the global capture.
+        """
+        fixture = getattr(item, "_capture_fixture", None)
+        if fixture is not None:
+            fixture._start()
+
+    def deactivate_fixture(self, item):
+        """Deactivates the ``capsys`` or ``capfd`` fixture of this item, if any."""
+        fixture = getattr(item, "_capture_fixture", None)
+        if fixture is not None:
+            fixture.close()
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_make_collect_report(self, collector):
+        if isinstance(collector, pytest.File):
+            self.resume_global_capture()
+            outcome = yield
+            out, err = self.suspend_global_capture()
+            rep = outcome.get_result()
+            if out:
+                rep.sections.append(("Captured stdout", out))
+            if err:
+                rep.sections.append(("Captured stderr", err))
+        else:
+            yield
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_setup(self, item):
+        self.resume_global_capture()
+        # no need to activate a capture fixture because they activate themselves during creation; this
+        # only makes sense when a fixture uses a capture fixture, otherwise the capture fixture will
+        # be activated during pytest_runtest_call
+        yield
+        self.suspend_capture_item(item, "setup")
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_call(self, item):
+        self.resume_global_capture()
+        # it is important to activate this fixture during the call phase so it overwrites the "global"
+        # capture
+        self.activate_fixture(item)
+        yield
+        self.suspend_capture_item(item, "call")
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_teardown(self, item):
+        self.resume_global_capture()
+        self.activate_fixture(item)
+        yield
+        self.suspend_capture_item(item, "teardown")
+
+    @pytest.hookimpl(tryfirst=True)
+    def pytest_keyboard_interrupt(self, excinfo):
+        self.stop_global_capturing()
+
+    @pytest.hookimpl(tryfirst=True)
+    def pytest_internalerror(self, excinfo):
+        self.stop_global_capturing()
+
+    def suspend_capture_item(self, item, when, in_=False):
+        out, err = self.suspend_global_capture(item, in_=in_)
+        item.add_report_section(when, "stdout", out)
+        item.add_report_section(when, "stderr", err)
+
+
+capture_fixtures = {"capfd", "capfdbinary", "capsys", "capsysbinary"}
+
+
+def _ensure_only_one_capture_fixture(request, name):
+    fixtures = set(request.fixturenames) & capture_fixtures - {name}
+    if fixtures:
+        fixtures = sorted(fixtures)
+        fixtures = fixtures[0] if len(fixtures) == 1 else fixtures
+        raise request.raiseerror(
+            "cannot use {} and {} at the same time".format(fixtures, name)
+        )
+
+
+@pytest.fixture
+def capsys(request):
+    """Enable capturing of writes to ``sys.stdout`` and ``sys.stderr`` and make
+    captured output available via ``capsys.readouterr()`` method calls
+    which return a ``(out, err)`` namedtuple.  ``out`` and ``err`` will be ``text``
+    objects.
+    """
+    _ensure_only_one_capture_fixture(request, "capsys")
+    with _install_capture_fixture_on_item(request, SysCapture) as fixture:
+        yield fixture
+
+
+@pytest.fixture
+def capsysbinary(request):
+    """Enable capturing of writes to ``sys.stdout`` and ``sys.stderr`` and make
+    captured output available via ``capsys.readouterr()`` method calls
+    which return a ``(out, err)`` tuple.  ``out`` and ``err`` will be ``bytes``
+    objects.
+    """
+    _ensure_only_one_capture_fixture(request, "capsysbinary")
+    # Currently, the implementation uses the python3 specific `.buffer`
+    # property of CaptureIO.
+    if sys.version_info < (3,):
+        raise request.raiseerror("capsysbinary is only supported on python 3")
+    with _install_capture_fixture_on_item(request, SysCaptureBinary) as fixture:
+        yield fixture
+
+
+@pytest.fixture
+def capfd(request):
+    """Enable capturing of writes to file descriptors ``1`` and ``2`` and make
+    captured output available via ``capfd.readouterr()`` method calls
+    which return a ``(out, err)`` tuple.  ``out`` and ``err`` will be ``text``
+    objects.
+    """
+    _ensure_only_one_capture_fixture(request, "capfd")
+    if not hasattr(os, "dup"):
+        pytest.skip(
+            "capfd fixture needs os.dup function which is not available in this system"
+        )
+    with _install_capture_fixture_on_item(request, FDCapture) as fixture:
+        yield fixture
+
+
+@pytest.fixture
+def capfdbinary(request):
+    """Enable capturing of write to file descriptors 1 and 2 and make
+    captured output available via ``capfdbinary.readouterr`` method calls
+    which return a ``(out, err)`` tuple.  ``out`` and ``err`` will be
+    ``bytes`` objects.
+    """
+    _ensure_only_one_capture_fixture(request, "capfdbinary")
+    if not hasattr(os, "dup"):
+        pytest.skip(
+            "capfdbinary fixture needs os.dup function which is not available in this system"
+        )
+    with _install_capture_fixture_on_item(request, FDCaptureBinary) as fixture:
+        yield fixture
+
+
+@contextlib.contextmanager
+def _install_capture_fixture_on_item(request, capture_class):
+    """
+    Context manager which creates a ``CaptureFixture`` instance and "installs" it on
+    the item/node of the given request. Used by ``capsys`` and ``capfd``.
+
+    The CaptureFixture is added as attribute of the item because it needs to accessed
+    by ``CaptureManager`` during its ``pytest_runtest_*`` hooks.
+    """
+    request.node._capture_fixture = fixture = CaptureFixture(capture_class, request)
+    capmanager = request.config.pluginmanager.getplugin("capturemanager")
+    # need to active this fixture right away in case it is being used by another fixture (setup phase)
+    # if this fixture is being used only by a test function (call phase), then we wouldn't need this
+    # activation, but it doesn't hurt
+    capmanager.activate_fixture(request.node)
+    yield fixture
+    fixture.close()
+    del request.node._capture_fixture
+
+
+class CaptureFixture(object):
+    """
+    Object returned by :py:func:`capsys`, :py:func:`capsysbinary`, :py:func:`capfd` and :py:func:`capfdbinary`
+    fixtures.
+    """
+
+    def __init__(self, captureclass, request):
+        self.captureclass = captureclass
+        self.request = request
+
+    def _start(self):
+        self._capture = MultiCapture(
+            out=True, err=True, in_=False, Capture=self.captureclass
+        )
+        self._capture.start_capturing()
+
+    def close(self):
+        cap = self.__dict__.pop("_capture", None)
+        if cap is not None:
+            self._outerr = cap.pop_outerr_to_orig()
+            cap.stop_capturing()
+
+    def readouterr(self):
+        """Read and return the captured output so far, resetting the internal buffer.
+
+        :return: captured content as a namedtuple with  ``out`` and ``err`` string attributes
+        """
+        try:
+            return self._capture.readouterr()
+        except AttributeError:
+            return self._outerr
+
+    @contextlib.contextmanager
+    def disabled(self):
+        """Temporarily disables capture while inside the 'with' block."""
+        self._capture.suspend_capturing()
+        capmanager = self.request.config.pluginmanager.getplugin("capturemanager")
+        capmanager.suspend_global_capture(item=None, in_=False)
+        try:
+            yield
+        finally:
+            capmanager.resume_global_capture()
+            self._capture.resume_capturing()
+
+
+def safe_text_dupfile(f, mode, default_encoding="UTF8"):
+    """ return an open text file object that's a duplicate of f on the
+        FD-level if possible.
+    """
+    encoding = getattr(f, "encoding", None)
+    try:
+        fd = f.fileno()
+    except Exception:
+        if "b" not in getattr(f, "mode", "") and hasattr(f, "encoding"):
+            # we seem to have a text stream, let's just use it
+            return f
+    else:
+        newfd = os.dup(fd)
+        if "b" not in mode:
+            mode += "b"
+        f = os.fdopen(newfd, mode, 0)  # no buffering
+    return EncodedFile(f, encoding or default_encoding)
+
+
+class EncodedFile(object):
+    errors = "strict"  # possibly needed by py3 code (issue555)
+
+    def __init__(self, buffer, encoding):
+        self.buffer = buffer
+        self.encoding = encoding
+
+    def write(self, obj):
+        if isinstance(obj, six.text_type):
+            obj = obj.encode(self.encoding, "replace")
+        self.buffer.write(obj)
+
+    def writelines(self, linelist):
+        data = "".join(linelist)
+        self.write(data)
+
+    @property
+    def name(self):
+        """Ensure that file.name is a string."""
+        return repr(self.buffer)
+
+    def __getattr__(self, name):
+        return getattr(object.__getattribute__(self, "buffer"), name)
+
+
+CaptureResult = collections.namedtuple("CaptureResult", ["out", "err"])
+
+
+class MultiCapture(object):
+    out = err = in_ = None
+
+    def __init__(self, out=True, err=True, in_=True, Capture=None):
+        if in_:
+            self.in_ = Capture(0)
+        if out:
+            self.out = Capture(1)
+        if err:
+            self.err = Capture(2)
+
+    def start_capturing(self):
+        if self.in_:
+            self.in_.start()
+        if self.out:
+            self.out.start()
+        if self.err:
+            self.err.start()
+
+    def pop_outerr_to_orig(self):
+        """ pop current snapshot out/err capture and flush to orig streams. """
+        out, err = self.readouterr()
+        if out:
+            self.out.writeorg(out)
+        if err:
+            self.err.writeorg(err)
+        return out, err
+
+    def suspend_capturing(self, in_=False):
+        if self.out:
+            self.out.suspend()
+        if self.err:
+            self.err.suspend()
+        if in_ and self.in_:
+            self.in_.suspend()
+            self._in_suspended = True
+
+    def resume_capturing(self):
+        if self.out:
+            self.out.resume()
+        if self.err:
+            self.err.resume()
+        if hasattr(self, "_in_suspended"):
+            self.in_.resume()
+            del self._in_suspended
+
+    def stop_capturing(self):
+        """ stop capturing and reset capturing streams """
+        if hasattr(self, "_reset"):
+            raise ValueError("was already stopped")
+        self._reset = True
+        if self.out:
+            self.out.done()
+        if self.err:
+            self.err.done()
+        if self.in_:
+            self.in_.done()
+
+    def readouterr(self):
+        """ return snapshot unicode value of stdout/stderr capturings. """
+        return CaptureResult(
+            self.out.snap() if self.out is not None else "",
+            self.err.snap() if self.err is not None else "",
+        )
+
+
+class NoCapture(object):
+    __init__ = start = done = suspend = resume = lambda *args: None
+
+
+class FDCaptureBinary(object):
+    """Capture IO to/from a given os-level filedescriptor.
+
+    snap() produces `bytes`
+    """
+
+    def __init__(self, targetfd, tmpfile=None):
+        self.targetfd = targetfd
+        try:
+            self.targetfd_save = os.dup(self.targetfd)
+        except OSError:
+            self.start = lambda: None
+            self.done = lambda: None
+        else:
+            if targetfd == 0:
+                assert not tmpfile, "cannot set tmpfile with stdin"
+                tmpfile = open(os.devnull, "r")
+                self.syscapture = SysCapture(targetfd)
+            else:
+                if tmpfile is None:
+                    f = TemporaryFile()
+                    with f:
+                        tmpfile = safe_text_dupfile(f, mode="wb+")
+                if targetfd in patchsysdict:
+                    self.syscapture = SysCapture(targetfd, tmpfile)
+                else:
+                    self.syscapture = NoCapture()
+            self.tmpfile = tmpfile
+            self.tmpfile_fd = tmpfile.fileno()
+
+    def __repr__(self):
+        return "<FDCapture %s oldfd=%s>" % (self.targetfd, self.targetfd_save)
+
+    def start(self):
+        """ Start capturing on targetfd using memorized tmpfile. """
+        try:
+            os.fstat(self.targetfd_save)
+        except (AttributeError, OSError):
+            raise ValueError("saved filedescriptor not valid anymore")
+        os.dup2(self.tmpfile_fd, self.targetfd)
+        self.syscapture.start()
+
+    def snap(self):
+        self.tmpfile.seek(0)
+        res = self.tmpfile.read()
+        self.tmpfile.seek(0)
+        self.tmpfile.truncate()
+        return res
+
+    def done(self):
+        """ stop capturing, restore streams, return original capture file,
+        seeked to position zero. """
+        targetfd_save = self.__dict__.pop("targetfd_save")
+        os.dup2(targetfd_save, self.targetfd)
+        os.close(targetfd_save)
+        self.syscapture.done()
+        _attempt_to_close_capture_file(self.tmpfile)
+
+    def suspend(self):
+        self.syscapture.suspend()
+        os.dup2(self.targetfd_save, self.targetfd)
+
+    def resume(self):
+        self.syscapture.resume()
+        os.dup2(self.tmpfile_fd, self.targetfd)
+
+    def writeorg(self, data):
+        """ write to original file descriptor. """
+        if isinstance(data, six.text_type):
+            data = data.encode("utf8")  # XXX use encoding of original stream
+        os.write(self.targetfd_save, data)
+
+
+class FDCapture(FDCaptureBinary):
+    """Capture IO to/from a given os-level filedescriptor.
+
+    snap() produces text
+    """
+
+    def snap(self):
+        res = FDCaptureBinary.snap(self)
+        enc = getattr(self.tmpfile, "encoding", None)
+        if enc and isinstance(res, bytes):
+            res = six.text_type(res, enc, "replace")
+        return res
+
+
+class SysCapture(object):
+    def __init__(self, fd, tmpfile=None):
+        name = patchsysdict[fd]
+        self._old = getattr(sys, name)
+        self.name = name
+        if tmpfile is None:
+            if name == "stdin":
+                tmpfile = DontReadFromInput()
+            else:
+                tmpfile = CaptureIO()
+        self.tmpfile = tmpfile
+
+    def start(self):
+        setattr(sys, self.name, self.tmpfile)
+
+    def snap(self):
+        res = self.tmpfile.getvalue()
+        self.tmpfile.seek(0)
+        self.tmpfile.truncate()
+        return res
+
+    def done(self):
+        setattr(sys, self.name, self._old)
+        del self._old
+        _attempt_to_close_capture_file(self.tmpfile)
+
+    def suspend(self):
+        setattr(sys, self.name, self._old)
+
+    def resume(self):
+        setattr(sys, self.name, self.tmpfile)
+
+    def writeorg(self, data):
+        self._old.write(data)
+        self._old.flush()
+
+
+class SysCaptureBinary(SysCapture):
+    def snap(self):
+        res = self.tmpfile.buffer.getvalue()
+        self.tmpfile.seek(0)
+        self.tmpfile.truncate()
+        return res
+
+
+class DontReadFromInput(six.Iterator):
+    """Temporary stub class.  Ideally when stdin is accessed, the
+    capturing should be turned off, with possibly all data captured
+    so far sent to the screen.  This should be configurable, though,
+    because in automated test runs it is better to crash than
+    hang indefinitely.
+    """
+
+    encoding = None
+
+    def read(self, *args):
+        raise IOError("reading from stdin while output is captured")
+
+    readline = read
+    readlines = read
+    __next__ = read
+
+    def __iter__(self):
+        return self
+
+    def fileno(self):
+        raise UnsupportedOperation("redirected stdin is pseudofile, " "has no fileno()")
+
+    def isatty(self):
+        return False
+
+    def close(self):
+        pass
+
+    @property
+    def buffer(self):
+        if sys.version_info >= (3, 0):
+            return self
+        else:
+            raise AttributeError("redirected stdin has no attribute buffer")
+
+
+def _colorama_workaround():
+    """
+    Ensure colorama is imported so that it attaches to the correct stdio
+    handles on Windows.
+
+    colorama uses the terminal on import time. So if something does the
+    first import of colorama while I/O capture is active, colorama will
+    fail in various ways.
+    """
+
+    if not sys.platform.startswith("win32"):
+        return
+    try:
+        import colorama  # noqa
+    except ImportError:
+        pass
+
+
+def _readline_workaround():
+    """
+    Ensure readline is imported so that it attaches to the correct stdio
+    handles on Windows.
+
+    Pdb uses readline support where available--when not running from the Python
+    prompt, the readline module is not imported until running the pdb REPL.  If
+    running pytest with the --pdb option this means the readline module is not
+    imported until after I/O capture has been started.
+
+    This is a problem for pyreadline, which is often used to implement readline
+    support on Windows, as it does not attach to the correct handles for stdout
+    and/or stdin if they have been redirected by the FDCapture mechanism.  This
+    workaround ensures that readline is imported before I/O capture is setup so
+    that it can attach to the actual stdin/out for the console.
+
+    See https://github.com/pytest-dev/pytest/pull/1281
+    """
+
+    if not sys.platform.startswith("win32"):
+        return
+    try:
+        import readline  # noqa
+    except ImportError:
+        pass
+
+
+def _py36_windowsconsoleio_workaround(stream):
+    """
+    Python 3.6 implemented unicode console handling for Windows. This works
+    by reading/writing to the raw console handle using
+    ``{Read,Write}ConsoleW``.
+
+    The problem is that we are going to ``dup2`` over the stdio file
+    descriptors when doing ``FDCapture`` and this will ``CloseHandle`` the
+    handles used by Python to write to the console. Though there is still some
+    weirdness and the console handle seems to only be closed randomly and not
+    on the first call to ``CloseHandle``, or maybe it gets reopened with the
+    same handle value when we suspend capturing.
+
+    The workaround in this case will reopen stdio with a different fd which
+    also means a different handle by replicating the logic in
+    "Py_lifecycle.c:initstdio/create_stdio".
+
+    :param stream: in practice ``sys.stdout`` or ``sys.stderr``, but given
+        here as parameter for unittesting purposes.
+
+    See https://github.com/pytest-dev/py/issues/103
+    """
+    if not sys.platform.startswith("win32") or sys.version_info[:2] < (3, 6):
+        return
+
+    # bail out if ``stream`` doesn't seem like a proper ``io`` stream (#2666)
+    if not hasattr(stream, "buffer"):
+        return
+
+    buffered = hasattr(stream.buffer, "raw")
+    raw_stdout = stream.buffer.raw if buffered else stream.buffer
+
+    if not isinstance(raw_stdout, io._WindowsConsoleIO):
+        return
+
+    def _reopen_stdio(f, mode):
+        if not buffered and mode[0] == "w":
+            buffering = 0
+        else:
+            buffering = -1
+
+        return io.TextIOWrapper(
+            open(os.dup(f.fileno()), mode, buffering),
+            f.encoding,
+            f.errors,
+            f.newlines,
+            f.line_buffering,
+        )
+
+    sys.__stdin__ = sys.stdin = _reopen_stdio(sys.stdin, "rb")
+    sys.__stdout__ = sys.stdout = _reopen_stdio(sys.stdout, "wb")
+    sys.__stderr__ = sys.stderr = _reopen_stdio(sys.stderr, "wb")
+
+
+def _attempt_to_close_capture_file(f):
+    """Suppress IOError when closing the temporary file used for capturing streams in py27 (#2370)"""
+    if six.PY2:
+        try:
+            f.close()
+        except IOError:
+            pass
+    else:
+        f.close()

src/_pytest/compat.py

@@ -0,0 +1,367 @@
+"""
+python version compatibility code
+"""
+from __future__ import absolute_import, division, print_function
+
+import codecs
+import functools
+import inspect
+import re
+import sys
+
+import py
+
+import _pytest
+from _pytest.outcomes import TEST_OUTCOME
+from six import text_type
+import six
+
+try:
+    import enum
+except ImportError:  # pragma: no cover
+    # Only available in Python 3.4+ or as a backport
+    enum = None
+
+__all__ = ["Path"]
+
+_PY3 = sys.version_info > (3, 0)
+_PY2 = not _PY3
+
+
+if _PY3:
+    from inspect import signature, Parameter as Parameter
+else:
+    from funcsigs import signature, Parameter as Parameter
+
+NoneType = type(None)
+NOTSET = object()
+
+PY35 = sys.version_info[:2] >= (3, 5)
+PY36 = sys.version_info[:2] >= (3, 6)
+MODULE_NOT_FOUND_ERROR = "ModuleNotFoundError" if PY36 else "ImportError"
+
+if PY36:
+    from pathlib import Path
+else:
+    from pathlib2 import Path
+
+
+if _PY3:
+    from collections.abc import MutableMapping as MappingMixin  # noqa
+    from collections.abc import Mapping, Sequence  # noqa
+else:
+    # those raise DeprecationWarnings in Python >=3.7
+    from collections import MutableMapping as MappingMixin  # noqa
+    from collections import Mapping, Sequence  # noqa
+
+
+def _format_args(func):
+    return str(signature(func))
+
+
+isfunction = inspect.isfunction
+isclass = inspect.isclass
+# used to work around a python2 exception info leak
+exc_clear = getattr(sys, "exc_clear", lambda: None)
+# The type of re.compile objects is not exposed in Python.
+REGEX_TYPE = type(re.compile(""))
+
+
+def is_generator(func):
+    genfunc = inspect.isgeneratorfunction(func)
+    return genfunc and not iscoroutinefunction(func)
+
+
+def iscoroutinefunction(func):
+    """Return True if func is a decorated coroutine function.
+
+    Note: copied and modified from Python 3.5's builtin couroutines.py to avoid import asyncio directly,
+    which in turns also initializes the "logging" module as side-effect (see issue #8).
+    """
+    return getattr(func, "_is_coroutine", False) or (
+        hasattr(inspect, "iscoroutinefunction") and inspect.iscoroutinefunction(func)
+    )
+
+
+def getlocation(function, curdir):
+    fn = py.path.local(inspect.getfile(function))
+    lineno = function.__code__.co_firstlineno
+    if fn.relto(curdir):
+        fn = fn.relto(curdir)
+    return "%s:%d" % (fn, lineno + 1)
+
+
+def num_mock_patch_args(function):
+    """ return number of arguments used up by mock arguments (if any) """
+    patchings = getattr(function, "patchings", None)
+    if not patchings:
+        return 0
+    mock_modules = [sys.modules.get("mock"), sys.modules.get("unittest.mock")]
+    if any(mock_modules):
+        sentinels = [m.DEFAULT for m in mock_modules if m is not None]
+        return len(
+            [p for p in patchings if not p.attribute_name and p.new in sentinels]
+        )
+    return len(patchings)
+
+
+def getfuncargnames(function, is_method=False, cls=None):
+    """Returns the names of a function's mandatory arguments.
+
+    This should return the names of all function arguments that:
+        * Aren't bound to an instance or type as in instance or class methods.
+        * Don't have default values.
+        * Aren't bound with functools.partial.
+        * Aren't replaced with mocks.
+
+    The is_method and cls arguments indicate that the function should
+    be treated as a bound method even though it's not unless, only in
+    the case of cls, the function is a static method.
+
+    @RonnyPfannschmidt: This function should be refactored when we
+    revisit fixtures. The fixture mechanism should ask the node for
+    the fixture names, and not try to obtain directly from the
+    function object well after collection has occurred.
+
+    """
+    # The parameters attribute of a Signature object contains an
+    # ordered mapping of parameter names to Parameter instances.  This
+    # creates a tuple of the names of the parameters that don't have
+    # defaults.
+    arg_names = tuple(
+        p.name
+        for p in signature(function).parameters.values()
+        if (
+            p.kind is Parameter.POSITIONAL_OR_KEYWORD
+            or p.kind is Parameter.KEYWORD_ONLY
+        )
+        and p.default is Parameter.empty
+    )
+    # If this function should be treated as a bound method even though
+    # it's passed as an unbound method or function, remove the first
+    # parameter name.
+    if is_method or (
+        cls and not isinstance(cls.__dict__.get(function.__name__, None), staticmethod)
+    ):
+        arg_names = arg_names[1:]
+    # Remove any names that will be replaced with mocks.
+    if hasattr(function, "__wrapped__"):
+        arg_names = arg_names[num_mock_patch_args(function) :]
+    return arg_names
+
+
+def get_default_arg_names(function):
+    # Note: this code intentionally mirrors the code at the beginning of getfuncargnames,
+    # to get the arguments which were excluded from its result because they had default values
+    return tuple(
+        p.name
+        for p in signature(function).parameters.values()
+        if p.kind in (Parameter.POSITIONAL_OR_KEYWORD, Parameter.KEYWORD_ONLY)
+        and p.default is not Parameter.empty
+    )
+
+
+if _PY3:
+    STRING_TYPES = bytes, str
+    UNICODE_TYPES = six.text_type
+
+    if PY35:
+
+        def _bytes_to_ascii(val):
+            return val.decode("ascii", "backslashreplace")
+
+    else:
+
+        def _bytes_to_ascii(val):
+            if val:
+                # source: http://goo.gl/bGsnwC
+                encoded_bytes, _ = codecs.escape_encode(val)
+                return encoded_bytes.decode("ascii")
+            else:
+                # empty bytes crashes codecs.escape_encode (#1087)
+                return ""
+
+    def ascii_escaped(val):
+        """If val is pure ascii, returns it as a str().  Otherwise, escapes
+        bytes objects into a sequence of escaped bytes:
+
+        b'\xc3\xb4\xc5\xd6' -> u'\\xc3\\xb4\\xc5\\xd6'
+
+        and escapes unicode objects into a sequence of escaped unicode
+        ids, e.g.:
+
+        '4\\nV\\U00043efa\\x0eMXWB\\x1e\\u3028\\u15fd\\xcd\\U0007d944'
+
+        note:
+           the obvious "v.decode('unicode-escape')" will return
+           valid utf-8 unicode if it finds them in bytes, but we
+           want to return escaped bytes for any byte, even if they match
+           a utf-8 string.
+
+        """
+        if isinstance(val, bytes):
+            return _bytes_to_ascii(val)
+        else:
+            return val.encode("unicode_escape").decode("ascii")
+
+
+else:
+    STRING_TYPES = six.string_types
+    UNICODE_TYPES = six.text_type
+
+    def ascii_escaped(val):
+        """In py2 bytes and str are the same type, so return if it's a bytes
+        object, return it unchanged if it is a full ascii string,
+        otherwise escape it into its binary form.
+
+        If it's a unicode string, change the unicode characters into
+        unicode escapes.
+
+        """
+        if isinstance(val, bytes):
+            try:
+                return val.encode("ascii")
+            except UnicodeDecodeError:
+                return val.encode("string-escape")
+        else:
+            return val.encode("unicode-escape")
+
+
+def get_real_func(obj):
+    """ gets the real function object of the (possibly) wrapped object by
+    functools.wraps or functools.partial.
+    """
+    start_obj = obj
+    for i in range(100):
+        new_obj = getattr(obj, "__wrapped__", None)
+        if new_obj is None:
+            break
+        obj = new_obj
+    else:
+        raise ValueError(
+            ("could not find real function of {start}" "\nstopped at {current}").format(
+                start=py.io.saferepr(start_obj), current=py.io.saferepr(obj)
+            )
+        )
+    if isinstance(obj, functools.partial):
+        obj = obj.func
+    return obj
+
+
+def getfslineno(obj):
+    # xxx let decorators etc specify a sane ordering
+    obj = get_real_func(obj)
+    if hasattr(obj, "place_as"):
+        obj = obj.place_as
+    fslineno = _pytest._code.getfslineno(obj)
+    assert isinstance(fslineno[1], int), obj
+    return fslineno
+
+
+def getimfunc(func):
+    try:
+        return func.__func__
+    except AttributeError:
+        return func
+
+
+def safe_getattr(object, name, default):
+    """ Like getattr but return default upon any Exception or any OutcomeException.
+
+    Attribute access can potentially fail for 'evil' Python objects.
+    See issue #214.
+    It catches OutcomeException because of #2490 (issue #580), new outcomes are derived from BaseException
+    instead of Exception (for more details check #2707)
+    """
+    try:
+        return getattr(object, name, default)
+    except TEST_OUTCOME:
+        return default
+
+
+def _is_unittest_unexpected_success_a_failure():
+    """Return if the test suite should fail if an @expectedFailure unittest test PASSES.
+
+    From https://docs.python.org/3/library/unittest.html?highlight=unittest#unittest.TestResult.wasSuccessful:
+        Changed in version 3.4: Returns False if there were any
+        unexpectedSuccesses from tests marked with the expectedFailure() decorator.
+    """
+    return sys.version_info >= (3, 4)
+
+
+if _PY3:
+
+    def safe_str(v):
+        """returns v as string"""
+        return str(v)
+
+
+else:
+
+    def safe_str(v):
+        """returns v as string, converting to ascii if necessary"""
+        try:
+            return str(v)
+        except UnicodeError:
+            if not isinstance(v, text_type):
+                v = text_type(v)
+            errors = "replace"
+            return v.encode("utf-8", errors)
+
+
+COLLECT_FAKEMODULE_ATTRIBUTES = (
+    "Collector",
+    "Module",
+    "Generator",
+    "Function",
+    "Instance",
+    "Session",
+    "Item",
+    "Class",
+    "File",
+    "_fillfuncargs",
+)
+
+
+def _setup_collect_fakemodule():
+    from types import ModuleType
+    import pytest
+
+    pytest.collect = ModuleType("pytest.collect")
+    pytest.collect.__all__ = []  # used for setns
+    for attr in COLLECT_FAKEMODULE_ATTRIBUTES:
+        setattr(pytest.collect, attr, getattr(pytest, attr))
+
+
+if _PY2:
+    # Without this the test_dupfile_on_textio will fail, otherwise CaptureIO could directly inherit from StringIO.
+    from py.io import TextIO
+
+    class CaptureIO(TextIO):
+        @property
+        def encoding(self):
+            return getattr(self, "_encoding", "UTF-8")
+
+
+else:
+    import io
+
+    class CaptureIO(io.TextIOWrapper):
+        def __init__(self):
+            super(CaptureIO, self).__init__(
+                io.BytesIO(), encoding="UTF-8", newline="", write_through=True
+            )
+
+        def getvalue(self):
+            return self.buffer.getvalue().decode("UTF-8")
+
+
+class FuncargnamesCompatAttr(object):
+    """ helper class so that Metafunc, Function and FixtureRequest
+    don't need to each define the "funcargnames" compatibility attribute.
+    """
+
+    @property
+    def funcargnames(self):
+        """ alias attribute for ``fixturenames`` for pre-2.3 compatibility"""
+        return self.fixturenames

src/_pytest/config/__init__.py

@@ -0,0 +1,984 @@
+""" command line options, ini-file and conftest.py processing. """
+from __future__ import absolute_import, division, print_function
+import argparse
+import shlex
+import traceback
+import types
+import warnings
+import copy
+import six
+import py
+
+# DON't import pytest here because it causes import cycle troubles
+import sys
+import os
+from _pytest.outcomes import Skipped
+
+import _pytest._code
+import _pytest.hookspec  # the extension point definitions
+import _pytest.assertion
+from pluggy import PluginManager, HookimplMarker, HookspecMarker
+from _pytest.compat import safe_str
+from .exceptions import UsageError, PrintHelp
+from .findpaths import determine_setup, exists
+
+hookimpl = HookimplMarker("pytest")
+hookspec = HookspecMarker("pytest")
+
+# pytest startup
+#
+
+
+class ConftestImportFailure(Exception):
+    def __init__(self, path, excinfo):
+        Exception.__init__(self, path, excinfo)
+        self.path = path
+        self.excinfo = excinfo
+
+    def __str__(self):
+        etype, evalue, etb = self.excinfo
+        formatted = traceback.format_tb(etb)
+        # The level of the tracebacks we want to print is hand crafted :(
+        return repr(evalue) + "\n" + "".join(formatted[2:])
+
+
+def main(args=None, plugins=None):
+    """ return exit code, after performing an in-process test run.
+
+    :arg args: list of command line arguments.
+
+    :arg plugins: list of plugin objects to be auto-registered during
+                  initialization.
+    """
+    try:
+        try:
+            config = _prepareconfig(args, plugins)
+        except ConftestImportFailure as e:
+            tw = py.io.TerminalWriter(sys.stderr)
+            for line in traceback.format_exception(*e.excinfo):
+                tw.line(line.rstrip(), red=True)
+            tw.line("ERROR: could not load %s\n" % (e.path,), red=True)
+            return 4
+        else:
+            try:
+                return config.hook.pytest_cmdline_main(config=config)
+            finally:
+                config._ensure_unconfigure()
+    except UsageError as e:
+        tw = py.io.TerminalWriter(sys.stderr)
+        for msg in e.args:
+            tw.line("ERROR: {}\n".format(msg), red=True)
+        return 4
+
+
+class cmdline(object):  # NOQA compatibility namespace
+    main = staticmethod(main)
+
+
+def filename_arg(path, optname):
+    """ Argparse type validator for filename arguments.
+
+    :path: path of filename
+    :optname: name of the option
+    """
+    if os.path.isdir(path):
+        raise UsageError("{} must be a filename, given: {}".format(optname, path))
+    return path
+
+
+def directory_arg(path, optname):
+    """Argparse type validator for directory arguments.
+
+    :path: path of directory
+    :optname: name of the option
+    """
+    if not os.path.isdir(path):
+        raise UsageError("{} must be a directory, given: {}".format(optname, path))
+    return path
+
+
+default_plugins = (
+    "mark",
+    "main",
+    "terminal",
+    "runner",
+    "python",
+    "fixtures",
+    "debugging",
+    "unittest",
+    "capture",
+    "skipping",
+    "tmpdir",
+    "monkeypatch",
+    "recwarn",
+    "pastebin",
+    "helpconfig",
+    "nose",
+    "assertion",
+    "junitxml",
+    "resultlog",
+    "doctest",
+    "cacheprovider",
+    "freeze_support",
+    "setuponly",
+    "setupplan",
+    "warnings",
+    "logging",
+)
+
+
+builtin_plugins = set(default_plugins)
+builtin_plugins.add("pytester")
+
+
+def get_config():
+    # subsequent calls to main will create a fresh instance
+    pluginmanager = PytestPluginManager()
+    config = Config(pluginmanager)
+    for spec in default_plugins:
+        pluginmanager.import_plugin(spec)
+    return config
+
+
+def get_plugin_manager():
+    """
+    Obtain a new instance of the
+    :py:class:`_pytest.config.PytestPluginManager`, with default plugins
+    already loaded.
+
+    This function can be used by integration with other tools, like hooking
+    into pytest to run tests into an IDE.
+    """
+    return get_config().pluginmanager
+
+
+def _prepareconfig(args=None, plugins=None):
+    warning = None
+    if args is None:
+        args = sys.argv[1:]
+    elif isinstance(args, py.path.local):
+        args = [str(args)]
+    elif not isinstance(args, (tuple, list)):
+        if not isinstance(args, str):
+            raise ValueError("not a string or argument list: %r" % (args,))
+        args = shlex.split(args, posix=sys.platform != "win32")
+        from _pytest import deprecated
+
+        warning = deprecated.MAIN_STR_ARGS
+    config = get_config()
+    pluginmanager = config.pluginmanager
+    try:
+        if plugins:
+            for plugin in plugins:
+                if isinstance(plugin, six.string_types):
+                    pluginmanager.consider_pluginarg(plugin)
+                else:
+                    pluginmanager.register(plugin)
+        if warning:
+            config.warn("C1", warning)
+        return pluginmanager.hook.pytest_cmdline_parse(
+            pluginmanager=pluginmanager, args=args
+        )
+    except BaseException:
+        config._ensure_unconfigure()
+        raise
+
+
+class PytestPluginManager(PluginManager):
+    """
+    Overwrites :py:class:`pluggy.PluginManager <pluggy.PluginManager>` to add pytest-specific
+    functionality:
+
+    * loading plugins from the command line, ``PYTEST_PLUGINS`` env variable and
+      ``pytest_plugins`` global variables found in plugins being loaded;
+    * ``conftest.py`` loading during start-up;
+    """
+
+    def __init__(self):
+        super(PytestPluginManager, self).__init__("pytest")
+        self._conftest_plugins = set()
+
+        # state related to local conftest plugins
+        self._path2confmods = {}
+        self._conftestpath2mod = {}
+        self._confcutdir = None
+        self._noconftest = False
+        self._duplicatepaths = set()
+
+        self.add_hookspecs(_pytest.hookspec)
+        self.register(self)
+        if os.environ.get("PYTEST_DEBUG"):
+            err = sys.stderr
+            encoding = getattr(err, "encoding", "utf8")
+            try:
+                err = py.io.dupfile(err, encoding=encoding)
+            except Exception:
+                pass
+            self.trace.root.setwriter(err.write)
+            self.enable_tracing()
+
+        # Config._consider_importhook will set a real object if required.
+        self.rewrite_hook = _pytest.assertion.DummyRewriteHook()
+        # Used to know when we are importing conftests after the pytest_configure stage
+        self._configured = False
+
+    def addhooks(self, module_or_class):
+        """
+        .. deprecated:: 2.8
+
+        Use :py:meth:`pluggy.PluginManager.add_hookspecs <PluginManager.add_hookspecs>`
+        instead.
+        """
+        warning = dict(
+            code="I2",
+            fslocation=_pytest._code.getfslineno(sys._getframe(1)),
+            nodeid=None,
+            message="use pluginmanager.add_hookspecs instead of "
+            "deprecated addhooks() method.",
+        )
+        self._warn(warning)
+        return self.add_hookspecs(module_or_class)
+
+    def parse_hookimpl_opts(self, plugin, name):
+        # pytest hooks are always prefixed with pytest_
+        # so we avoid accessing possibly non-readable attributes
+        # (see issue #1073)
+        if not name.startswith("pytest_"):
+            return
+        # ignore some historic special names which can not be hooks anyway
+        if name == "pytest_plugins" or name.startswith("pytest_funcarg__"):
+            return
+
+        method = getattr(plugin, name)
+        opts = super(PytestPluginManager, self).parse_hookimpl_opts(plugin, name)
+
+        # collect unmarked hooks as long as they have the `pytest_' prefix
+        if opts is None and name.startswith("pytest_"):
+            opts = {}
+
+        if opts is not None:
+            for name in ("tryfirst", "trylast", "optionalhook", "hookwrapper"):
+                opts.setdefault(name, hasattr(method, name))
+        return opts
+
+    def parse_hookspec_opts(self, module_or_class, name):
+        opts = super(PytestPluginManager, self).parse_hookspec_opts(
+            module_or_class, name
+        )
+        if opts is None:
+            method = getattr(module_or_class, name)
+            if name.startswith("pytest_"):
+                opts = {
+                    "firstresult": hasattr(method, "firstresult"),
+                    "historic": hasattr(method, "historic"),
+                }
+        return opts
+
+    def register(self, plugin, name=None):
+        if name in ["pytest_catchlog", "pytest_capturelog"]:
+            self._warn(
+                "{} plugin has been merged into the core, "
+                "please remove it from your requirements.".format(
+                    name.replace("_", "-")
+                )
+            )
+            return
+        ret = super(PytestPluginManager, self).register(plugin, name)
+        if ret:
+            self.hook.pytest_plugin_registered.call_historic(
+                kwargs=dict(plugin=plugin, manager=self)
+            )
+
+            if isinstance(plugin, types.ModuleType):
+                self.consider_module(plugin)
+        return ret
+
+    def getplugin(self, name):
+        # support deprecated naming because plugins (xdist e.g.) use it
+        return self.get_plugin(name)
+
+    def hasplugin(self, name):
+        """Return True if the plugin with the given name is registered."""
+        return bool(self.get_plugin(name))
+
+    def pytest_configure(self, config):
+        # XXX now that the pluginmanager exposes hookimpl(tryfirst...)
+        # we should remove tryfirst/trylast as markers
+        config.addinivalue_line(
+            "markers",
+            "tryfirst: mark a hook implementation function such that the "
+            "plugin machinery will try to call it first/as early as possible.",
+        )
+        config.addinivalue_line(
+            "markers",
+            "trylast: mark a hook implementation function such that the "
+            "plugin machinery will try to call it last/as late as possible.",
+        )
+        self._configured = True
+
+    def _warn(self, message):
+        kwargs = (
+            message
+            if isinstance(message, dict)
+            else {"code": "I1", "message": message, "fslocation": None, "nodeid": None}
+        )
+        self.hook.pytest_logwarning.call_historic(kwargs=kwargs)
+
+    #
+    # internal API for local conftest plugin handling
+    #
+    def _set_initial_conftests(self, namespace):
+        """ load initial conftest files given a preparsed "namespace".
+            As conftest files may add their own command line options
+            which have arguments ('--my-opt somepath') we might get some
+            false positives.  All builtin and 3rd party plugins will have
+            been loaded, however, so common options will not confuse our logic
+            here.
+        """
+        current = py.path.local()
+        self._confcutdir = (
+            current.join(namespace.confcutdir, abs=True)
+            if namespace.confcutdir
+            else None
+        )
+        self._noconftest = namespace.noconftest
+        testpaths = namespace.file_or_dir
+        foundanchor = False
+        for path in testpaths:
+            path = str(path)
+            # remove node-id syntax
+            i = path.find("::")
+            if i != -1:
+                path = path[:i]
+            anchor = current.join(path, abs=1)
+            if exists(anchor):  # we found some file object
+                self._try_load_conftest(anchor)
+                foundanchor = True
+        if not foundanchor:
+            self._try_load_conftest(current)
+
+    def _try_load_conftest(self, anchor):
+        self._getconftestmodules(anchor)
+        # let's also consider test* subdirs
+        if anchor.check(dir=1):
+            for x in anchor.listdir("test*"):
+                if x.check(dir=1):
+                    self._getconftestmodules(x)
+
+    def _getconftestmodules(self, path):
+        if self._noconftest:
+            return []
+        try:
+            return self._path2confmods[path]
+        except KeyError:
+            if path.isfile():
+                clist = self._getconftestmodules(path.dirpath())
+            else:
+                # XXX these days we may rather want to use config.rootdir
+                # and allow users to opt into looking into the rootdir parent
+                # directories instead of requiring to specify confcutdir
+                clist = []
+                for parent in path.parts():
+                    if self._confcutdir and self._confcutdir.relto(parent):
+                        continue
+                    conftestpath = parent.join("conftest.py")
+                    if conftestpath.isfile():
+                        mod = self._importconftest(conftestpath)
+                        clist.append(mod)
+
+            self._path2confmods[path] = clist
+            return clist
+
+    def _rget_with_confmod(self, name, path):
+        modules = self._getconftestmodules(path)
+        for mod in reversed(modules):
+            try:
+                return mod, getattr(mod, name)
+            except AttributeError:
+                continue
+        raise KeyError(name)
+
+    def _importconftest(self, conftestpath):
+        try:
+            return self._conftestpath2mod[conftestpath]
+        except KeyError:
+            pkgpath = conftestpath.pypkgpath()
+            if pkgpath is None:
+                _ensure_removed_sysmodule(conftestpath.purebasename)
+            try:
+                mod = conftestpath.pyimport()
+                if hasattr(mod, "pytest_plugins") and self._configured:
+                    from _pytest.deprecated import (
+                        PYTEST_PLUGINS_FROM_NON_TOP_LEVEL_CONFTEST
+                    )
+
+                    warnings.warn(PYTEST_PLUGINS_FROM_NON_TOP_LEVEL_CONFTEST)
+            except Exception:
+                raise ConftestImportFailure(conftestpath, sys.exc_info())
+
+            self._conftest_plugins.add(mod)
+            self._conftestpath2mod[conftestpath] = mod
+            dirpath = conftestpath.dirpath()
+            if dirpath in self._path2confmods:
+                for path, mods in self._path2confmods.items():
+                    if path and path.relto(dirpath) or path == dirpath:
+                        assert mod not in mods
+                        mods.append(mod)
+            self.trace("loaded conftestmodule %r" % (mod))
+            self.consider_conftest(mod)
+            return mod
+
+    #
+    # API for bootstrapping plugin loading
+    #
+    #
+
+    def consider_preparse(self, args):
+        for opt1, opt2 in zip(args, args[1:]):
+            if opt1 == "-p":
+                self.consider_pluginarg(opt2)
+
+    def consider_pluginarg(self, arg):
+        if arg.startswith("no:"):
+            name = arg[3:]
+            self.set_blocked(name)
+            if not name.startswith("pytest_"):
+                self.set_blocked("pytest_" + name)
+        else:
+            self.import_plugin(arg)
+
+    def consider_conftest(self, conftestmodule):
+        self.register(conftestmodule, name=conftestmodule.__file__)
+
+    def consider_env(self):
+        self._import_plugin_specs(os.environ.get("PYTEST_PLUGINS"))
+
+    def consider_module(self, mod):
+        self._import_plugin_specs(getattr(mod, "pytest_plugins", []))
+
+    def _import_plugin_specs(self, spec):
+        plugins = _get_plugin_specs_as_list(spec)
+        for import_spec in plugins:
+            self.import_plugin(import_spec)
+
+    def import_plugin(self, modname):
+        # most often modname refers to builtin modules, e.g. "pytester",
+        # "terminal" or "capture".  Those plugins are registered under their
+        # basename for historic purposes but must be imported with the
+        # _pytest prefix.
+        assert isinstance(modname, (six.text_type, str)), (
+            "module name as text required, got %r" % modname
+        )
+        modname = str(modname)
+        if self.is_blocked(modname) or self.get_plugin(modname) is not None:
+            return
+        if modname in builtin_plugins:
+            importspec = "_pytest." + modname
+        else:
+            importspec = modname
+        self.rewrite_hook.mark_rewrite(importspec)
+        try:
+            __import__(importspec)
+        except ImportError as e:
+            new_exc_type = ImportError
+            new_exc_message = 'Error importing plugin "%s": %s' % (
+                modname,
+                safe_str(e.args[0]),
+            )
+            new_exc = new_exc_type(new_exc_message)
+
+            six.reraise(new_exc_type, new_exc, sys.exc_info()[2])
+
+        except Skipped as e:
+            self._warn("skipped plugin %r: %s" % ((modname, e.msg)))
+        else:
+            mod = sys.modules[importspec]
+            self.register(mod, modname)
+
+
+def _get_plugin_specs_as_list(specs):
+    """
+    Parses a list of "plugin specs" and returns a list of plugin names.
+
+    Plugin specs can be given as a list of strings separated by "," or already as a list/tuple in
+    which case it is returned as a list. Specs can also be `None` in which case an
+    empty list is returned.
+    """
+    if specs is not None:
+        if isinstance(specs, str):
+            specs = specs.split(",") if specs else []
+        if not isinstance(specs, (list, tuple)):
+            raise UsageError(
+                "Plugin specs must be a ','-separated string or a "
+                "list/tuple of strings for plugin names. Given: %r" % specs
+            )
+        return list(specs)
+    return []
+
+
+def _ensure_removed_sysmodule(modname):
+    try:
+        del sys.modules[modname]
+    except KeyError:
+        pass
+
+
+class Notset(object):
+    def __repr__(self):
+        return "<NOTSET>"
+
+
+notset = Notset()
+
+
+def _iter_rewritable_modules(package_files):
+    for fn in package_files:
+        is_simple_module = "/" not in fn and fn.endswith(".py")
+        is_package = fn.count("/") == 1 and fn.endswith("__init__.py")
+        if is_simple_module:
+            module_name, _ = os.path.splitext(fn)
+            yield module_name
+        elif is_package:
+            package_name = os.path.dirname(fn)
+            yield package_name
+
+
+class Config(object):
+    """ access to configuration values, pluginmanager and plugin hooks.  """
+
+    def __init__(self, pluginmanager):
+        #: access to command line option as attributes.
+        #: (deprecated), use :py:func:`getoption() <_pytest.config.Config.getoption>` instead
+        self.option = argparse.Namespace()
+        from .argparsing import Parser, FILE_OR_DIR
+
+        _a = FILE_OR_DIR
+        self._parser = Parser(
+            usage="%%(prog)s [options] [%s] [%s] [...]" % (_a, _a),
+            processopt=self._processopt,
+        )
+        #: a pluginmanager instance
+        self.pluginmanager = pluginmanager
+        self.trace = self.pluginmanager.trace.root.get("config")
+        self.hook = self.pluginmanager.hook
+        self._inicache = {}
+        self._override_ini = ()
+        self._opt2dest = {}
+        self._cleanup = []
+        self._warn = self.pluginmanager._warn
+        self.pluginmanager.register(self, "pytestconfig")
+        self._configured = False
+
+        def do_setns(dic):
+            import pytest
+
+            setns(pytest, dic)
+
+        self.hook.pytest_namespace.call_historic(do_setns, {})
+        self.hook.pytest_addoption.call_historic(kwargs=dict(parser=self._parser))
+
+    def add_cleanup(self, func):
+        """ Add a function to be called when the config object gets out of
+        use (usually coninciding with pytest_unconfigure)."""
+        self._cleanup.append(func)
+
+    def _do_configure(self):
+        assert not self._configured
+        self._configured = True
+        self.hook.pytest_configure.call_historic(kwargs=dict(config=self))
+
+    def _ensure_unconfigure(self):
+        if self._configured:
+            self._configured = False
+            self.hook.pytest_unconfigure(config=self)
+            self.hook.pytest_configure._call_history = []
+        while self._cleanup:
+            fin = self._cleanup.pop()
+            fin()
+
+    def warn(self, code, message, fslocation=None, nodeid=None):
+        """ generate a warning for this test session. """
+        self.hook.pytest_logwarning.call_historic(
+            kwargs=dict(
+                code=code, message=message, fslocation=fslocation, nodeid=nodeid
+            )
+        )
+
+    def get_terminal_writer(self):
+        return self.pluginmanager.get_plugin("terminalreporter")._tw
+
+    def pytest_cmdline_parse(self, pluginmanager, args):
+        # REF1 assert self == pluginmanager.config, (self, pluginmanager.config)
+        self.parse(args)
+        return self
+
+    def notify_exception(self, excinfo, option=None):
+        if option and option.fulltrace:
+            style = "long"
+        else:
+            style = "native"
+        excrepr = excinfo.getrepr(
+            funcargs=True, showlocals=getattr(option, "showlocals", False), style=style
+        )
+        res = self.hook.pytest_internalerror(excrepr=excrepr, excinfo=excinfo)
+        if not any(res):
+            for line in str(excrepr).split("\n"):
+                sys.stderr.write("INTERNALERROR> %s\n" % line)
+                sys.stderr.flush()
+
+    def cwd_relative_nodeid(self, nodeid):
+        # nodeid's are relative to the rootpath, compute relative to cwd
+        if self.invocation_dir != self.rootdir:
+            fullpath = self.rootdir.join(nodeid)
+            nodeid = self.invocation_dir.bestrelpath(fullpath)
+        return nodeid
+
+    @classmethod
+    def fromdictargs(cls, option_dict, args):
+        """ constructor useable for subprocesses. """
+        config = get_config()
+        config.option.__dict__.update(option_dict)
+        config.parse(args, addopts=False)
+        for x in config.option.plugins:
+            config.pluginmanager.consider_pluginarg(x)
+        return config
+
+    def _processopt(self, opt):
+        for name in opt._short_opts + opt._long_opts:
+            self._opt2dest[name] = opt.dest
+
+        if hasattr(opt, "default") and opt.dest:
+            if not hasattr(self.option, opt.dest):
+                setattr(self.option, opt.dest, opt.default)
+
+    @hookimpl(trylast=True)
+    def pytest_load_initial_conftests(self, early_config):
+        self.pluginmanager._set_initial_conftests(early_config.known_args_namespace)
+
+    def _initini(self, args):
+        ns, unknown_args = self._parser.parse_known_and_unknown_args(
+            args, namespace=copy.copy(self.option)
+        )
+        r = determine_setup(
+            ns.inifilename,
+            ns.file_or_dir + unknown_args,
+            warnfunc=self.warn,
+            rootdir_cmd_arg=ns.rootdir or None,
+        )
+        self.rootdir, self.inifile, self.inicfg = r
+        self._parser.extra_info["rootdir"] = self.rootdir
+        self._parser.extra_info["inifile"] = self.inifile
+        self.invocation_dir = py.path.local()
+        self._parser.addini("addopts", "extra command line options", "args")
+        self._parser.addini("minversion", "minimally required pytest version")
+        self._override_ini = ns.override_ini or ()
+
+    def _consider_importhook(self, args):
+        """Install the PEP 302 import hook if using assertion rewriting.
+
+        Needs to parse the --assert=<mode> option from the commandline
+        and find all the installed plugins to mark them for rewriting
+        by the importhook.
+        """
+        ns, unknown_args = self._parser.parse_known_and_unknown_args(args)
+        mode = ns.assertmode
+        if mode == "rewrite":
+            try:
+                hook = _pytest.assertion.install_importhook(self)
+            except SystemError:
+                mode = "plain"
+            else:
+                self._mark_plugins_for_rewrite(hook)
+        _warn_about_missing_assertion(mode)
+
+    def _mark_plugins_for_rewrite(self, hook):
+        """
+        Given an importhook, mark for rewrite any top-level
+        modules or packages in the distribution package for
+        all pytest plugins.
+        """
+        import pkg_resources
+
+        self.pluginmanager.rewrite_hook = hook
+
+        # 'RECORD' available for plugins installed normally (pip install)
+        # 'SOURCES.txt' available for plugins installed in dev mode (pip install -e)
+        # for installed plugins 'SOURCES.txt' returns an empty list, and vice-versa
+        # so it shouldn't be an issue
+        metadata_files = "RECORD", "SOURCES.txt"
+
+        package_files = (
+            entry.split(",")[0]
+            for entrypoint in pkg_resources.iter_entry_points("pytest11")
+            for metadata in metadata_files
+            for entry in entrypoint.dist._get_metadata(metadata)
+        )
+
+        for name in _iter_rewritable_modules(package_files):
+            hook.mark_rewrite(name)
+
+    def _preparse(self, args, addopts=True):
+        if addopts:
+            args[:] = shlex.split(os.environ.get("PYTEST_ADDOPTS", "")) + args
+        self._initini(args)
+        if addopts:
+            args[:] = self.getini("addopts") + args
+        self._checkversion()
+        self._consider_importhook(args)
+        self.pluginmanager.consider_preparse(args)
+        self.pluginmanager.load_setuptools_entrypoints("pytest11")
+        self.pluginmanager.consider_env()
+        self.known_args_namespace = ns = self._parser.parse_known_args(
+            args, namespace=copy.copy(self.option)
+        )
+        if self.known_args_namespace.confcutdir is None and self.inifile:
+            confcutdir = py.path.local(self.inifile).dirname
+            self.known_args_namespace.confcutdir = confcutdir
+        try:
+            self.hook.pytest_load_initial_conftests(
+                early_config=self, args=args, parser=self._parser
+            )
+        except ConftestImportFailure:
+            e = sys.exc_info()[1]
+            if ns.help or ns.version:
+                # we don't want to prevent --help/--version to work
+                # so just let is pass and print a warning at the end
+                self._warn("could not load initial conftests (%s)\n" % e.path)
+            else:
+                raise
+
+    def _checkversion(self):
+        import pytest
+
+        minver = self.inicfg.get("minversion", None)
+        if minver:
+            ver = minver.split(".")
+            myver = pytest.__version__.split(".")
+            if myver < ver:
+                raise pytest.UsageError(
+                    "%s:%d: requires pytest-%s, actual pytest-%s'"
+                    % (
+                        self.inicfg.config.path,
+                        self.inicfg.lineof("minversion"),
+                        minver,
+                        pytest.__version__,
+                    )
+                )
+
+    def parse(self, args, addopts=True):
+        # parse given cmdline arguments into this config object.
+        assert not hasattr(
+            self, "args"
+        ), "can only parse cmdline args at most once per Config object"
+        self._origargs = args
+        self.hook.pytest_addhooks.call_historic(
+            kwargs=dict(pluginmanager=self.pluginmanager)
+        )
+        self._preparse(args, addopts=addopts)
+        # XXX deprecated hook:
+        self.hook.pytest_cmdline_preparse(config=self, args=args)
+        self._parser.after_preparse = True
+        try:
+            args = self._parser.parse_setoption(
+                args, self.option, namespace=self.option
+            )
+            if not args:
+                cwd = os.getcwd()
+                if cwd == self.rootdir:
+                    args = self.getini("testpaths")
+                if not args:
+                    args = [cwd]
+            self.args = args
+        except PrintHelp:
+            pass
+
+    def addinivalue_line(self, name, line):
+        """ add a line to an ini-file option. The option must have been
+        declared but might not yet be set in which case the line becomes the
+        the first line in its value. """
+        x = self.getini(name)
+        assert isinstance(x, list)
+        x.append(line)  # modifies the cached list inline
+
+    def getini(self, name):
+        """ return configuration value from an :ref:`ini file <inifiles>`. If the
+        specified name hasn't been registered through a prior
+        :py:func:`parser.addini <_pytest.config.Parser.addini>`
+        call (usually from a plugin), a ValueError is raised. """
+        try:
+            return self._inicache[name]
+        except KeyError:
+            self._inicache[name] = val = self._getini(name)
+            return val
+
+    def _getini(self, name):
+        try:
+            description, type, default = self._parser._inidict[name]
+        except KeyError:
+            raise ValueError("unknown configuration value: %r" % (name,))
+        value = self._get_override_ini_value(name)
+        if value is None:
+            try:
+                value = self.inicfg[name]
+            except KeyError:
+                if default is not None:
+                    return default
+                if type is None:
+                    return ""
+                return []
+        if type == "pathlist":
+            dp = py.path.local(self.inicfg.config.path).dirpath()
+            values = []
+            for relpath in shlex.split(value):
+                values.append(dp.join(relpath, abs=True))
+            return values
+        elif type == "args":
+            return shlex.split(value)
+        elif type == "linelist":
+            return [t for t in map(lambda x: x.strip(), value.split("\n")) if t]
+        elif type == "bool":
+            return bool(_strtobool(value.strip()))
+        else:
+            assert type is None
+            return value
+
+    def _getconftest_pathlist(self, name, path):
+        try:
+            mod, relroots = self.pluginmanager._rget_with_confmod(name, path)
+        except KeyError:
+            return None
+        modpath = py.path.local(mod.__file__).dirpath()
+        values = []
+        for relroot in relroots:
+            if not isinstance(relroot, py.path.local):
+                relroot = relroot.replace("/", py.path.local.sep)
+                relroot = modpath.join(relroot, abs=True)
+            values.append(relroot)
+        return values
+
+    def _get_override_ini_value(self, name):
+        value = None
+        # override_ini is a list of "ini=value" options
+        # always use the last item if multiple values are set for same ini-name,
+        # e.g. -o foo=bar1 -o foo=bar2 will set foo to bar2
+        for ini_config in self._override_ini:
+            try:
+                key, user_ini_value = ini_config.split("=", 1)
+            except ValueError:
+                raise UsageError("-o/--override-ini expects option=value style.")
+            else:
+                if key == name:
+                    value = user_ini_value
+        return value
+
+    def getoption(self, name, default=notset, skip=False):
+        """ return command line option value.
+
+        :arg name: name of the option.  You may also specify
+            the literal ``--OPT`` option instead of the "dest" option name.
+        :arg default: default value if no option of that name exists.
+        :arg skip: if True raise pytest.skip if option does not exists
+            or has a None value.
+        """
+        name = self._opt2dest.get(name, name)
+        try:
+            val = getattr(self.option, name)
+            if val is None and skip:
+                raise AttributeError(name)
+            return val
+        except AttributeError:
+            if default is not notset:
+                return default
+            if skip:
+                import pytest
+
+                pytest.skip("no %r option found" % (name,))
+            raise ValueError("no option named %r" % (name,))
+
+    def getvalue(self, name, path=None):
+        """ (deprecated, use getoption()) """
+        return self.getoption(name)
+
+    def getvalueorskip(self, name, path=None):
+        """ (deprecated, use getoption(skip=True)) """
+        return self.getoption(name, skip=True)
+
+
+def _assertion_supported():
+    try:
+        assert False
+    except AssertionError:
+        return True
+    else:
+        return False
+
+
+def _warn_about_missing_assertion(mode):
+    if not _assertion_supported():
+        if mode == "plain":
+            sys.stderr.write(
+                "WARNING: ASSERTIONS ARE NOT EXECUTED"
+                " and FAILING TESTS WILL PASS.  Are you"
+                " using python -O?"
+            )
+        else:
+            sys.stderr.write(
+                "WARNING: assertions not in test modules or"
+                " plugins will be ignored"
+                " because assert statements are not executed "
+                "by the underlying Python interpreter "
+                "(are you using python -O?)\n"
+            )
+
+
+def setns(obj, dic):
+    import pytest
+
+    for name, value in dic.items():
+        if isinstance(value, dict):
+            mod = getattr(obj, name, None)
+            if mod is None:
+                modname = "pytest.%s" % name
+                mod = types.ModuleType(modname)
+                sys.modules[modname] = mod
+                mod.__all__ = []
+                setattr(obj, name, mod)
+            obj.__all__.append(name)
+            setns(mod, value)
+        else:
+            setattr(obj, name, value)
+            obj.__all__.append(name)
+            # if obj != pytest:
+            #    pytest.__all__.append(name)
+            setattr(pytest, name, value)
+
+
+def create_terminal_writer(config, *args, **kwargs):
+    """Create a TerminalWriter instance configured according to the options
+    in the config object. Every code which requires a TerminalWriter object
+    and has access to a config object should use this function.
+    """
+    tw = py.io.TerminalWriter(*args, **kwargs)
+    if config.option.color == "yes":
+        tw.hasmarkup = True
+    if config.option.color == "no":
+        tw.hasmarkup = False
+    return tw
+
+
+def _strtobool(val):
+    """Convert a string representation of truth to true (1) or false (0).
+
+    True values are 'y', 'yes', 't', 'true', 'on', and '1'; false values
+    are 'n', 'no', 'f', 'false', 'off', and '0'.  Raises ValueError if
+    'val' is anything else.
+
+    .. note:: copied from distutils.util
+    """
+    val = val.lower()
+    if val in ("y", "yes", "t", "true", "on", "1"):
+        return 1
+    elif val in ("n", "no", "f", "false", "off", "0"):
+        return 0
+    else:
+        raise ValueError("invalid truth value %r" % (val,))

src/_pytest/config/argparsing.py

@@ -0,0 +1,392 @@
+import six
+import warnings
+import argparse
+
+FILE_OR_DIR = "file_or_dir"
+
+
+class Parser(object):
+    """ Parser for command line arguments and ini-file values.
+
+    :ivar extra_info: dict of generic param -> value to display in case
+        there's an error processing the command line arguments.
+    """
+
+    def __init__(self, usage=None, processopt=None):
+        self._anonymous = OptionGroup("custom options", parser=self)
+        self._groups = []
+        self._processopt = processopt
+        self._usage = usage
+        self._inidict = {}
+        self._ininames = []
+        self.extra_info = {}
+
+    def processoption(self, option):
+        if self._processopt:
+            if option.dest:
+                self._processopt(option)
+
+    def getgroup(self, name, description="", after=None):
+        """ get (or create) a named option Group.
+
+        :name: name of the option group.
+        :description: long description for --help output.
+        :after: name of other group, used for ordering --help output.
+
+        The returned group object has an ``addoption`` method with the same
+        signature as :py:func:`parser.addoption
+        <_pytest.config.Parser.addoption>` but will be shown in the
+        respective group in the output of ``pytest. --help``.
+        """
+        for group in self._groups:
+            if group.name == name:
+                return group
+        group = OptionGroup(name, description, parser=self)
+        i = 0
+        for i, grp in enumerate(self._groups):
+            if grp.name == after:
+                break
+        self._groups.insert(i + 1, group)
+        return group
+
+    def addoption(self, *opts, **attrs):
+        """ register a command line option.
+
+        :opts: option names, can be short or long options.
+        :attrs: same attributes which the ``add_option()`` function of the
+           `argparse library
+           <http://docs.python.org/2/library/argparse.html>`_
+           accepts.
+
+        After command line parsing options are available on the pytest config
+        object via ``config.option.NAME`` where ``NAME`` is usually set
+        by passing a ``dest`` attribute, for example
+        ``addoption("--long", dest="NAME", ...)``.
+        """
+        self._anonymous.addoption(*opts, **attrs)
+
+    def parse(self, args, namespace=None):
+        from _pytest._argcomplete import try_argcomplete
+
+        self.optparser = self._getparser()
+        try_argcomplete(self.optparser)
+        return self.optparser.parse_args([str(x) for x in args], namespace=namespace)
+
+    def _getparser(self):
+        from _pytest._argcomplete import filescompleter
+
+        optparser = MyOptionParser(self, self.extra_info)
+        groups = self._groups + [self._anonymous]
+        for group in groups:
+            if group.options:
+                desc = group.description or group.name
+                arggroup = optparser.add_argument_group(desc)
+                for option in group.options:
+                    n = option.names()
+                    a = option.attrs()
+                    arggroup.add_argument(*n, **a)
+        # bash like autocompletion for dirs (appending '/')
+        optparser.add_argument(FILE_OR_DIR, nargs="*").completer = filescompleter
+        return optparser
+
+    def parse_setoption(self, args, option, namespace=None):
+        parsedoption = self.parse(args, namespace=namespace)
+        for name, value in parsedoption.__dict__.items():
+            setattr(option, name, value)
+        return getattr(parsedoption, FILE_OR_DIR)
+
+    def parse_known_args(self, args, namespace=None):
+        """parses and returns a namespace object with known arguments at this
+        point.
+        """
+        return self.parse_known_and_unknown_args(args, namespace=namespace)[0]
+
+    def parse_known_and_unknown_args(self, args, namespace=None):
+        """parses and returns a namespace object with known arguments, and
+        the remaining arguments unknown at this point.
+        """
+        optparser = self._getparser()
+        args = [str(x) for x in args]
+        return optparser.parse_known_args(args, namespace=namespace)
+
+    def addini(self, name, help, type=None, default=None):
+        """ register an ini-file option.
+
+        :name: name of the ini-variable
+        :type: type of the variable, can be ``pathlist``, ``args``, ``linelist``
+               or ``bool``.
+        :default: default value if no ini-file option exists but is queried.
+
+        The value of ini-variables can be retrieved via a call to
+        :py:func:`config.getini(name) <_pytest.config.Config.getini>`.
+        """
+        assert type in (None, "pathlist", "args", "linelist", "bool")
+        self._inidict[name] = (help, type, default)
+        self._ininames.append(name)
+
+
+class ArgumentError(Exception):
+    """
+    Raised if an Argument instance is created with invalid or
+    inconsistent arguments.
+    """
+
+    def __init__(self, msg, option):
+        self.msg = msg
+        self.option_id = str(option)
+
+    def __str__(self):
+        if self.option_id:
+            return "option %s: %s" % (self.option_id, self.msg)
+        else:
+            return self.msg
+
+
+class Argument(object):
+    """class that mimics the necessary behaviour of optparse.Option
+
+    its currently a least effort implementation
+    and ignoring choices and integer prefixes
+    https://docs.python.org/3/library/optparse.html#optparse-standard-option-types
+    """
+
+    _typ_map = {"int": int, "string": str, "float": float, "complex": complex}
+
+    def __init__(self, *names, **attrs):
+        """store parms in private vars for use in add_argument"""
+        self._attrs = attrs
+        self._short_opts = []
+        self._long_opts = []
+        self.dest = attrs.get("dest")
+        if "%default" in (attrs.get("help") or ""):
+            warnings.warn(
+                'pytest now uses argparse. "%default" should be'
+                ' changed to "%(default)s" ',
+                DeprecationWarning,
+                stacklevel=3,
+            )
+        try:
+            typ = attrs["type"]
+        except KeyError:
+            pass
+        else:
+            # this might raise a keyerror as well, don't want to catch that
+            if isinstance(typ, six.string_types):
+                if typ == "choice":
+                    warnings.warn(
+                        "type argument to addoption() is a string %r."
+                        " For parsearg this is optional and when supplied"
+                        " should be a type."
+                        " (options: %s)" % (typ, names),
+                        DeprecationWarning,
+                        stacklevel=3,
+                    )
+                    # argparse expects a type here take it from
+                    # the type of the first element
+                    attrs["type"] = type(attrs["choices"][0])
+                else:
+                    warnings.warn(
+                        "type argument to addoption() is a string %r."
+                        " For parsearg this should be a type."
+                        " (options: %s)" % (typ, names),
+                        DeprecationWarning,
+                        stacklevel=3,
+                    )
+                    attrs["type"] = Argument._typ_map[typ]
+                # used in test_parseopt -> test_parse_defaultgetter
+                self.type = attrs["type"]
+            else:
+                self.type = typ
+        try:
+            # attribute existence is tested in Config._processopt
+            self.default = attrs["default"]
+        except KeyError:
+            pass
+        self._set_opt_strings(names)
+        if not self.dest:
+            if self._long_opts:
+                self.dest = self._long_opts[0][2:].replace("-", "_")
+            else:
+                try:
+                    self.dest = self._short_opts[0][1:]
+                except IndexError:
+                    raise ArgumentError("need a long or short option", self)
+
+    def names(self):
+        return self._short_opts + self._long_opts
+
+    def attrs(self):
+        # update any attributes set by processopt
+        attrs = "default dest help".split()
+        if self.dest:
+            attrs.append(self.dest)
+        for attr in attrs:
+            try:
+                self._attrs[attr] = getattr(self, attr)
+            except AttributeError:
+                pass
+        if self._attrs.get("help"):
+            a = self._attrs["help"]
+            a = a.replace("%default", "%(default)s")
+            # a = a.replace('%prog', '%(prog)s')
+            self._attrs["help"] = a
+        return self._attrs
+
+    def _set_opt_strings(self, opts):
+        """directly from optparse
+
+        might not be necessary as this is passed to argparse later on"""
+        for opt in opts:
+            if len(opt) < 2:
+                raise ArgumentError(
+                    "invalid option string %r: "
+                    "must be at least two characters long" % opt,
+                    self,
+                )
+            elif len(opt) == 2:
+                if not (opt[0] == "-" and opt[1] != "-"):
+                    raise ArgumentError(
+                        "invalid short option string %r: "
+                        "must be of the form -x, (x any non-dash char)" % opt,
+                        self,
+                    )
+                self._short_opts.append(opt)
+            else:
+                if not (opt[0:2] == "--" and opt[2] != "-"):
+                    raise ArgumentError(
+                        "invalid long option string %r: "
+                        "must start with --, followed by non-dash" % opt,
+                        self,
+                    )
+                self._long_opts.append(opt)
+
+    def __repr__(self):
+        args = []
+        if self._short_opts:
+            args += ["_short_opts: " + repr(self._short_opts)]
+        if self._long_opts:
+            args += ["_long_opts: " + repr(self._long_opts)]
+        args += ["dest: " + repr(self.dest)]
+        if hasattr(self, "type"):
+            args += ["type: " + repr(self.type)]
+        if hasattr(self, "default"):
+            args += ["default: " + repr(self.default)]
+        return "Argument({})".format(", ".join(args))
+
+
+class OptionGroup(object):
+    def __init__(self, name, description="", parser=None):
+        self.name = name
+        self.description = description
+        self.options = []
+        self.parser = parser
+
+    def addoption(self, *optnames, **attrs):
+        """ add an option to this group.
+
+        if a shortened version of a long option is specified it will
+        be suppressed in the help. addoption('--twowords', '--two-words')
+        results in help showing '--two-words' only, but --twowords gets
+        accepted **and** the automatic destination is in args.twowords
+        """
+        conflict = set(optnames).intersection(
+            name for opt in self.options for name in opt.names()
+        )
+        if conflict:
+            raise ValueError("option names %s already added" % conflict)
+        option = Argument(*optnames, **attrs)
+        self._addoption_instance(option, shortupper=False)
+
+    def _addoption(self, *optnames, **attrs):
+        option = Argument(*optnames, **attrs)
+        self._addoption_instance(option, shortupper=True)
+
+    def _addoption_instance(self, option, shortupper=False):
+        if not shortupper:
+            for opt in option._short_opts:
+                if opt[0] == "-" and opt[1].islower():
+                    raise ValueError("lowercase shortoptions reserved")
+        if self.parser:
+            self.parser.processoption(option)
+        self.options.append(option)
+
+
+class MyOptionParser(argparse.ArgumentParser):
+    def __init__(self, parser, extra_info=None):
+        if not extra_info:
+            extra_info = {}
+        self._parser = parser
+        argparse.ArgumentParser.__init__(
+            self,
+            usage=parser._usage,
+            add_help=False,
+            formatter_class=DropShorterLongHelpFormatter,
+        )
+        # extra_info is a dict of (param -> value) to display if there's
+        # an usage error to provide more contextual information to the user
+        self.extra_info = extra_info
+
+    def parse_args(self, args=None, namespace=None):
+        """allow splitting of positional arguments"""
+        args, argv = self.parse_known_args(args, namespace)
+        if argv:
+            for arg in argv:
+                if arg and arg[0] == "-":
+                    lines = ["unrecognized arguments: %s" % (" ".join(argv))]
+                    for k, v in sorted(self.extra_info.items()):
+                        lines.append("  %s: %s" % (k, v))
+                    self.error("\n".join(lines))
+            getattr(args, FILE_OR_DIR).extend(argv)
+        return args
+
+
+class DropShorterLongHelpFormatter(argparse.HelpFormatter):
+    """shorten help for long options that differ only in extra hyphens
+
+    - collapse **long** options that are the same except for extra hyphens
+    - special action attribute map_long_option allows surpressing additional
+      long options
+    - shortcut if there are only two options and one of them is a short one
+    - cache result on action object as this is called at least 2 times
+    """
+
+    def _format_action_invocation(self, action):
+        orgstr = argparse.HelpFormatter._format_action_invocation(self, action)
+        if orgstr and orgstr[0] != "-":  # only optional arguments
+            return orgstr
+        res = getattr(action, "_formatted_action_invocation", None)
+        if res:
+            return res
+        options = orgstr.split(", ")
+        if len(options) == 2 and (len(options[0]) == 2 or len(options[1]) == 2):
+            # a shortcut for '-h, --help' or '--abc', '-a'
+            action._formatted_action_invocation = orgstr
+            return orgstr
+        return_list = []
+        option_map = getattr(action, "map_long_option", {})
+        if option_map is None:
+            option_map = {}
+        short_long = {}
+        for option in options:
+            if len(option) == 2 or option[2] == " ":
+                continue
+            if not option.startswith("--"):
+                raise ArgumentError(
+                    'long optional argument without "--": [%s]' % (option), self
+                )
+            xxoption = option[2:]
+            if xxoption.split()[0] not in option_map:
+                shortened = xxoption.replace("-", "")
+                if shortened not in short_long or len(short_long[shortened]) < len(
+                    xxoption
+                ):
+                    short_long[shortened] = xxoption
+        # now short_long has been filled out to the longest with dashes
+        # **and** we keep the right option ordering from add_argument
+        for option in options:
+            if len(option) == 2 or option[2] == " ":
+                return_list.append(option)
+            if option[2:] == short_long.get(option.replace("-", "")):
+                return_list.append(option.replace(" ", "=", 1))
+        action._formatted_action_invocation = ", ".join(return_list)
+        return action._formatted_action_invocation

src/_pytest/config/exceptions.py

@@ -0,0 +1,9 @@
+class UsageError(Exception):
+    """ error in pytest usage or invocation"""
+
+
+class PrintHelp(Exception):
+    """Raised when pytest should print it's help to skip the rest of the
+    argument parsing and validation."""
+
+    pass

src/_pytest/config/findpaths.py

@@ -0,0 +1,139 @@
+import py
+import os
+from .exceptions import UsageError
+
+
+def exists(path, ignore=EnvironmentError):
+    try:
+        return path.check()
+    except ignore:
+        return False
+
+
+def getcfg(args, warnfunc=None):
+    """
+    Search the list of arguments for a valid ini-file for pytest,
+    and return a tuple of (rootdir, inifile, cfg-dict).
+
+    note: warnfunc is an optional function used to warn
+        about ini-files that use deprecated features.
+        This parameter should be removed when pytest
+        adopts standard deprecation warnings (#1804).
+    """
+    from _pytest.deprecated import CFG_PYTEST_SECTION
+
+    inibasenames = ["pytest.ini", "tox.ini", "setup.cfg"]
+    args = [x for x in args if not str(x).startswith("-")]
+    if not args:
+        args = [py.path.local()]
+    for arg in args:
+        arg = py.path.local(arg)
+        for base in arg.parts(reverse=True):
+            for inibasename in inibasenames:
+                p = base.join(inibasename)
+                if exists(p):
+                    iniconfig = py.iniconfig.IniConfig(p)
+                    if "pytest" in iniconfig.sections:
+                        if inibasename == "setup.cfg" and warnfunc:
+                            warnfunc(
+                                "C1", CFG_PYTEST_SECTION.format(filename=inibasename)
+                            )
+                        return base, p, iniconfig["pytest"]
+                    if (
+                        inibasename == "setup.cfg"
+                        and "tool:pytest" in iniconfig.sections
+                    ):
+                        return base, p, iniconfig["tool:pytest"]
+                    elif inibasename == "pytest.ini":
+                        # allowed to be empty
+                        return base, p, {}
+    return None, None, None
+
+
+def get_common_ancestor(paths):
+    common_ancestor = None
+    for path in paths:
+        if not path.exists():
+            continue
+        if common_ancestor is None:
+            common_ancestor = path
+        else:
+            if path.relto(common_ancestor) or path == common_ancestor:
+                continue
+            elif common_ancestor.relto(path):
+                common_ancestor = path
+            else:
+                shared = path.common(common_ancestor)
+                if shared is not None:
+                    common_ancestor = shared
+    if common_ancestor is None:
+        common_ancestor = py.path.local()
+    elif common_ancestor.isfile():
+        common_ancestor = common_ancestor.dirpath()
+    return common_ancestor
+
+
+def get_dirs_from_args(args):
+    def is_option(x):
+        return str(x).startswith("-")
+
+    def get_file_part_from_node_id(x):
+        return str(x).split("::")[0]
+
+    def get_dir_from_path(path):
+        if path.isdir():
+            return path
+        return py.path.local(path.dirname)
+
+    # These look like paths but may not exist
+    possible_paths = (
+        py.path.local(get_file_part_from_node_id(arg))
+        for arg in args
+        if not is_option(arg)
+    )
+
+    return [get_dir_from_path(path) for path in possible_paths if path.exists()]
+
+
+def determine_setup(inifile, args, warnfunc=None, rootdir_cmd_arg=None):
+    dirs = get_dirs_from_args(args)
+    if inifile:
+        iniconfig = py.iniconfig.IniConfig(inifile)
+        is_cfg_file = str(inifile).endswith(".cfg")
+        # TODO: [pytest] section in *.cfg files is depricated. Need refactoring.
+        sections = ["tool:pytest", "pytest"] if is_cfg_file else ["pytest"]
+        for section in sections:
+            try:
+                inicfg = iniconfig[section]
+                if is_cfg_file and section == "pytest" and warnfunc:
+                    from _pytest.deprecated import CFG_PYTEST_SECTION
+
+                    warnfunc("C1", CFG_PYTEST_SECTION.format(filename=str(inifile)))
+                break
+            except KeyError:
+                inicfg = None
+        rootdir = get_common_ancestor(dirs)
+    else:
+        ancestor = get_common_ancestor(dirs)
+        rootdir, inifile, inicfg = getcfg([ancestor], warnfunc=warnfunc)
+        if rootdir is None:
+            for rootdir in ancestor.parts(reverse=True):
+                if rootdir.join("setup.py").exists():
+                    break
+            else:
+                rootdir, inifile, inicfg = getcfg(dirs, warnfunc=warnfunc)
+                if rootdir is None:
+                    rootdir = get_common_ancestor([py.path.local(), ancestor])
+                    is_fs_root = os.path.splitdrive(str(rootdir))[1] == "/"
+                    if is_fs_root:
+                        rootdir = ancestor
+    if rootdir_cmd_arg:
+        rootdir_abs_path = py.path.local(os.path.expandvars(rootdir_cmd_arg))
+        if not os.path.isdir(str(rootdir_abs_path)):
+            raise UsageError(
+                "Directory '{}' not found. Check your '--rootdir' option.".format(
+                    rootdir_abs_path
+                )
+            )
+        rootdir = rootdir_abs_path
+    return rootdir, inifile, inicfg or {}

src/_pytest/debugging.py

@@ -0,0 +1,162 @@
+""" interactive debugging with PDB, the Python Debugger. """
+from __future__ import absolute_import, division, print_function
+import pdb
+import sys
+import os
+from doctest import UnexpectedException
+
+try:
+    from builtins import breakpoint  # noqa
+
+    SUPPORTS_BREAKPOINT_BUILTIN = True
+except ImportError:
+    SUPPORTS_BREAKPOINT_BUILTIN = False
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("general")
+    group._addoption(
+        "--pdb",
+        dest="usepdb",
+        action="store_true",
+        help="start the interactive Python debugger on errors or KeyboardInterrupt.",
+    )
+    group._addoption(
+        "--pdbcls",
+        dest="usepdb_cls",
+        metavar="modulename:classname",
+        help="start a custom interactive Python debugger on errors. "
+        "For example: --pdbcls=IPython.terminal.debugger:TerminalPdb",
+    )
+
+
+def pytest_configure(config):
+    if config.getvalue("usepdb_cls"):
+        modname, classname = config.getvalue("usepdb_cls").split(":")
+        __import__(modname)
+        pdb_cls = getattr(sys.modules[modname], classname)
+    else:
+        pdb_cls = pdb.Pdb
+
+    if config.getvalue("usepdb"):
+        config.pluginmanager.register(PdbInvoke(), "pdbinvoke")
+
+    # Use custom Pdb class set_trace instead of default Pdb on breakpoint() call
+    if SUPPORTS_BREAKPOINT_BUILTIN:
+        _environ_pythonbreakpoint = os.environ.get("PYTHONBREAKPOINT", "")
+        if _environ_pythonbreakpoint == "":
+            sys.breakpointhook = pytestPDB.set_trace
+
+    old = (pdb.set_trace, pytestPDB._pluginmanager)
+
+    def fin():
+        pdb.set_trace, pytestPDB._pluginmanager = old
+        pytestPDB._config = None
+        pytestPDB._pdb_cls = pdb.Pdb
+        if SUPPORTS_BREAKPOINT_BUILTIN:
+            sys.breakpointhook = sys.__breakpointhook__
+
+    pdb.set_trace = pytestPDB.set_trace
+    pytestPDB._pluginmanager = config.pluginmanager
+    pytestPDB._config = config
+    pytestPDB._pdb_cls = pdb_cls
+    config._cleanup.append(fin)
+
+
+class pytestPDB(object):
+    """ Pseudo PDB that defers to the real pdb. """
+
+    _pluginmanager = None
+    _config = None
+    _pdb_cls = pdb.Pdb
+
+    @classmethod
+    def set_trace(cls):
+        """ invoke PDB set_trace debugging, dropping any IO capturing. """
+        import _pytest.config
+
+        frame = sys._getframe().f_back
+        if cls._pluginmanager is not None:
+            capman = cls._pluginmanager.getplugin("capturemanager")
+            if capman:
+                capman.suspend_global_capture(in_=True)
+            tw = _pytest.config.create_terminal_writer(cls._config)
+            tw.line()
+            tw.sep(">", "PDB set_trace (IO-capturing turned off)")
+            cls._pluginmanager.hook.pytest_enter_pdb(config=cls._config)
+        cls._pdb_cls().set_trace(frame)
+
+
+class PdbInvoke(object):
+    def pytest_exception_interact(self, node, call, report):
+        capman = node.config.pluginmanager.getplugin("capturemanager")
+        if capman:
+            out, err = capman.suspend_global_capture(in_=True)
+            sys.stdout.write(out)
+            sys.stdout.write(err)
+        _enter_pdb(node, call.excinfo, report)
+
+    def pytest_internalerror(self, excrepr, excinfo):
+        for line in str(excrepr).split("\n"):
+            sys.stderr.write("INTERNALERROR> %s\n" % line)
+            sys.stderr.flush()
+        tb = _postmortem_traceback(excinfo)
+        post_mortem(tb)
+
+
+def _enter_pdb(node, excinfo, rep):
+    # XXX we re-use the TerminalReporter's terminalwriter
+    # because this seems to avoid some encoding related troubles
+    # for not completely clear reasons.
+    tw = node.config.pluginmanager.getplugin("terminalreporter")._tw
+    tw.line()
+
+    showcapture = node.config.option.showcapture
+
+    for sectionname, content in (
+        ("stdout", rep.capstdout),
+        ("stderr", rep.capstderr),
+        ("log", rep.caplog),
+    ):
+        if showcapture in (sectionname, "all") and content:
+            tw.sep(">", "captured " + sectionname)
+            if content[-1:] == "\n":
+                content = content[:-1]
+            tw.line(content)
+
+    tw.sep(">", "traceback")
+    rep.toterminal(tw)
+    tw.sep(">", "entering PDB")
+    tb = _postmortem_traceback(excinfo)
+    post_mortem(tb)
+    rep._pdbshown = True
+    return rep
+
+
+def _postmortem_traceback(excinfo):
+    if isinstance(excinfo.value, UnexpectedException):
+        # A doctest.UnexpectedException is not useful for post_mortem.
+        # Use the underlying exception instead:
+        return excinfo.value.exc_info[2]
+    else:
+        return excinfo._excinfo[2]
+
+
+def _find_last_non_hidden_frame(stack):
+    i = max(0, len(stack) - 1)
+    while i and stack[i][0].f_locals.get("__tracebackhide__", False):
+        i -= 1
+    return i
+
+
+def post_mortem(t):
+    class Pdb(pytestPDB._pdb_cls):
+        def get_stack(self, f, t):
+            stack, i = pdb.Pdb.get_stack(self, f, t)
+            if f is None:
+                i = _find_last_non_hidden_frame(stack)
+            return stack, i
+
+    p = Pdb()
+    p.reset()
+    p.interaction(None, t)

src/_pytest/deprecated.py

@@ -0,0 +1,67 @@
+"""
+This module contains deprecation messages and bits of code used elsewhere in the codebase
+that is planned to be removed in the next pytest release.
+
+Keeping it in a central location makes it easy to track what is deprecated and should
+be removed when the time comes.
+"""
+from __future__ import absolute_import, division, print_function
+
+
+class RemovedInPytest4Warning(DeprecationWarning):
+    """warning class for features removed in pytest 4.0"""
+
+
+MAIN_STR_ARGS = "passing a string to pytest.main() is deprecated, " "pass a list of arguments instead."
+
+YIELD_TESTS = "yield tests are deprecated, and scheduled to be removed in pytest 4.0"
+
+FUNCARG_PREFIX = (
+    '{name}: declaring fixtures using "pytest_funcarg__" prefix is deprecated '
+    "and scheduled to be removed in pytest 4.0.  "
+    "Please remove the prefix and use the @pytest.fixture decorator instead."
+)
+
+CFG_PYTEST_SECTION = (
+    "[pytest] section in {filename} files is deprecated, use [tool:pytest] instead."
+)
+
+GETFUNCARGVALUE = "use of getfuncargvalue is deprecated, use getfixturevalue"
+
+RESULT_LOG = (
+    "--result-log is deprecated and scheduled for removal in pytest 4.0.\n"
+    "See https://docs.pytest.org/en/latest/usage.html#creating-resultlog-format-files for more information."
+)
+
+MARK_INFO_ATTRIBUTE = RemovedInPytest4Warning(
+    "MarkInfo objects are deprecated as they contain merged marks which are hard to deal with correctly.\n"
+    "Please use node.get_closest_marker(name) or node.iter_markers(name).\n"
+    "Docs: https://docs.pytest.org/en/latest/mark.html#updating-code"
+)
+
+MARK_PARAMETERSET_UNPACKING = RemovedInPytest4Warning(
+    "Applying marks directly to parameters is deprecated,"
+    " please use pytest.param(..., marks=...) instead.\n"
+    "For more details, see: https://docs.pytest.org/en/latest/parametrize.html"
+)
+
+RECORD_XML_PROPERTY = (
+    'Fixture renamed from "record_xml_property" to "record_property" as user '
+    "properties are now available to all reporters.\n"
+    '"record_xml_property" is now deprecated.'
+)
+
+COLLECTOR_MAKEITEM = RemovedInPytest4Warning(
+    "pycollector makeitem was removed " "as it is an accidentially leaked internal api"
+)
+
+METAFUNC_ADD_CALL = (
+    "Metafunc.addcall is deprecated and scheduled to be removed in pytest 4.0.\n"
+    "Please use Metafunc.parametrize instead."
+)
+
+PYTEST_PLUGINS_FROM_NON_TOP_LEVEL_CONFTEST = RemovedInPytest4Warning(
+    "Defining pytest_plugins in a non-top-level conftest is deprecated, "
+    "because it affects the entire directory tree in a non-explicit way.\n"
+    "Please move it to the top level conftest file instead."
+)

src/_pytest/doctest.py

@@ -0,0 +1,511 @@
+""" discover and run doctests in modules and test files."""
+from __future__ import absolute_import, division, print_function
+
+import traceback
+import sys
+import platform
+
+import pytest
+from _pytest._code.code import ExceptionInfo, ReprFileLocation, TerminalRepr
+from _pytest.fixtures import FixtureRequest
+
+
+DOCTEST_REPORT_CHOICE_NONE = "none"
+DOCTEST_REPORT_CHOICE_CDIFF = "cdiff"
+DOCTEST_REPORT_CHOICE_NDIFF = "ndiff"
+DOCTEST_REPORT_CHOICE_UDIFF = "udiff"
+DOCTEST_REPORT_CHOICE_ONLY_FIRST_FAILURE = "only_first_failure"
+
+DOCTEST_REPORT_CHOICES = (
+    DOCTEST_REPORT_CHOICE_NONE,
+    DOCTEST_REPORT_CHOICE_CDIFF,
+    DOCTEST_REPORT_CHOICE_NDIFF,
+    DOCTEST_REPORT_CHOICE_UDIFF,
+    DOCTEST_REPORT_CHOICE_ONLY_FIRST_FAILURE,
+)
+
+# Lazy definition of runner class
+RUNNER_CLASS = None
+
+
+def pytest_addoption(parser):
+    parser.addini(
+        "doctest_optionflags",
+        "option flags for doctests",
+        type="args",
+        default=["ELLIPSIS"],
+    )
+    parser.addini(
+        "doctest_encoding", "encoding used for doctest files", default="utf-8"
+    )
+    group = parser.getgroup("collect")
+    group.addoption(
+        "--doctest-modules",
+        action="store_true",
+        default=False,
+        help="run doctests in all .py modules",
+        dest="doctestmodules",
+    )
+    group.addoption(
+        "--doctest-report",
+        type=str.lower,
+        default="udiff",
+        help="choose another output format for diffs on doctest failure",
+        choices=DOCTEST_REPORT_CHOICES,
+        dest="doctestreport",
+    )
+    group.addoption(
+        "--doctest-glob",
+        action="append",
+        default=[],
+        metavar="pat",
+        help="doctests file matching pattern, default: test*.txt",
+        dest="doctestglob",
+    )
+    group.addoption(
+        "--doctest-ignore-import-errors",
+        action="store_true",
+        default=False,
+        help="ignore doctest ImportErrors",
+        dest="doctest_ignore_import_errors",
+    )
+    group.addoption(
+        "--doctest-continue-on-failure",
+        action="store_true",
+        default=False,
+        help="for a given doctest, continue to run after the first failure",
+        dest="doctest_continue_on_failure",
+    )
+
+
+def pytest_collect_file(path, parent):
+    config = parent.config
+    if path.ext == ".py":
+        if config.option.doctestmodules and not _is_setup_py(config, path, parent):
+            return DoctestModule(path, parent)
+    elif _is_doctest(config, path, parent):
+        return DoctestTextfile(path, parent)
+
+
+def _is_setup_py(config, path, parent):
+    if path.basename != "setup.py":
+        return False
+    contents = path.read()
+    return "setuptools" in contents or "distutils" in contents
+
+
+def _is_doctest(config, path, parent):
+    if path.ext in (".txt", ".rst") and parent.session.isinitpath(path):
+        return True
+    globs = config.getoption("doctestglob") or ["test*.txt"]
+    for glob in globs:
+        if path.check(fnmatch=glob):
+            return True
+    return False
+
+
+class ReprFailDoctest(TerminalRepr):
+    def __init__(self, reprlocation_lines):
+        # List of (reprlocation, lines) tuples
+        self.reprlocation_lines = reprlocation_lines
+
+    def toterminal(self, tw):
+        for reprlocation, lines in self.reprlocation_lines:
+            for line in lines:
+                tw.line(line)
+            reprlocation.toterminal(tw)
+
+
+class MultipleDoctestFailures(Exception):
+    def __init__(self, failures):
+        super(MultipleDoctestFailures, self).__init__()
+        self.failures = failures
+
+
+def _init_runner_class():
+    import doctest
+
+    class PytestDoctestRunner(doctest.DebugRunner):
+        """
+        Runner to collect failures.  Note that the out variable in this case is
+        a list instead of a stdout-like object
+        """
+
+        def __init__(
+            self, checker=None, verbose=None, optionflags=0, continue_on_failure=True
+        ):
+            doctest.DebugRunner.__init__(
+                self, checker=checker, verbose=verbose, optionflags=optionflags
+            )
+            self.continue_on_failure = continue_on_failure
+
+        def report_failure(self, out, test, example, got):
+            failure = doctest.DocTestFailure(test, example, got)
+            if self.continue_on_failure:
+                out.append(failure)
+            else:
+                raise failure
+
+        def report_unexpected_exception(self, out, test, example, exc_info):
+            failure = doctest.UnexpectedException(test, example, exc_info)
+            if self.continue_on_failure:
+                out.append(failure)
+            else:
+                raise failure
+
+    return PytestDoctestRunner
+
+
+def _get_runner(checker=None, verbose=None, optionflags=0, continue_on_failure=True):
+    # We need this in order to do a lazy import on doctest
+    global RUNNER_CLASS
+    if RUNNER_CLASS is None:
+        RUNNER_CLASS = _init_runner_class()
+    return RUNNER_CLASS(
+        checker=checker,
+        verbose=verbose,
+        optionflags=optionflags,
+        continue_on_failure=continue_on_failure,
+    )
+
+
+class DoctestItem(pytest.Item):
+    def __init__(self, name, parent, runner=None, dtest=None):
+        super(DoctestItem, self).__init__(name, parent)
+        self.runner = runner
+        self.dtest = dtest
+        self.obj = None
+        self.fixture_request = None
+
+    def setup(self):
+        if self.dtest is not None:
+            self.fixture_request = _setup_fixtures(self)
+            globs = dict(getfixture=self.fixture_request.getfixturevalue)
+            for name, value in self.fixture_request.getfixturevalue(
+                "doctest_namespace"
+            ).items():
+                globs[name] = value
+            self.dtest.globs.update(globs)
+
+    def runtest(self):
+        _check_all_skipped(self.dtest)
+        self._disable_output_capturing_for_darwin()
+        failures = []
+        self.runner.run(self.dtest, out=failures)
+        if failures:
+            raise MultipleDoctestFailures(failures)
+
+    def _disable_output_capturing_for_darwin(self):
+        """
+        Disable output capturing. Otherwise, stdout is lost to doctest (#985)
+        """
+        if platform.system() != "Darwin":
+            return
+        capman = self.config.pluginmanager.getplugin("capturemanager")
+        if capman:
+            out, err = capman.suspend_global_capture(in_=True)
+            sys.stdout.write(out)
+            sys.stderr.write(err)
+
+    def repr_failure(self, excinfo):
+        import doctest
+
+        failures = None
+        if excinfo.errisinstance((doctest.DocTestFailure, doctest.UnexpectedException)):
+            failures = [excinfo.value]
+        elif excinfo.errisinstance(MultipleDoctestFailures):
+            failures = excinfo.value.failures
+
+        if failures is not None:
+            reprlocation_lines = []
+            for failure in failures:
+                example = failure.example
+                test = failure.test
+                filename = test.filename
+                if test.lineno is None:
+                    lineno = None
+                else:
+                    lineno = test.lineno + example.lineno + 1
+                message = type(failure).__name__
+                reprlocation = ReprFileLocation(filename, lineno, message)
+                checker = _get_checker()
+                report_choice = _get_report_choice(
+                    self.config.getoption("doctestreport")
+                )
+                if lineno is not None:
+                    lines = failure.test.docstring.splitlines(False)
+                    # add line numbers to the left of the error message
+                    lines = [
+                        "%03d %s" % (i + test.lineno + 1, x)
+                        for (i, x) in enumerate(lines)
+                    ]
+                    # trim docstring error lines to 10
+                    lines = lines[max(example.lineno - 9, 0) : example.lineno + 1]
+                else:
+                    lines = [
+                        "EXAMPLE LOCATION UNKNOWN, not showing all tests of that example"
+                    ]
+                    indent = ">>>"
+                    for line in example.source.splitlines():
+                        lines.append("??? %s %s" % (indent, line))
+                        indent = "..."
+                if isinstance(failure, doctest.DocTestFailure):
+                    lines += checker.output_difference(
+                        example, failure.got, report_choice
+                    ).split("\n")
+                else:
+                    inner_excinfo = ExceptionInfo(failure.exc_info)
+                    lines += ["UNEXPECTED EXCEPTION: %s" % repr(inner_excinfo.value)]
+                    lines += traceback.format_exception(*failure.exc_info)
+                reprlocation_lines.append((reprlocation, lines))
+            return ReprFailDoctest(reprlocation_lines)
+        else:
+            return super(DoctestItem, self).repr_failure(excinfo)
+
+    def reportinfo(self):
+        return self.fspath, self.dtest.lineno, "[doctest] %s" % self.name
+
+
+def _get_flag_lookup():
+    import doctest
+
+    return dict(
+        DONT_ACCEPT_TRUE_FOR_1=doctest.DONT_ACCEPT_TRUE_FOR_1,
+        DONT_ACCEPT_BLANKLINE=doctest.DONT_ACCEPT_BLANKLINE,
+        NORMALIZE_WHITESPACE=doctest.NORMALIZE_WHITESPACE,
+        ELLIPSIS=doctest.ELLIPSIS,
+        IGNORE_EXCEPTION_DETAIL=doctest.IGNORE_EXCEPTION_DETAIL,
+        COMPARISON_FLAGS=doctest.COMPARISON_FLAGS,
+        ALLOW_UNICODE=_get_allow_unicode_flag(),
+        ALLOW_BYTES=_get_allow_bytes_flag(),
+    )
+
+
+def get_optionflags(parent):
+    optionflags_str = parent.config.getini("doctest_optionflags")
+    flag_lookup_table = _get_flag_lookup()
+    flag_acc = 0
+    for flag in optionflags_str:
+        flag_acc |= flag_lookup_table[flag]
+    return flag_acc
+
+
+def _get_continue_on_failure(config):
+    continue_on_failure = config.getvalue("doctest_continue_on_failure")
+    if continue_on_failure:
+        # We need to turn off this if we use pdb since we should stop at
+        # the first failure
+        if config.getvalue("usepdb"):
+            continue_on_failure = False
+    return continue_on_failure
+
+
+class DoctestTextfile(pytest.Module):
+    obj = None
+
+    def collect(self):
+        import doctest
+
+        # inspired by doctest.testfile; ideally we would use it directly,
+        # but it doesn't support passing a custom checker
+        encoding = self.config.getini("doctest_encoding")
+        text = self.fspath.read_text(encoding)
+        filename = str(self.fspath)
+        name = self.fspath.basename
+        globs = {"__name__": "__main__"}
+
+        optionflags = get_optionflags(self)
+
+        runner = _get_runner(
+            verbose=0,
+            optionflags=optionflags,
+            checker=_get_checker(),
+            continue_on_failure=_get_continue_on_failure(self.config),
+        )
+        _fix_spoof_python2(runner, encoding)
+
+        parser = doctest.DocTestParser()
+        test = parser.get_doctest(text, globs, name, filename, 0)
+        if test.examples:
+            yield DoctestItem(test.name, self, runner, test)
+
+
+def _check_all_skipped(test):
+    """raises pytest.skip() if all examples in the given DocTest have the SKIP
+    option set.
+    """
+    import doctest
+
+    all_skipped = all(x.options.get(doctest.SKIP, False) for x in test.examples)
+    if all_skipped:
+        pytest.skip("all tests skipped by +SKIP option")
+
+
+class DoctestModule(pytest.Module):
+    def collect(self):
+        import doctest
+
+        if self.fspath.basename == "conftest.py":
+            module = self.config.pluginmanager._importconftest(self.fspath)
+        else:
+            try:
+                module = self.fspath.pyimport()
+            except ImportError:
+                if self.config.getvalue("doctest_ignore_import_errors"):
+                    pytest.skip("unable to import module %r" % self.fspath)
+                else:
+                    raise
+        # uses internal doctest module parsing mechanism
+        finder = doctest.DocTestFinder()
+        optionflags = get_optionflags(self)
+        runner = _get_runner(
+            verbose=0,
+            optionflags=optionflags,
+            checker=_get_checker(),
+            continue_on_failure=_get_continue_on_failure(self.config),
+        )
+
+        for test in finder.find(module, module.__name__):
+            if test.examples:  # skip empty doctests
+                yield DoctestItem(test.name, self, runner, test)
+
+
+def _setup_fixtures(doctest_item):
+    """
+    Used by DoctestTextfile and DoctestItem to setup fixture information.
+    """
+
+    def func():
+        pass
+
+    doctest_item.funcargs = {}
+    fm = doctest_item.session._fixturemanager
+    doctest_item._fixtureinfo = fm.getfixtureinfo(
+        node=doctest_item, func=func, cls=None, funcargs=False
+    )
+    fixture_request = FixtureRequest(doctest_item)
+    fixture_request._fillfixtures()
+    return fixture_request
+
+
+def _get_checker():
+    """
+    Returns a doctest.OutputChecker subclass that takes in account the
+    ALLOW_UNICODE option to ignore u'' prefixes in strings and ALLOW_BYTES
+    to strip b'' prefixes.
+    Useful when the same doctest should run in Python 2 and Python 3.
+
+    An inner class is used to avoid importing "doctest" at the module
+    level.
+    """
+    if hasattr(_get_checker, "LiteralsOutputChecker"):
+        return _get_checker.LiteralsOutputChecker()
+
+    import doctest
+    import re
+
+    class LiteralsOutputChecker(doctest.OutputChecker):
+        """
+        Copied from doctest_nose_plugin.py from the nltk project:
+            https://github.com/nltk/nltk
+
+        Further extended to also support byte literals.
+        """
+
+        _unicode_literal_re = re.compile(r"(\W|^)[uU]([rR]?[\'\"])", re.UNICODE)
+        _bytes_literal_re = re.compile(r"(\W|^)[bB]([rR]?[\'\"])", re.UNICODE)
+
+        def check_output(self, want, got, optionflags):
+            res = doctest.OutputChecker.check_output(self, want, got, optionflags)
+            if res:
+                return True
+
+            allow_unicode = optionflags & _get_allow_unicode_flag()
+            allow_bytes = optionflags & _get_allow_bytes_flag()
+            if not allow_unicode and not allow_bytes:
+                return False
+
+            else:  # pragma: no cover
+
+                def remove_prefixes(regex, txt):
+                    return re.sub(regex, r"\1\2", txt)
+
+                if allow_unicode:
+                    want = remove_prefixes(self._unicode_literal_re, want)
+                    got = remove_prefixes(self._unicode_literal_re, got)
+                if allow_bytes:
+                    want = remove_prefixes(self._bytes_literal_re, want)
+                    got = remove_prefixes(self._bytes_literal_re, got)
+                res = doctest.OutputChecker.check_output(self, want, got, optionflags)
+                return res
+
+    _get_checker.LiteralsOutputChecker = LiteralsOutputChecker
+    return _get_checker.LiteralsOutputChecker()
+
+
+def _get_allow_unicode_flag():
+    """
+    Registers and returns the ALLOW_UNICODE flag.
+    """
+    import doctest
+
+    return doctest.register_optionflag("ALLOW_UNICODE")
+
+
+def _get_allow_bytes_flag():
+    """
+    Registers and returns the ALLOW_BYTES flag.
+    """
+    import doctest
+
+    return doctest.register_optionflag("ALLOW_BYTES")
+
+
+def _get_report_choice(key):
+    """
+    This function returns the actual `doctest` module flag value, we want to do it as late as possible to avoid
+    importing `doctest` and all its dependencies when parsing options, as it adds overhead and breaks tests.
+    """
+    import doctest
+
+    return {
+        DOCTEST_REPORT_CHOICE_UDIFF: doctest.REPORT_UDIFF,
+        DOCTEST_REPORT_CHOICE_CDIFF: doctest.REPORT_CDIFF,
+        DOCTEST_REPORT_CHOICE_NDIFF: doctest.REPORT_NDIFF,
+        DOCTEST_REPORT_CHOICE_ONLY_FIRST_FAILURE: doctest.REPORT_ONLY_FIRST_FAILURE,
+        DOCTEST_REPORT_CHOICE_NONE: 0,
+    }[key]
+
+
+def _fix_spoof_python2(runner, encoding):
+    """
+    Installs a "SpoofOut" into the given DebugRunner so it properly deals with unicode output. This
+    should patch only doctests for text files because they don't have a way to declare their
+    encoding. Doctests in docstrings from Python modules don't have the same problem given that
+    Python already decoded the strings.
+
+    This fixes the problem related in issue #2434.
+    """
+    from _pytest.compat import _PY2
+
+    if not _PY2:
+        return
+
+    from doctest import _SpoofOut
+
+    class UnicodeSpoof(_SpoofOut):
+        def getvalue(self):
+            result = _SpoofOut.getvalue(self)
+            if encoding and isinstance(result, bytes):
+                result = result.decode(encoding)
+            return result
+
+    runner._fakeout = UnicodeSpoof()
+
+
+@pytest.fixture(scope="session")
+def doctest_namespace():
+    """
+    Fixture that returns a :py:class:`dict` that will be injected into the namespace of doctests.
+    """
+    return dict()

src/_pytest/experiments.py

@@ -0,0 +1,13 @@
+class PytestExerimentalApiWarning(FutureWarning):
+    "warning category used to denote experiments in pytest"
+
+    @classmethod
+    def simple(cls, apiname):
+        return cls(
+            "{apiname} is an experimental api that may change over time".format(
+                apiname=apiname
+            )
+        )
+
+
+PYTESTER_COPY_EXAMPLE = PytestExerimentalApiWarning.simple("testdir.copy_example")

src/_pytest/freeze_support.py

@@ -0,0 +1,45 @@
+"""
+Provides a function to report all internal modules for using freezing tools
+pytest
+"""
+from __future__ import absolute_import, division, print_function
+
+
+def freeze_includes():
+    """
+    Returns a list of module names used by pytest that should be
+    included by cx_freeze.
+    """
+    import py
+    import _pytest
+
+    result = list(_iter_all_modules(py))
+    result += list(_iter_all_modules(_pytest))
+    return result
+
+
+def _iter_all_modules(package, prefix=""):
+    """
+    Iterates over the names of all modules that can be found in the given
+    package, recursively.
+    Example:
+        _iter_all_modules(_pytest) ->
+            ['_pytest.assertion.newinterpret',
+             '_pytest.capture',
+             '_pytest.core',
+             ...
+            ]
+    """
+    import os
+    import pkgutil
+
+    if type(package) is not str:
+        path, prefix = package.__path__[0], package.__name__ + "."
+    else:
+        path = package
+    for _, name, is_package in pkgutil.iter_modules([path]):
+        if is_package:
+            for m in _iter_all_modules(os.path.join(path, name), prefix=name + "."):
+                yield prefix + m
+        else:
+            yield prefix + name

src/_pytest/helpconfig.py

@@ -0,0 +1,212 @@
+""" version info, help messages, tracing configuration.  """
+from __future__ import absolute_import, division, print_function
+
+import py
+import pytest
+from _pytest.config import PrintHelp
+import os
+import sys
+from argparse import Action
+
+
+class HelpAction(Action):
+    """This is an argparse Action that will raise an exception in
+    order to skip the rest of the argument parsing when --help is passed.
+    This prevents argparse from quitting due to missing required arguments
+    when any are defined, for example by ``pytest_addoption``.
+    This is similar to the way that the builtin argparse --help option is
+    implemented by raising SystemExit.
+    """
+
+    def __init__(self, option_strings, dest=None, default=False, help=None):
+        super(HelpAction, self).__init__(
+            option_strings=option_strings,
+            dest=dest,
+            const=True,
+            default=default,
+            nargs=0,
+            help=help,
+        )
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        setattr(namespace, self.dest, self.const)
+
+        # We should only skip the rest of the parsing after preparse is done
+        if getattr(parser._parser, "after_preparse", False):
+            raise PrintHelp
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("debugconfig")
+    group.addoption(
+        "--version",
+        action="store_true",
+        help="display pytest lib version and import information.",
+    )
+    group._addoption(
+        "-h",
+        "--help",
+        action=HelpAction,
+        dest="help",
+        help="show help message and configuration info",
+    )
+    group._addoption(
+        "-p",
+        action="append",
+        dest="plugins",
+        default=[],
+        metavar="name",
+        help="early-load given plugin (multi-allowed). "
+        "To avoid loading of plugins, use the `no:` prefix, e.g. "
+        "`no:doctest`.",
+    )
+    group.addoption(
+        "--traceconfig",
+        "--trace-config",
+        action="store_true",
+        default=False,
+        help="trace considerations of conftest.py files.",
+    ),
+    group.addoption(
+        "--debug",
+        action="store_true",
+        dest="debug",
+        default=False,
+        help="store internal tracing debug information in 'pytestdebug.log'.",
+    )
+    group._addoption(
+        "-o",
+        "--override-ini",
+        dest="override_ini",
+        action="append",
+        help='override ini option with "option=value" style, e.g. `-o xfail_strict=True -o cache_dir=cache`.',
+    )
+
+
+@pytest.hookimpl(hookwrapper=True)
+def pytest_cmdline_parse():
+    outcome = yield
+    config = outcome.get_result()
+    if config.option.debug:
+        path = os.path.abspath("pytestdebug.log")
+        debugfile = open(path, "w")
+        debugfile.write(
+            "versions pytest-%s, py-%s, "
+            "python-%s\ncwd=%s\nargs=%s\n\n"
+            % (
+                pytest.__version__,
+                py.__version__,
+                ".".join(map(str, sys.version_info)),
+                os.getcwd(),
+                config._origargs,
+            )
+        )
+        config.trace.root.setwriter(debugfile.write)
+        undo_tracing = config.pluginmanager.enable_tracing()
+        sys.stderr.write("writing pytestdebug information to %s\n" % path)
+
+        def unset_tracing():
+            debugfile.close()
+            sys.stderr.write("wrote pytestdebug information to %s\n" % debugfile.name)
+            config.trace.root.setwriter(None)
+            undo_tracing()
+
+        config.add_cleanup(unset_tracing)
+
+
+def pytest_cmdline_main(config):
+    if config.option.version:
+        p = py.path.local(pytest.__file__)
+        sys.stderr.write(
+            "This is pytest version %s, imported from %s\n" % (pytest.__version__, p)
+        )
+        plugininfo = getpluginversioninfo(config)
+        if plugininfo:
+            for line in plugininfo:
+                sys.stderr.write(line + "\n")
+        return 0
+    elif config.option.help:
+        config._do_configure()
+        showhelp(config)
+        config._ensure_unconfigure()
+        return 0
+
+
+def showhelp(config):
+    reporter = config.pluginmanager.get_plugin("terminalreporter")
+    tw = reporter._tw
+    tw.write(config._parser.optparser.format_help())
+    tw.line()
+    tw.line()
+    tw.line(
+        "[pytest] ini-options in the first " "pytest.ini|tox.ini|setup.cfg file found:"
+    )
+    tw.line()
+
+    for name in config._parser._ininames:
+        help, type, default = config._parser._inidict[name]
+        if type is None:
+            type = "string"
+        spec = "%s (%s)" % (name, type)
+        line = "  %-24s %s" % (spec, help)
+        tw.line(line[: tw.fullwidth])
+
+    tw.line()
+    tw.line("environment variables:")
+    vars = [
+        ("PYTEST_ADDOPTS", "extra command line options"),
+        ("PYTEST_PLUGINS", "comma-separated plugins to load during startup"),
+        ("PYTEST_DEBUG", "set to enable debug tracing of pytest's internals"),
+    ]
+    for name, help in vars:
+        tw.line("  %-24s %s" % (name, help))
+    tw.line()
+    tw.line()
+
+    tw.line("to see available markers type: pytest --markers")
+    tw.line("to see available fixtures type: pytest --fixtures")
+    tw.line(
+        "(shown according to specified file_or_dir or current dir "
+        "if not specified; fixtures with leading '_' are only shown "
+        "with the '-v' option"
+    )
+
+    for warningreport in reporter.stats.get("warnings", []):
+        tw.line("warning : " + warningreport.message, red=True)
+    return
+
+
+conftest_options = [("pytest_plugins", "list of plugin names to load")]
+
+
+def getpluginversioninfo(config):
+    lines = []
+    plugininfo = config.pluginmanager.list_plugin_distinfo()
+    if plugininfo:
+        lines.append("setuptools registered plugins:")
+        for plugin, dist in plugininfo:
+            loc = getattr(plugin, "__file__", repr(plugin))
+            content = "%s-%s at %s" % (dist.project_name, dist.version, loc)
+            lines.append("  " + content)
+    return lines
+
+
+def pytest_report_header(config):
+    lines = []
+    if config.option.debug or config.option.traceconfig:
+        lines.append("using: pytest-%s pylib-%s" % (pytest.__version__, py.__version__))
+
+        verinfo = getpluginversioninfo(config)
+        if verinfo:
+            lines.extend(verinfo)
+
+    if config.option.traceconfig:
+        lines.append("active plugins:")
+        items = config.pluginmanager.list_name_plugin()
+        for name, plugin in items:
+            if hasattr(plugin, "__file__"):
+                r = plugin.__file__
+            else:
+                r = repr(plugin)
+            lines.append("    %-20s: %s" % (name, r))
+    return lines

src/_pytest/hookspec.py

@@ -0,0 +1,563 @@
+""" hook specifications for pytest plugins, invoked from main.py and builtin plugins.  """
+
+from pluggy import HookspecMarker
+
+hookspec = HookspecMarker("pytest")
+
+# -------------------------------------------------------------------------
+# Initialization hooks called for every plugin
+# -------------------------------------------------------------------------
+
+
+@hookspec(historic=True)
+def pytest_addhooks(pluginmanager):
+    """called at plugin registration time to allow adding new hooks via a call to
+    ``pluginmanager.add_hookspecs(module_or_class, prefix)``.
+
+
+    :param _pytest.config.PytestPluginManager pluginmanager: pytest plugin manager
+
+    .. note::
+        This hook is incompatible with ``hookwrapper=True``.
+    """
+
+
+@hookspec(historic=True)
+def pytest_namespace():
+    """
+    (**Deprecated**) this hook causes direct monkeypatching on pytest, its use is strongly discouraged
+    return dict of name->object to be made globally available in
+    the pytest namespace.
+
+    This hook is called at plugin registration time.
+
+    .. note::
+        This hook is incompatible with ``hookwrapper=True``.
+    """
+
+
+@hookspec(historic=True)
+def pytest_plugin_registered(plugin, manager):
+    """ a new pytest plugin got registered.
+
+    :param plugin: the plugin module or instance
+    :param _pytest.config.PytestPluginManager manager: pytest plugin manager
+
+    .. note::
+        This hook is incompatible with ``hookwrapper=True``.
+    """
+
+
+@hookspec(historic=True)
+def pytest_addoption(parser):
+    """register argparse-style options and ini-style config values,
+    called once at the beginning of a test run.
+
+    .. note::
+
+        This function should be implemented only in plugins or ``conftest.py``
+        files situated at the tests root directory due to how pytest
+        :ref:`discovers plugins during startup <pluginorder>`.
+
+    :arg _pytest.config.Parser parser: To add command line options, call
+        :py:func:`parser.addoption(...) <_pytest.config.Parser.addoption>`.
+        To add ini-file values call :py:func:`parser.addini(...)
+        <_pytest.config.Parser.addini>`.
+
+    Options can later be accessed through the
+    :py:class:`config <_pytest.config.Config>` object, respectively:
+
+    - :py:func:`config.getoption(name) <_pytest.config.Config.getoption>` to
+      retrieve the value of a command line option.
+
+    - :py:func:`config.getini(name) <_pytest.config.Config.getini>` to retrieve
+      a value read from an ini-style file.
+
+    The config object is passed around on many internal objects via the ``.config``
+    attribute or can be retrieved as the ``pytestconfig`` fixture.
+
+    .. note::
+        This hook is incompatible with ``hookwrapper=True``.
+    """
+
+
+@hookspec(historic=True)
+def pytest_configure(config):
+    """
+    Allows plugins and conftest files to perform initial configuration.
+
+    This hook is called for every plugin and initial conftest file
+    after command line options have been parsed.
+
+    After that, the hook is called for other conftest files as they are
+    imported.
+
+    .. note::
+        This hook is incompatible with ``hookwrapper=True``.
+
+    :arg _pytest.config.Config config: pytest config object
+    """
+
+
+# -------------------------------------------------------------------------
+# Bootstrapping hooks called for plugins registered early enough:
+# internal and 3rd party plugins.
+# -------------------------------------------------------------------------
+
+
+@hookspec(firstresult=True)
+def pytest_cmdline_parse(pluginmanager, args):
+    """return initialized config object, parsing the specified args.
+
+    Stops at first non-None result, see :ref:`firstresult`
+
+    .. note::
+        This hook will not be called for ``conftest.py`` files, only for setuptools plugins.
+
+    :param _pytest.config.PytestPluginManager pluginmanager: pytest plugin manager
+    :param list[str] args: list of arguments passed on the command line
+    """
+
+
+def pytest_cmdline_preparse(config, args):
+    """(**Deprecated**) modify command line arguments before option parsing.
+
+    This hook is considered deprecated and will be removed in a future pytest version. Consider
+    using :func:`pytest_load_initial_conftests` instead.
+
+    .. note::
+        This hook will not be called for ``conftest.py`` files, only for setuptools plugins.
+
+    :param _pytest.config.Config config: pytest config object
+    :param list[str] args: list of arguments passed on the command line
+    """
+
+
+@hookspec(firstresult=True)
+def pytest_cmdline_main(config):
+    """ called for performing the main command line action. The default
+    implementation will invoke the configure hooks and runtest_mainloop.
+
+    .. note::
+        This hook will not be called for ``conftest.py`` files, only for setuptools plugins.
+
+    Stops at first non-None result, see :ref:`firstresult`
+
+    :param _pytest.config.Config config: pytest config object
+    """
+
+
+def pytest_load_initial_conftests(early_config, parser, args):
+    """ implements the loading of initial conftest files ahead
+    of command line option parsing.
+
+    .. note::
+        This hook will not be called for ``conftest.py`` files, only for setuptools plugins.
+
+    :param _pytest.config.Config early_config: pytest config object
+    :param list[str] args: list of arguments passed on the command line
+    :param _pytest.config.Parser parser: to add command line options
+    """
+
+
+# -------------------------------------------------------------------------
+# collection hooks
+# -------------------------------------------------------------------------
+
+
+@hookspec(firstresult=True)
+def pytest_collection(session):
+    """Perform the collection protocol for the given session.
+
+    Stops at first non-None result, see :ref:`firstresult`.
+
+    :param _pytest.main.Session session: the pytest session object
+    """
+
+
+def pytest_collection_modifyitems(session, config, items):
+    """ called after collection has been performed, may filter or re-order
+    the items in-place.
+
+    :param _pytest.main.Session session: the pytest session object
+    :param _pytest.config.Config config: pytest config object
+    :param List[_pytest.nodes.Item] items: list of item objects
+    """
+
+
+def pytest_collection_finish(session):
+    """ called after collection has been performed and modified.
+
+    :param _pytest.main.Session session: the pytest session object
+    """
+
+
+@hookspec(firstresult=True)
+def pytest_ignore_collect(path, config):
+    """ return True to prevent considering this path for collection.
+    This hook is consulted for all files and directories prior to calling
+    more specific hooks.
+
+    Stops at first non-None result, see :ref:`firstresult`
+
+    :param str path: the path to analyze
+    :param _pytest.config.Config config: pytest config object
+    """
+
+
+@hookspec(firstresult=True)
+def pytest_collect_directory(path, parent):
+    """ called before traversing a directory for collection files.
+
+    Stops at first non-None result, see :ref:`firstresult`
+
+    :param str path: the path to analyze
+    """
+
+
+def pytest_collect_file(path, parent):
+    """ return collection Node or None for the given path. Any new node
+    needs to have the specified ``parent`` as a parent.
+
+    :param str path: the path to collect
+    """
+
+
+# logging hooks for collection
+
+
+def pytest_collectstart(collector):
+    """ collector starts collecting. """
+
+
+def pytest_itemcollected(item):
+    """ we just collected a test item. """
+
+
+def pytest_collectreport(report):
+    """ collector finished collecting. """
+
+
+def pytest_deselected(items):
+    """ called for test items deselected by keyword. """
+
+
+@hookspec(firstresult=True)
+def pytest_make_collect_report(collector):
+    """ perform ``collector.collect()`` and return a CollectReport.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
+
+# -------------------------------------------------------------------------
+# Python test function related hooks
+# -------------------------------------------------------------------------
+
+
+@hookspec(firstresult=True)
+def pytest_pycollect_makemodule(path, parent):
+    """ return a Module collector or None for the given path.
+    This hook will be called for each matching test module path.
+    The pytest_collect_file hook needs to be used if you want to
+    create test modules for files that do not match as a test module.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
+
+@hookspec(firstresult=True)
+def pytest_pycollect_makeitem(collector, name, obj):
+    """ return custom item/collector for a python object in a module, or None.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
+
+@hookspec(firstresult=True)
+def pytest_pyfunc_call(pyfuncitem):
+    """ call underlying test function.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
+
+def pytest_generate_tests(metafunc):
+    """ generate (multiple) parametrized calls to a test function."""
+
+
+@hookspec(firstresult=True)
+def pytest_make_parametrize_id(config, val, argname):
+    """Return a user-friendly string representation of the given ``val`` that will be used
+    by @pytest.mark.parametrize calls. Return None if the hook doesn't know about ``val``.
+    The parameter name is available as ``argname``, if required.
+
+    Stops at first non-None result, see :ref:`firstresult`
+
+    :param _pytest.config.Config config: pytest config object
+    :param val: the parametrized value
+    :param str argname: the automatic parameter name produced by pytest
+    """
+
+
+# -------------------------------------------------------------------------
+# generic runtest related hooks
+# -------------------------------------------------------------------------
+
+
+@hookspec(firstresult=True)
+def pytest_runtestloop(session):
+    """ called for performing the main runtest loop
+    (after collection finished).
+
+    Stops at first non-None result, see :ref:`firstresult`
+
+    :param _pytest.main.Session session: the pytest session object
+    """
+
+
+def pytest_itemstart(item, node):
+    """(**Deprecated**) use pytest_runtest_logstart. """
+
+
+@hookspec(firstresult=True)
+def pytest_runtest_protocol(item, nextitem):
+    """ implements the runtest_setup/call/teardown protocol for
+    the given test item, including capturing exceptions and calling
+    reporting hooks.
+
+    :arg item: test item for which the runtest protocol is performed.
+
+    :arg nextitem: the scheduled-to-be-next test item (or None if this
+                   is the end my friend).  This argument is passed on to
+                   :py:func:`pytest_runtest_teardown`.
+
+    :return boolean: True if no further hook implementations should be invoked.
+
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
+
+def pytest_runtest_logstart(nodeid, location):
+    """ signal the start of running a single test item.
+
+    This hook will be called **before** :func:`pytest_runtest_setup`, :func:`pytest_runtest_call` and
+    :func:`pytest_runtest_teardown` hooks.
+
+    :param str nodeid: full id of the item
+    :param location: a triple of ``(filename, linenum, testname)``
+    """
+
+
+def pytest_runtest_logfinish(nodeid, location):
+    """ signal the complete finish of running a single test item.
+
+    This hook will be called **after** :func:`pytest_runtest_setup`, :func:`pytest_runtest_call` and
+    :func:`pytest_runtest_teardown` hooks.
+
+    :param str nodeid: full id of the item
+    :param location: a triple of ``(filename, linenum, testname)``
+    """
+
+
+def pytest_runtest_setup(item):
+    """ called before ``pytest_runtest_call(item)``. """
+
+
+def pytest_runtest_call(item):
+    """ called to execute the test ``item``. """
+
+
+def pytest_runtest_teardown(item, nextitem):
+    """ called after ``pytest_runtest_call``.
+
+    :arg nextitem: the scheduled-to-be-next test item (None if no further
+                   test item is scheduled).  This argument can be used to
+                   perform exact teardowns, i.e. calling just enough finalizers
+                   so that nextitem only needs to call setup-functions.
+    """
+
+
+@hookspec(firstresult=True)
+def pytest_runtest_makereport(item, call):
+    """ return a :py:class:`_pytest.runner.TestReport` object
+    for the given :py:class:`pytest.Item <_pytest.main.Item>` and
+    :py:class:`_pytest.runner.CallInfo`.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
+
+def pytest_runtest_logreport(report):
+    """ process a test setup/call/teardown report relating to
+    the respective phase of executing a test. """
+
+
+# -------------------------------------------------------------------------
+# Fixture related hooks
+# -------------------------------------------------------------------------
+
+
+@hookspec(firstresult=True)
+def pytest_fixture_setup(fixturedef, request):
+    """ performs fixture setup execution.
+
+    :return: The return value of the call to the fixture function
+
+    Stops at first non-None result, see :ref:`firstresult`
+
+    .. note::
+        If the fixture function returns None, other implementations of
+        this hook function will continue to be called, according to the
+        behavior of the :ref:`firstresult` option.
+    """
+
+
+def pytest_fixture_post_finalizer(fixturedef, request):
+    """ called after fixture teardown, but before the cache is cleared so
+    the fixture result cache ``fixturedef.cached_result`` can
+    still be accessed."""
+
+
+# -------------------------------------------------------------------------
+# test session related hooks
+# -------------------------------------------------------------------------
+
+
+def pytest_sessionstart(session):
+    """ called after the ``Session`` object has been created and before performing collection
+    and entering the run test loop.
+
+    :param _pytest.main.Session session: the pytest session object
+    """
+
+
+def pytest_sessionfinish(session, exitstatus):
+    """ called after whole test run finished, right before returning the exit status to the system.
+
+    :param _pytest.main.Session session: the pytest session object
+    :param int exitstatus: the status which pytest will return to the system
+    """
+
+
+def pytest_unconfigure(config):
+    """ called before test process is exited.
+
+    :param _pytest.config.Config config: pytest config object
+    """
+
+
+# -------------------------------------------------------------------------
+# hooks for customizing the assert methods
+# -------------------------------------------------------------------------
+
+
+def pytest_assertrepr_compare(config, op, left, right):
+    """return explanation for comparisons in failing assert expressions.
+
+    Return None for no custom explanation, otherwise return a list
+    of strings.  The strings will be joined by newlines but any newlines
+    *in* a string will be escaped.  Note that all but the first line will
+    be indented slightly, the intention is for the first line to be a summary.
+
+    :param _pytest.config.Config config: pytest config object
+    """
+
+
+# -------------------------------------------------------------------------
+# hooks for influencing reporting (invoked from _pytest_terminal)
+# -------------------------------------------------------------------------
+
+
+def pytest_report_header(config, startdir):
+    """ return a string or list of strings to be displayed as header info for terminal reporting.
+
+    :param _pytest.config.Config config: pytest config object
+    :param startdir: py.path object with the starting dir
+
+    .. note::
+
+        This function should be implemented only in plugins or ``conftest.py``
+        files situated at the tests root directory due to how pytest
+        :ref:`discovers plugins during startup <pluginorder>`.
+    """
+
+
+def pytest_report_collectionfinish(config, startdir, items):
+    """
+    .. versionadded:: 3.2
+
+    return a string or list of strings to be displayed after collection has finished successfully.
+
+    This strings will be displayed after the standard "collected X items" message.
+
+    :param _pytest.config.Config config: pytest config object
+    :param startdir: py.path object with the starting dir
+    :param items: list of pytest items that are going to be executed; this list should not be modified.
+    """
+
+
+@hookspec(firstresult=True)
+def pytest_report_teststatus(report):
+    """ return result-category, shortletter and verbose word for reporting.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
+
+def pytest_terminal_summary(terminalreporter, exitstatus):
+    """Add a section to terminal summary reporting.
+
+    :param _pytest.terminal.TerminalReporter terminalreporter: the internal terminal reporter object
+    :param int exitstatus: the exit status that will be reported back to the OS
+
+    .. versionadded:: 3.5
+        The ``config`` parameter.
+    """
+
+
+@hookspec(historic=True)
+def pytest_logwarning(message, code, nodeid, fslocation):
+    """ process a warning specified by a message, a code string,
+    a nodeid and fslocation (both of which may be None
+    if the warning is not tied to a particular node/location).
+
+    .. note::
+        This hook is incompatible with ``hookwrapper=True``.
+    """
+
+
+# -------------------------------------------------------------------------
+# doctest hooks
+# -------------------------------------------------------------------------
+
+
+@hookspec(firstresult=True)
+def pytest_doctest_prepare_content(content):
+    """ return processed content for a given doctest
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
+
+# -------------------------------------------------------------------------
+# error handling and internal debugging hooks
+# -------------------------------------------------------------------------
+
+
+def pytest_internalerror(excrepr, excinfo):
+    """ called for internal errors. """
+
+
+def pytest_keyboard_interrupt(excinfo):
+    """ called for keyboard interrupt. """
+
+
+def pytest_exception_interact(node, call, report):
+    """called when an exception was raised which can potentially be
+    interactively handled.
+
+    This hook is only called if an exception was raised
+    that is not an internal exception like ``skip.Exception``.
+    """
+
+
+def pytest_enter_pdb(config):
+    """ called upon pdb.set_trace(), can be used by plugins to take special
+    action just before the python debugger enters in interactive mode.
+
+    :param _pytest.config.Config config: pytest config object
+    """

src/_pytest/junitxml.py

@@ -0,0 +1,564 @@
+"""
+    report test results in JUnit-XML format,
+    for use with Jenkins and build integration servers.
+
+
+Based on initial code from Ross Lawley.
+
+Output conforms to https://github.com/jenkinsci/xunit-plugin/blob/master/
+src/main/resources/org/jenkinsci/plugins/xunit/types/model/xsd/junit-10.xsd
+"""
+from __future__ import absolute_import, division, print_function
+
+import functools
+import py
+import os
+import re
+import sys
+import time
+import pytest
+from _pytest import nodes
+from _pytest.config import filename_arg
+
+# Python 2.X and 3.X compatibility
+if sys.version_info[0] < 3:
+    from codecs import open
+else:
+    unichr = chr
+    unicode = str
+    long = int
+
+
+class Junit(py.xml.Namespace):
+    pass
+
+
+# We need to get the subset of the invalid unicode ranges according to
+# XML 1.0 which are valid in this python build.  Hence we calculate
+# this dynamically instead of hardcoding it.  The spec range of valid
+# chars is: Char ::= #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD]
+#                    | [#x10000-#x10FFFF]
+_legal_chars = (0x09, 0x0A, 0x0d)
+_legal_ranges = ((0x20, 0x7E), (0x80, 0xD7FF), (0xE000, 0xFFFD), (0x10000, 0x10FFFF))
+_legal_xml_re = [
+    unicode("%s-%s") % (unichr(low), unichr(high))
+    for (low, high) in _legal_ranges
+    if low < sys.maxunicode
+]
+_legal_xml_re = [unichr(x) for x in _legal_chars] + _legal_xml_re
+illegal_xml_re = re.compile(unicode("[^%s]") % unicode("").join(_legal_xml_re))
+del _legal_chars
+del _legal_ranges
+del _legal_xml_re
+
+_py_ext_re = re.compile(r"\.py$")
+
+
+def bin_xml_escape(arg):
+    def repl(matchobj):
+        i = ord(matchobj.group())
+        if i <= 0xFF:
+            return unicode("#x%02X") % i
+        else:
+            return unicode("#x%04X") % i
+
+    return py.xml.raw(illegal_xml_re.sub(repl, py.xml.escape(arg)))
+
+
+class _NodeReporter(object):
+    def __init__(self, nodeid, xml):
+
+        self.id = nodeid
+        self.xml = xml
+        self.add_stats = self.xml.add_stats
+        self.duration = 0
+        self.properties = []
+        self.nodes = []
+        self.testcase = None
+        self.attrs = {}
+
+    def append(self, node):
+        self.xml.add_stats(type(node).__name__)
+        self.nodes.append(node)
+
+    def add_property(self, name, value):
+        self.properties.append((str(name), bin_xml_escape(value)))
+
+    def add_attribute(self, name, value):
+        self.attrs[str(name)] = bin_xml_escape(value)
+
+    def make_properties_node(self):
+        """Return a Junit node containing custom properties, if any.
+        """
+        if self.properties:
+            return Junit.properties(
+                [
+                    Junit.property(name=name, value=value)
+                    for name, value in self.properties
+                ]
+            )
+        return ""
+
+    def record_testreport(self, testreport):
+        assert not self.testcase
+        names = mangle_test_address(testreport.nodeid)
+        existing_attrs = self.attrs
+        classnames = names[:-1]
+        if self.xml.prefix:
+            classnames.insert(0, self.xml.prefix)
+        attrs = {
+            "classname": ".".join(classnames),
+            "name": bin_xml_escape(names[-1]),
+            "file": testreport.location[0],
+        }
+        if testreport.location[1] is not None:
+            attrs["line"] = testreport.location[1]
+        if hasattr(testreport, "url"):
+            attrs["url"] = testreport.url
+        self.attrs = attrs
+        self.attrs.update(existing_attrs)  # restore any user-defined attributes
+
+    def to_xml(self):
+        testcase = Junit.testcase(time=self.duration, **self.attrs)
+        testcase.append(self.make_properties_node())
+        for node in self.nodes:
+            testcase.append(node)
+        return testcase
+
+    def _add_simple(self, kind, message, data=None):
+        data = bin_xml_escape(data)
+        node = kind(data, message=message)
+        self.append(node)
+
+    def write_captured_output(self, report):
+        content_out = report.capstdout
+        content_log = report.caplog
+        content_err = report.capstderr
+
+        if content_log or content_out:
+            if content_log and self.xml.logging == "system-out":
+                if content_out:
+                    # syncing stdout and the log-output is not done yet. It's
+                    # probably not worth the effort. Therefore, first the captured
+                    # stdout is shown and then the captured logs.
+                    content = "\n".join(
+                        [
+                            " Captured Stdout ".center(80, "-"),
+                            content_out,
+                            "",
+                            " Captured Log ".center(80, "-"),
+                            content_log,
+                        ]
+                    )
+                else:
+                    content = content_log
+            else:
+                content = content_out
+
+            if content:
+                tag = getattr(Junit, "system-out")
+                self.append(tag(bin_xml_escape(content)))
+
+        if content_log or content_err:
+            if content_log and self.xml.logging == "system-err":
+                if content_err:
+                    content = "\n".join(
+                        [
+                            " Captured Stderr ".center(80, "-"),
+                            content_err,
+                            "",
+                            " Captured Log ".center(80, "-"),
+                            content_log,
+                        ]
+                    )
+                else:
+                    content = content_log
+            else:
+                content = content_err
+
+            if content:
+                tag = getattr(Junit, "system-err")
+                self.append(tag(bin_xml_escape(content)))
+
+    def append_pass(self, report):
+        self.add_stats("passed")
+
+    def append_failure(self, report):
+        # msg = str(report.longrepr.reprtraceback.extraline)
+        if hasattr(report, "wasxfail"):
+            self._add_simple(Junit.skipped, "xfail-marked test passes unexpectedly")
+        else:
+            if hasattr(report.longrepr, "reprcrash"):
+                message = report.longrepr.reprcrash.message
+            elif isinstance(report.longrepr, (unicode, str)):
+                message = report.longrepr
+            else:
+                message = str(report.longrepr)
+            message = bin_xml_escape(message)
+            fail = Junit.failure(message=message)
+            fail.append(bin_xml_escape(report.longrepr))
+            self.append(fail)
+
+    def append_collect_error(self, report):
+        # msg = str(report.longrepr.reprtraceback.extraline)
+        self.append(
+            Junit.error(bin_xml_escape(report.longrepr), message="collection failure")
+        )
+
+    def append_collect_skipped(self, report):
+        self._add_simple(Junit.skipped, "collection skipped", report.longrepr)
+
+    def append_error(self, report):
+        if getattr(report, "when", None) == "teardown":
+            msg = "test teardown failure"
+        else:
+            msg = "test setup failure"
+        self._add_simple(Junit.error, msg, report.longrepr)
+
+    def append_skipped(self, report):
+        if hasattr(report, "wasxfail"):
+            self._add_simple(Junit.skipped, "expected test failure", report.wasxfail)
+        else:
+            filename, lineno, skipreason = report.longrepr
+            if skipreason.startswith("Skipped: "):
+                skipreason = bin_xml_escape(skipreason[9:])
+            self.append(
+                Junit.skipped(
+                    "%s:%s: %s" % (filename, lineno, skipreason),
+                    type="pytest.skip",
+                    message=skipreason,
+                )
+            )
+            self.write_captured_output(report)
+
+    def finalize(self):
+        data = self.to_xml().unicode(indent=0)
+        self.__dict__.clear()
+        self.to_xml = lambda: py.xml.raw(data)
+
+
+@pytest.fixture
+def record_property(request):
+    """Add an extra properties the calling test.
+    User properties become part of the test report and are available to the
+    configured reporters, like JUnit XML.
+    The fixture is callable with ``(name, value)``, with value being automatically
+    xml-encoded.
+
+    Example::
+
+        def test_function(record_property):
+            record_property("example_key", 1)
+    """
+
+    def append_property(name, value):
+        request.node.user_properties.append((name, value))
+
+    return append_property
+
+
+@pytest.fixture
+def record_xml_property(record_property):
+    """(Deprecated) use record_property."""
+    import warnings
+    from _pytest import deprecated
+
+    warnings.warn(deprecated.RECORD_XML_PROPERTY, DeprecationWarning, stacklevel=2)
+
+    return record_property
+
+
+@pytest.fixture
+def record_xml_attribute(request):
+    """Add extra xml attributes to the tag for the calling test.
+    The fixture is callable with ``(name, value)``, with value being
+    automatically xml-encoded
+    """
+    request.node.warn(
+        code="C3", message="record_xml_attribute is an experimental feature"
+    )
+    xml = getattr(request.config, "_xml", None)
+    if xml is not None:
+        node_reporter = xml.node_reporter(request.node.nodeid)
+        return node_reporter.add_attribute
+    else:
+
+        def add_attr_noop(name, value):
+            pass
+
+        return add_attr_noop
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("terminal reporting")
+    group.addoption(
+        "--junitxml",
+        "--junit-xml",
+        action="store",
+        dest="xmlpath",
+        metavar="path",
+        type=functools.partial(filename_arg, optname="--junitxml"),
+        default=None,
+        help="create junit-xml style report file at given path.",
+    )
+    group.addoption(
+        "--junitprefix",
+        "--junit-prefix",
+        action="store",
+        metavar="str",
+        default=None,
+        help="prepend prefix to classnames in junit-xml output",
+    )
+    parser.addini(
+        "junit_suite_name", "Test suite name for JUnit report", default="pytest"
+    )
+    parser.addini(
+        "junit_logging",
+        "Write captured log messages to JUnit report: "
+        "one of no|system-out|system-err",
+        default="no",
+    )  # choices=['no', 'stdout', 'stderr'])
+
+
+def pytest_configure(config):
+    xmlpath = config.option.xmlpath
+    # prevent opening xmllog on slave nodes (xdist)
+    if xmlpath and not hasattr(config, "slaveinput"):
+        config._xml = LogXML(
+            xmlpath,
+            config.option.junitprefix,
+            config.getini("junit_suite_name"),
+            config.getini("junit_logging"),
+        )
+        config.pluginmanager.register(config._xml)
+
+
+def pytest_unconfigure(config):
+    xml = getattr(config, "_xml", None)
+    if xml:
+        del config._xml
+        config.pluginmanager.unregister(xml)
+
+
+def mangle_test_address(address):
+    path, possible_open_bracket, params = address.partition("[")
+    names = path.split("::")
+    try:
+        names.remove("()")
+    except ValueError:
+        pass
+    # convert file path to dotted path
+    names[0] = names[0].replace(nodes.SEP, ".")
+    names[0] = _py_ext_re.sub("", names[0])
+    # put any params back
+    names[-1] += possible_open_bracket + params
+    return names
+
+
+class LogXML(object):
+    def __init__(self, logfile, prefix, suite_name="pytest", logging="no"):
+        logfile = os.path.expanduser(os.path.expandvars(logfile))
+        self.logfile = os.path.normpath(os.path.abspath(logfile))
+        self.prefix = prefix
+        self.suite_name = suite_name
+        self.logging = logging
+        self.stats = dict.fromkeys(["error", "passed", "failure", "skipped"], 0)
+        self.node_reporters = {}  # nodeid -> _NodeReporter
+        self.node_reporters_ordered = []
+        self.global_properties = []
+        # List of reports that failed on call but teardown is pending.
+        self.open_reports = []
+        self.cnt_double_fail_tests = 0
+
+    def finalize(self, report):
+        nodeid = getattr(report, "nodeid", report)
+        # local hack to handle xdist report order
+        slavenode = getattr(report, "node", None)
+        reporter = self.node_reporters.pop((nodeid, slavenode))
+        if reporter is not None:
+            reporter.finalize()
+
+    def node_reporter(self, report):
+        nodeid = getattr(report, "nodeid", report)
+        # local hack to handle xdist report order
+        slavenode = getattr(report, "node", None)
+
+        key = nodeid, slavenode
+
+        if key in self.node_reporters:
+            # TODO: breasks for --dist=each
+            return self.node_reporters[key]
+
+        reporter = _NodeReporter(nodeid, self)
+
+        self.node_reporters[key] = reporter
+        self.node_reporters_ordered.append(reporter)
+
+        return reporter
+
+    def add_stats(self, key):
+        if key in self.stats:
+            self.stats[key] += 1
+
+    def _opentestcase(self, report):
+        reporter = self.node_reporter(report)
+        reporter.record_testreport(report)
+        return reporter
+
+    def pytest_runtest_logreport(self, report):
+        """handle a setup/call/teardown report, generating the appropriate
+        xml tags as necessary.
+
+        note: due to plugins like xdist, this hook may be called in interlaced
+        order with reports from other nodes. for example:
+
+        usual call order:
+            -> setup node1
+            -> call node1
+            -> teardown node1
+            -> setup node2
+            -> call node2
+            -> teardown node2
+
+        possible call order in xdist:
+            -> setup node1
+            -> call node1
+            -> setup node2
+            -> call node2
+            -> teardown node2
+            -> teardown node1
+        """
+        close_report = None
+        if report.passed:
+            if report.when == "call":  # ignore setup/teardown
+                reporter = self._opentestcase(report)
+                reporter.append_pass(report)
+        elif report.failed:
+            if report.when == "teardown":
+                # The following vars are needed when xdist plugin is used
+                report_wid = getattr(report, "worker_id", None)
+                report_ii = getattr(report, "item_index", None)
+                close_report = next(
+                    (
+                        rep
+                        for rep in self.open_reports
+                        if (
+                            rep.nodeid == report.nodeid
+                            and getattr(rep, "item_index", None) == report_ii
+                            and getattr(rep, "worker_id", None) == report_wid
+                        )
+                    ),
+                    None,
+                )
+                if close_report:
+                    # We need to open new testcase in case we have failure in
+                    # call and error in teardown in order to follow junit
+                    # schema
+                    self.finalize(close_report)
+                    self.cnt_double_fail_tests += 1
+            reporter = self._opentestcase(report)
+            if report.when == "call":
+                reporter.append_failure(report)
+                self.open_reports.append(report)
+            else:
+                reporter.append_error(report)
+        elif report.skipped:
+            reporter = self._opentestcase(report)
+            reporter.append_skipped(report)
+        self.update_testcase_duration(report)
+        if report.when == "teardown":
+            reporter = self._opentestcase(report)
+            reporter.write_captured_output(report)
+
+            for propname, propvalue in report.user_properties:
+                reporter.add_property(propname, propvalue)
+
+            self.finalize(report)
+            report_wid = getattr(report, "worker_id", None)
+            report_ii = getattr(report, "item_index", None)
+            close_report = next(
+                (
+                    rep
+                    for rep in self.open_reports
+                    if (
+                        rep.nodeid == report.nodeid
+                        and getattr(rep, "item_index", None) == report_ii
+                        and getattr(rep, "worker_id", None) == report_wid
+                    )
+                ),
+                None,
+            )
+            if close_report:
+                self.open_reports.remove(close_report)
+
+    def update_testcase_duration(self, report):
+        """accumulates total duration for nodeid from given report and updates
+        the Junit.testcase with the new total if already created.
+        """
+        reporter = self.node_reporter(report)
+        reporter.duration += getattr(report, "duration", 0.0)
+
+    def pytest_collectreport(self, report):
+        if not report.passed:
+            reporter = self._opentestcase(report)
+            if report.failed:
+                reporter.append_collect_error(report)
+            else:
+                reporter.append_collect_skipped(report)
+
+    def pytest_internalerror(self, excrepr):
+        reporter = self.node_reporter("internal")
+        reporter.attrs.update(classname="pytest", name="internal")
+        reporter._add_simple(Junit.error, "internal error", excrepr)
+
+    def pytest_sessionstart(self):
+        self.suite_start_time = time.time()
+
+    def pytest_sessionfinish(self):
+        dirname = os.path.dirname(os.path.abspath(self.logfile))
+        if not os.path.isdir(dirname):
+            os.makedirs(dirname)
+        logfile = open(self.logfile, "w", encoding="utf-8")
+        suite_stop_time = time.time()
+        suite_time_delta = suite_stop_time - self.suite_start_time
+
+        numtests = (
+            self.stats["passed"]
+            + self.stats["failure"]
+            + self.stats["skipped"]
+            + self.stats["error"]
+            - self.cnt_double_fail_tests
+        )
+        logfile.write('<?xml version="1.0" encoding="utf-8"?>')
+
+        logfile.write(
+            Junit.testsuite(
+                self._get_global_properties_node(),
+                [x.to_xml() for x in self.node_reporters_ordered],
+                name=self.suite_name,
+                errors=self.stats["error"],
+                failures=self.stats["failure"],
+                skips=self.stats["skipped"],
+                tests=numtests,
+                time="%.3f" % suite_time_delta,
+            ).unicode(indent=0)
+        )
+        logfile.close()
+
+    def pytest_terminal_summary(self, terminalreporter):
+        terminalreporter.write_sep("-", "generated xml file: %s" % (self.logfile))
+
+    def add_global_property(self, name, value):
+        self.global_properties.append((str(name), bin_xml_escape(value)))
+
+    def _get_global_properties_node(self):
+        """Return a Junit node containing custom properties, if any.
+        """
+        if self.global_properties:
+            return Junit.properties(
+                [
+                    Junit.property(name=name, value=value)
+                    for name, value in self.global_properties
+                ]
+            )
+        return ""

src/_pytest/logging.py

@@ -0,0 +1,591 @@
+""" Access and control log capturing. """
+from __future__ import absolute_import, division, print_function
+
+import logging
+from contextlib import closing, contextmanager
+import re
+import six
+
+from _pytest.config import create_terminal_writer
+import pytest
+import py
+
+
+DEFAULT_LOG_FORMAT = "%(filename)-25s %(lineno)4d %(levelname)-8s %(message)s"
+DEFAULT_LOG_DATE_FORMAT = "%H:%M:%S"
+
+
+class ColoredLevelFormatter(logging.Formatter):
+    """
+    Colorize the %(levelname)..s part of the log format passed to __init__.
+    """
+
+    LOGLEVEL_COLOROPTS = {
+        logging.CRITICAL: {"red"},
+        logging.ERROR: {"red", "bold"},
+        logging.WARNING: {"yellow"},
+        logging.WARN: {"yellow"},
+        logging.INFO: {"green"},
+        logging.DEBUG: {"purple"},
+        logging.NOTSET: set(),
+    }
+    LEVELNAME_FMT_REGEX = re.compile(r"%\(levelname\)([+-]?\d*s)")
+
+    def __init__(self, terminalwriter, *args, **kwargs):
+        super(ColoredLevelFormatter, self).__init__(*args, **kwargs)
+        if six.PY2:
+            self._original_fmt = self._fmt
+        else:
+            self._original_fmt = self._style._fmt
+        self._level_to_fmt_mapping = {}
+
+        levelname_fmt_match = self.LEVELNAME_FMT_REGEX.search(self._fmt)
+        if not levelname_fmt_match:
+            return
+        levelname_fmt = levelname_fmt_match.group()
+
+        for level, color_opts in self.LOGLEVEL_COLOROPTS.items():
+            formatted_levelname = levelname_fmt % {
+                "levelname": logging.getLevelName(level)
+            }
+
+            # add ANSI escape sequences around the formatted levelname
+            color_kwargs = {name: True for name in color_opts}
+            colorized_formatted_levelname = terminalwriter.markup(
+                formatted_levelname, **color_kwargs
+            )
+            self._level_to_fmt_mapping[level] = self.LEVELNAME_FMT_REGEX.sub(
+                colorized_formatted_levelname, self._fmt
+            )
+
+    def format(self, record):
+        fmt = self._level_to_fmt_mapping.get(record.levelno, self._original_fmt)
+        if six.PY2:
+            self._fmt = fmt
+        else:
+            self._style._fmt = fmt
+        return super(ColoredLevelFormatter, self).format(record)
+
+
+def get_option_ini(config, *names):
+    for name in names:
+        ret = config.getoption(name)  # 'default' arg won't work as expected
+        if ret is None:
+            ret = config.getini(name)
+        if ret:
+            return ret
+
+
+def pytest_addoption(parser):
+    """Add options to control log capturing."""
+    group = parser.getgroup("logging")
+
+    def add_option_ini(option, dest, default=None, type=None, **kwargs):
+        parser.addini(
+            dest, default=default, type=type, help="default value for " + option
+        )
+        group.addoption(option, dest=dest, **kwargs)
+
+    add_option_ini(
+        "--no-print-logs",
+        dest="log_print",
+        action="store_const",
+        const=False,
+        default=True,
+        type="bool",
+        help="disable printing caught logs on failed tests.",
+    )
+    add_option_ini(
+        "--log-level",
+        dest="log_level",
+        default=None,
+        help="logging level used by the logging module",
+    )
+    add_option_ini(
+        "--log-format",
+        dest="log_format",
+        default=DEFAULT_LOG_FORMAT,
+        help="log format as used by the logging module.",
+    )
+    add_option_ini(
+        "--log-date-format",
+        dest="log_date_format",
+        default=DEFAULT_LOG_DATE_FORMAT,
+        help="log date format as used by the logging module.",
+    )
+    parser.addini(
+        "log_cli",
+        default=False,
+        type="bool",
+        help='enable log display during test run (also known as "live logging").',
+    )
+    add_option_ini(
+        "--log-cli-level", dest="log_cli_level", default=None, help="cli logging level."
+    )
+    add_option_ini(
+        "--log-cli-format",
+        dest="log_cli_format",
+        default=None,
+        help="log format as used by the logging module.",
+    )
+    add_option_ini(
+        "--log-cli-date-format",
+        dest="log_cli_date_format",
+        default=None,
+        help="log date format as used by the logging module.",
+    )
+    add_option_ini(
+        "--log-file",
+        dest="log_file",
+        default=None,
+        help="path to a file when logging will be written to.",
+    )
+    add_option_ini(
+        "--log-file-level",
+        dest="log_file_level",
+        default=None,
+        help="log file logging level.",
+    )
+    add_option_ini(
+        "--log-file-format",
+        dest="log_file_format",
+        default=DEFAULT_LOG_FORMAT,
+        help="log format as used by the logging module.",
+    )
+    add_option_ini(
+        "--log-file-date-format",
+        dest="log_file_date_format",
+        default=DEFAULT_LOG_DATE_FORMAT,
+        help="log date format as used by the logging module.",
+    )
+
+
+@contextmanager
+def catching_logs(handler, formatter=None, level=None):
+    """Context manager that prepares the whole logging machinery properly."""
+    root_logger = logging.getLogger()
+
+    if formatter is not None:
+        handler.setFormatter(formatter)
+    if level is not None:
+        handler.setLevel(level)
+
+    # Adding the same handler twice would confuse logging system.
+    # Just don't do that.
+    add_new_handler = handler not in root_logger.handlers
+
+    if add_new_handler:
+        root_logger.addHandler(handler)
+    if level is not None:
+        orig_level = root_logger.level
+        root_logger.setLevel(min(orig_level, level))
+    try:
+        yield handler
+    finally:
+        if level is not None:
+            root_logger.setLevel(orig_level)
+        if add_new_handler:
+            root_logger.removeHandler(handler)
+
+
+class LogCaptureHandler(logging.StreamHandler):
+    """A logging handler that stores log records and the log text."""
+
+    def __init__(self):
+        """Creates a new log handler."""
+        logging.StreamHandler.__init__(self, py.io.TextIO())
+        self.records = []
+
+    def emit(self, record):
+        """Keep the log records in a list in addition to the log text."""
+        self.records.append(record)
+        logging.StreamHandler.emit(self, record)
+
+    def reset(self):
+        self.records = []
+        self.stream = py.io.TextIO()
+
+
+class LogCaptureFixture(object):
+    """Provides access and control of log capturing."""
+
+    def __init__(self, item):
+        """Creates a new funcarg."""
+        self._item = item
+        self._initial_log_levels = {}  # type: Dict[str, int] # dict of log name -> log level
+
+    def _finalize(self):
+        """Finalizes the fixture.
+
+        This restores the log levels changed by :meth:`set_level`.
+        """
+        # restore log levels
+        for logger_name, level in self._initial_log_levels.items():
+            logger = logging.getLogger(logger_name)
+            logger.setLevel(level)
+
+    @property
+    def handler(self):
+        """
+        :rtype: LogCaptureHandler
+        """
+        return self._item.catch_log_handler
+
+    def get_records(self, when):
+        """
+        Get the logging records for one of the possible test phases.
+
+        :param str when:
+            Which test phase to obtain the records from. Valid values are: "setup", "call" and "teardown".
+
+        :rtype: List[logging.LogRecord]
+        :return: the list of captured records at the given stage
+
+        .. versionadded:: 3.4
+        """
+        handler = self._item.catch_log_handlers.get(when)
+        if handler:
+            return handler.records
+        else:
+            return []
+
+    @property
+    def text(self):
+        """Returns the log text."""
+        return self.handler.stream.getvalue()
+
+    @property
+    def records(self):
+        """Returns the list of log records."""
+        return self.handler.records
+
+    @property
+    def record_tuples(self):
+        """Returns a list of a striped down version of log records intended
+        for use in assertion comparison.
+
+        The format of the tuple is:
+
+            (logger_name, log_level, message)
+        """
+        return [(r.name, r.levelno, r.getMessage()) for r in self.records]
+
+    @property
+    def messages(self):
+        """Returns a list of format-interpolated log messages.
+
+        Unlike 'records', which contains the format string and parameters for interpolation, log messages in this list
+        are all interpolated.
+        Unlike 'text', which contains the output from the handler, log messages in this list are unadorned with
+        levels, timestamps, etc, making exact comparisions more reliable.
+
+        Note that traceback or stack info (from :func:`logging.exception` or the `exc_info` or `stack_info` arguments
+        to the logging functions) is not included, as this is added by the formatter in the handler.
+
+        .. versionadded:: 3.7
+        """
+        return [r.getMessage() for r in self.records]
+
+    def clear(self):
+        """Reset the list of log records and the captured log text."""
+        self.handler.reset()
+
+    def set_level(self, level, logger=None):
+        """Sets the level for capturing of logs. The level will be restored to its previous value at the end of
+        the test.
+
+        :param int level: the logger to level.
+        :param str logger: the logger to update the level. If not given, the root logger level is updated.
+
+        .. versionchanged:: 3.4
+            The levels of the loggers changed by this function will be restored to their initial values at the
+            end of the test.
+        """
+        logger_name = logger
+        logger = logging.getLogger(logger_name)
+        # save the original log-level to restore it during teardown
+        self._initial_log_levels.setdefault(logger_name, logger.level)
+        logger.setLevel(level)
+
+    @contextmanager
+    def at_level(self, level, logger=None):
+        """Context manager that sets the level for capturing of logs. After the end of the 'with' statement the
+        level is restored to its original value.
+
+        :param int level: the logger to level.
+        :param str logger: the logger to update the level. If not given, the root logger level is updated.
+        """
+        logger = logging.getLogger(logger)
+        orig_level = logger.level
+        logger.setLevel(level)
+        try:
+            yield
+        finally:
+            logger.setLevel(orig_level)
+
+
+@pytest.fixture
+def caplog(request):
+    """Access and control log capturing.
+
+    Captured logs are available through the following methods::
+
+    * caplog.text            -> string containing formatted log output
+    * caplog.records         -> list of logging.LogRecord instances
+    * caplog.record_tuples   -> list of (logger_name, level, message) tuples
+    * caplog.clear()         -> clear captured records and formatted log output string
+    """
+    result = LogCaptureFixture(request.node)
+    yield result
+    result._finalize()
+
+
+def get_actual_log_level(config, *setting_names):
+    """Return the actual logging level."""
+
+    for setting_name in setting_names:
+        log_level = config.getoption(setting_name)
+        if log_level is None:
+            log_level = config.getini(setting_name)
+        if log_level:
+            break
+    else:
+        return
+
+    if isinstance(log_level, six.string_types):
+        log_level = log_level.upper()
+    try:
+        return int(getattr(logging, log_level, log_level))
+    except ValueError:
+        # Python logging does not recognise this as a logging level
+        raise pytest.UsageError(
+            "'{}' is not recognized as a logging level name for "
+            "'{}'. Please consider passing the "
+            "logging level num instead.".format(log_level, setting_name)
+        )
+
+
+def pytest_configure(config):
+    config.pluginmanager.register(LoggingPlugin(config), "logging-plugin")
+
+
+@contextmanager
+def _dummy_context_manager():
+    yield
+
+
+class LoggingPlugin(object):
+    """Attaches to the logging module and captures log messages for each test.
+    """
+
+    def __init__(self, config):
+        """Creates a new plugin to capture log messages.
+
+        The formatter can be safely shared across all handlers so
+        create a single one for the entire test session here.
+        """
+        self._config = config
+
+        # enable verbose output automatically if live logging is enabled
+        if self._log_cli_enabled() and not config.getoption("verbose"):
+            # sanity check: terminal reporter should not have been loaded at this point
+            assert self._config.pluginmanager.get_plugin("terminalreporter") is None
+            config.option.verbose = 1
+
+        self.print_logs = get_option_ini(config, "log_print")
+        self.formatter = logging.Formatter(
+            get_option_ini(config, "log_format"),
+            get_option_ini(config, "log_date_format"),
+        )
+        self.log_level = get_actual_log_level(config, "log_level")
+
+        log_file = get_option_ini(config, "log_file")
+        if log_file:
+            self.log_file_level = get_actual_log_level(config, "log_file_level")
+
+            log_file_format = get_option_ini(config, "log_file_format", "log_format")
+            log_file_date_format = get_option_ini(
+                config, "log_file_date_format", "log_date_format"
+            )
+            # Each pytest runtests session will write to a clean logfile
+            self.log_file_handler = logging.FileHandler(
+                log_file, mode="w", encoding="UTF-8"
+            )
+            log_file_formatter = logging.Formatter(
+                log_file_format, datefmt=log_file_date_format
+            )
+            self.log_file_handler.setFormatter(log_file_formatter)
+        else:
+            self.log_file_handler = None
+
+        # initialized during pytest_runtestloop
+        self.log_cli_handler = None
+
+    def _log_cli_enabled(self):
+        """Return True if log_cli should be considered enabled, either explicitly
+        or because --log-cli-level was given in the command-line.
+        """
+        return self._config.getoption(
+            "--log-cli-level"
+        ) is not None or self._config.getini("log_cli")
+
+    @contextmanager
+    def _runtest_for(self, item, when):
+        """Implements the internals of pytest_runtest_xxx() hook."""
+        with catching_logs(
+            LogCaptureHandler(), formatter=self.formatter, level=self.log_level
+        ) as log_handler:
+            if self.log_cli_handler:
+                self.log_cli_handler.set_when(when)
+
+            if item is None:
+                yield  # run the test
+                return
+
+            if not hasattr(item, "catch_log_handlers"):
+                item.catch_log_handlers = {}
+            item.catch_log_handlers[when] = log_handler
+            item.catch_log_handler = log_handler
+            try:
+                yield  # run test
+            finally:
+                del item.catch_log_handler
+                if when == "teardown":
+                    del item.catch_log_handlers
+
+            if self.print_logs:
+                # Add a captured log section to the report.
+                log = log_handler.stream.getvalue().strip()
+                item.add_report_section(when, "log", log)
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_setup(self, item):
+        with self._runtest_for(item, "setup"):
+            yield
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_call(self, item):
+        with self._runtest_for(item, "call"):
+            yield
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_teardown(self, item):
+        with self._runtest_for(item, "teardown"):
+            yield
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_logstart(self):
+        if self.log_cli_handler:
+            self.log_cli_handler.reset()
+        with self._runtest_for(None, "start"):
+            yield
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_logfinish(self):
+        with self._runtest_for(None, "finish"):
+            yield
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtestloop(self, session):
+        """Runs all collected test items."""
+        self._setup_cli_logging()
+        with self.live_logs_context:
+            if self.log_file_handler is not None:
+                with closing(self.log_file_handler):
+                    with catching_logs(
+                        self.log_file_handler, level=self.log_file_level
+                    ):
+                        yield  # run all the tests
+            else:
+                yield  # run all the tests
+
+    def _setup_cli_logging(self):
+        """Sets up the handler and logger for the Live Logs feature, if enabled.
+
+        This must be done right before starting the loop so we can access the terminal reporter plugin.
+        """
+        terminal_reporter = self._config.pluginmanager.get_plugin("terminalreporter")
+        if self._log_cli_enabled() and terminal_reporter is not None:
+            capture_manager = self._config.pluginmanager.get_plugin("capturemanager")
+            log_cli_handler = _LiveLoggingStreamHandler(
+                terminal_reporter, capture_manager
+            )
+            log_cli_format = get_option_ini(
+                self._config, "log_cli_format", "log_format"
+            )
+            log_cli_date_format = get_option_ini(
+                self._config, "log_cli_date_format", "log_date_format"
+            )
+            if (
+                self._config.option.color != "no"
+                and ColoredLevelFormatter.LEVELNAME_FMT_REGEX.search(log_cli_format)
+            ):
+                log_cli_formatter = ColoredLevelFormatter(
+                    create_terminal_writer(self._config),
+                    log_cli_format,
+                    datefmt=log_cli_date_format,
+                )
+            else:
+                log_cli_formatter = logging.Formatter(
+                    log_cli_format, datefmt=log_cli_date_format
+                )
+            log_cli_level = get_actual_log_level(
+                self._config, "log_cli_level", "log_level"
+            )
+            self.log_cli_handler = log_cli_handler
+            self.live_logs_context = catching_logs(
+                log_cli_handler, formatter=log_cli_formatter, level=log_cli_level
+            )
+        else:
+            self.live_logs_context = _dummy_context_manager()
+
+
+class _LiveLoggingStreamHandler(logging.StreamHandler):
+    """
+    Custom StreamHandler used by the live logging feature: it will write a newline before the first log message
+    in each test.
+
+    During live logging we must also explicitly disable stdout/stderr capturing otherwise it will get captured
+    and won't appear in the terminal.
+    """
+
+    def __init__(self, terminal_reporter, capture_manager):
+        """
+        :param _pytest.terminal.TerminalReporter terminal_reporter:
+        :param _pytest.capture.CaptureManager capture_manager:
+        """
+        logging.StreamHandler.__init__(self, stream=terminal_reporter)
+        self.capture_manager = capture_manager
+        self.reset()
+        self.set_when(None)
+        self._test_outcome_written = False
+
+    def reset(self):
+        """Reset the handler; should be called before the start of each test"""
+        self._first_record_emitted = False
+
+    def set_when(self, when):
+        """Prepares for the given test phase (setup/call/teardown)"""
+        self._when = when
+        self._section_name_shown = False
+        if when == "start":
+            self._test_outcome_written = False
+
+    def emit(self, record):
+        if self.capture_manager is not None:
+            self.capture_manager.suspend_global_capture()
+        try:
+            if not self._first_record_emitted:
+                self.stream.write("\n")
+                self._first_record_emitted = True
+            elif self._when in ("teardown", "finish"):
+                if not self._test_outcome_written:
+                    self._test_outcome_written = True
+                    self.stream.write("\n")
+            if not self._section_name_shown and self._when:
+                self.stream.section("live log " + self._when, sep="-", bold=True)
+                self._section_name_shown = True
+            logging.StreamHandler.emit(self, record)
+        finally:
+            if self.capture_manager is not None:
+                self.capture_manager.resume_global_capture()

src/_pytest/main.py

@@ -0,0 +1,660 @@
+""" core implementation of testing process: init, session, runtest loop. """
+from __future__ import absolute_import, division, print_function
+
+import contextlib
+import functools
+import os
+import pkgutil
+import six
+import sys
+
+import _pytest
+from _pytest import nodes
+import _pytest._code
+import py
+
+from _pytest.config import directory_arg, UsageError, hookimpl
+from _pytest.outcomes import exit
+from _pytest.runner import collect_one_node
+
+
+# exitcodes for the command line
+EXIT_OK = 0
+EXIT_TESTSFAILED = 1
+EXIT_INTERRUPTED = 2
+EXIT_INTERNALERROR = 3
+EXIT_USAGEERROR = 4
+EXIT_NOTESTSCOLLECTED = 5
+
+
+def pytest_addoption(parser):
+    parser.addini(
+        "norecursedirs",
+        "directory patterns to avoid for recursion",
+        type="args",
+        default=[".*", "build", "dist", "CVS", "_darcs", "{arch}", "*.egg", "venv"],
+    )
+    parser.addini(
+        "testpaths",
+        "directories to search for tests when no files or directories are given in the "
+        "command line.",
+        type="args",
+        default=[],
+    )
+    # parser.addini("dirpatterns",
+    #    "patterns specifying possible locations of test files",
+    #    type="linelist", default=["**/test_*.txt",
+    #            "**/test_*.py", "**/*_test.py"]
+    # )
+    group = parser.getgroup("general", "running and selection options")
+    group._addoption(
+        "-x",
+        "--exitfirst",
+        action="store_const",
+        dest="maxfail",
+        const=1,
+        help="exit instantly on first error or failed test.",
+    ),
+    group._addoption(
+        "--maxfail",
+        metavar="num",
+        action="store",
+        type=int,
+        dest="maxfail",
+        default=0,
+        help="exit after first num failures or errors.",
+    )
+    group._addoption(
+        "--strict",
+        action="store_true",
+        help="marks not registered in configuration file raise errors.",
+    )
+    group._addoption(
+        "-c",
+        metavar="file",
+        type=str,
+        dest="inifilename",
+        help="load configuration from `file` instead of trying to locate one of the implicit "
+        "configuration files.",
+    )
+    group._addoption(
+        "--continue-on-collection-errors",
+        action="store_true",
+        default=False,
+        dest="continue_on_collection_errors",
+        help="Force test execution even if collection errors occur.",
+    )
+    group._addoption(
+        "--rootdir",
+        action="store",
+        dest="rootdir",
+        help="Define root directory for tests. Can be relative path: 'root_dir', './root_dir', "
+        "'root_dir/another_dir/'; absolute path: '/home/user/root_dir'; path with variables: "
+        "'$HOME/root_dir'.",
+    )
+
+    group = parser.getgroup("collect", "collection")
+    group.addoption(
+        "--collectonly",
+        "--collect-only",
+        action="store_true",
+        help="only collect tests, don't execute them.",
+    ),
+    group.addoption(
+        "--pyargs",
+        action="store_true",
+        help="try to interpret all arguments as python packages.",
+    )
+    group.addoption(
+        "--ignore",
+        action="append",
+        metavar="path",
+        help="ignore path during collection (multi-allowed).",
+    )
+    group.addoption(
+        "--deselect",
+        action="append",
+        metavar="nodeid_prefix",
+        help="deselect item during collection (multi-allowed).",
+    )
+    # when changing this to --conf-cut-dir, config.py Conftest.setinitial
+    # needs upgrading as well
+    group.addoption(
+        "--confcutdir",
+        dest="confcutdir",
+        default=None,
+        metavar="dir",
+        type=functools.partial(directory_arg, optname="--confcutdir"),
+        help="only load conftest.py's relative to specified dir.",
+    )
+    group.addoption(
+        "--noconftest",
+        action="store_true",
+        dest="noconftest",
+        default=False,
+        help="Don't load any conftest.py files.",
+    )
+    group.addoption(
+        "--keepduplicates",
+        "--keep-duplicates",
+        action="store_true",
+        dest="keepduplicates",
+        default=False,
+        help="Keep duplicate tests.",
+    )
+    group.addoption(
+        "--collect-in-virtualenv",
+        action="store_true",
+        dest="collect_in_virtualenv",
+        default=False,
+        help="Don't ignore tests in a local virtualenv directory",
+    )
+
+    group = parser.getgroup("debugconfig", "test session debugging and configuration")
+    group.addoption(
+        "--basetemp",
+        dest="basetemp",
+        default=None,
+        metavar="dir",
+        help="base temporary directory for this test run.",
+    )
+
+
+def pytest_configure(config):
+    __import__("pytest").config = config  # compatibility
+
+
+def wrap_session(config, doit):
+    """Skeleton command line program"""
+    session = Session(config)
+    session.exitstatus = EXIT_OK
+    initstate = 0
+    try:
+        try:
+            config._do_configure()
+            initstate = 1
+            config.hook.pytest_sessionstart(session=session)
+            initstate = 2
+            session.exitstatus = doit(config, session) or 0
+        except UsageError:
+            raise
+        except Failed:
+            session.exitstatus = EXIT_TESTSFAILED
+        except KeyboardInterrupt:
+            excinfo = _pytest._code.ExceptionInfo()
+            if initstate < 2 and isinstance(excinfo.value, exit.Exception):
+                sys.stderr.write("{}: {}\n".format(excinfo.typename, excinfo.value.msg))
+            config.hook.pytest_keyboard_interrupt(excinfo=excinfo)
+            session.exitstatus = EXIT_INTERRUPTED
+        except:  # noqa
+            excinfo = _pytest._code.ExceptionInfo()
+            config.notify_exception(excinfo, config.option)
+            session.exitstatus = EXIT_INTERNALERROR
+            if excinfo.errisinstance(SystemExit):
+                sys.stderr.write("mainloop: caught Spurious SystemExit!\n")
+
+    finally:
+        excinfo = None  # Explicitly break reference cycle.
+        session.startdir.chdir()
+        if initstate >= 2:
+            config.hook.pytest_sessionfinish(
+                session=session, exitstatus=session.exitstatus
+            )
+        config._ensure_unconfigure()
+    return session.exitstatus
+
+
+def pytest_cmdline_main(config):
+    return wrap_session(config, _main)
+
+
+def _main(config, session):
+    """ default command line protocol for initialization, session,
+    running tests and reporting. """
+    config.hook.pytest_collection(session=session)
+    config.hook.pytest_runtestloop(session=session)
+
+    if session.testsfailed:
+        return EXIT_TESTSFAILED
+    elif session.testscollected == 0:
+        return EXIT_NOTESTSCOLLECTED
+
+
+def pytest_collection(session):
+    return session.perform_collect()
+
+
+def pytest_runtestloop(session):
+    if session.testsfailed and not session.config.option.continue_on_collection_errors:
+        raise session.Interrupted("%d errors during collection" % session.testsfailed)
+
+    if session.config.option.collectonly:
+        return True
+
+    for i, item in enumerate(session.items):
+        nextitem = session.items[i + 1] if i + 1 < len(session.items) else None
+        item.config.hook.pytest_runtest_protocol(item=item, nextitem=nextitem)
+        if session.shouldfail:
+            raise session.Failed(session.shouldfail)
+        if session.shouldstop:
+            raise session.Interrupted(session.shouldstop)
+    return True
+
+
+def _in_venv(path):
+    """Attempts to detect if ``path`` is the root of a Virtual Environment by
+    checking for the existence of the appropriate activate script"""
+    bindir = path.join("Scripts" if sys.platform.startswith("win") else "bin")
+    if not bindir.isdir():
+        return False
+    activates = (
+        "activate",
+        "activate.csh",
+        "activate.fish",
+        "Activate",
+        "Activate.bat",
+        "Activate.ps1",
+    )
+    return any([fname.basename in activates for fname in bindir.listdir()])
+
+
+def pytest_ignore_collect(path, config):
+    ignore_paths = config._getconftest_pathlist("collect_ignore", path=path.dirpath())
+    ignore_paths = ignore_paths or []
+    excludeopt = config.getoption("ignore")
+    if excludeopt:
+        ignore_paths.extend([py.path.local(x) for x in excludeopt])
+
+    if py.path.local(path) in ignore_paths:
+        return True
+
+    allow_in_venv = config.getoption("collect_in_virtualenv")
+    if _in_venv(path) and not allow_in_venv:
+        return True
+
+    # Skip duplicate paths.
+    keepduplicates = config.getoption("keepduplicates")
+    duplicate_paths = config.pluginmanager._duplicatepaths
+    if not keepduplicates:
+        if path in duplicate_paths:
+            return True
+        else:
+            duplicate_paths.add(path)
+
+    return False
+
+
+def pytest_collection_modifyitems(items, config):
+    deselect_prefixes = tuple(config.getoption("deselect") or [])
+    if not deselect_prefixes:
+        return
+
+    remaining = []
+    deselected = []
+    for colitem in items:
+        if colitem.nodeid.startswith(deselect_prefixes):
+            deselected.append(colitem)
+        else:
+            remaining.append(colitem)
+
+    if deselected:
+        config.hook.pytest_deselected(items=deselected)
+        items[:] = remaining
+
+
+@contextlib.contextmanager
+def _patched_find_module():
+    """Patch bug in pkgutil.ImpImporter.find_module
+
+    When using pkgutil.find_loader on python<3.4 it removes symlinks
+    from the path due to a call to os.path.realpath. This is not consistent
+    with actually doing the import (in these versions, pkgutil and __import__
+    did not share the same underlying code). This can break conftest
+    discovery for pytest where symlinks are involved.
+
+    The only supported python<3.4 by pytest is python 2.7.
+    """
+    if six.PY2:  # python 3.4+ uses importlib instead
+
+        def find_module_patched(self, fullname, path=None):
+            # Note: we ignore 'path' argument since it is only used via meta_path
+            subname = fullname.split(".")[-1]
+            if subname != fullname and self.path is None:
+                return None
+            if self.path is None:
+                path = None
+            else:
+                # original: path = [os.path.realpath(self.path)]
+                path = [self.path]
+            try:
+                file, filename, etc = pkgutil.imp.find_module(subname, path)
+            except ImportError:
+                return None
+            return pkgutil.ImpLoader(fullname, file, filename, etc)
+
+        old_find_module = pkgutil.ImpImporter.find_module
+        pkgutil.ImpImporter.find_module = find_module_patched
+        try:
+            yield
+        finally:
+            pkgutil.ImpImporter.find_module = old_find_module
+    else:
+        yield
+
+
+class FSHookProxy(object):
+    def __init__(self, fspath, pm, remove_mods):
+        self.fspath = fspath
+        self.pm = pm
+        self.remove_mods = remove_mods
+
+    def __getattr__(self, name):
+        x = self.pm.subset_hook_caller(name, remove_plugins=self.remove_mods)
+        self.__dict__[name] = x
+        return x
+
+
+class NoMatch(Exception):
+    """ raised if matching cannot locate a matching names. """
+
+
+class Interrupted(KeyboardInterrupt):
+    """ signals an interrupted test run. """
+
+    __module__ = "builtins"  # for py3
+
+
+class Failed(Exception):
+    """ signals a stop as failed test run. """
+
+
+class Session(nodes.FSCollector):
+    Interrupted = Interrupted
+    Failed = Failed
+
+    def __init__(self, config):
+        nodes.FSCollector.__init__(
+            self, config.rootdir, parent=None, config=config, session=self, nodeid=""
+        )
+        self.testsfailed = 0
+        self.testscollected = 0
+        self.shouldstop = False
+        self.shouldfail = False
+        self.trace = config.trace.root.get("collection")
+        self._norecursepatterns = config.getini("norecursedirs")
+        self.startdir = py.path.local()
+        # Keep track of any collected nodes in here, so we don't duplicate fixtures
+        self._node_cache = {}
+
+        self.config.pluginmanager.register(self, name="session")
+
+    @hookimpl(tryfirst=True)
+    def pytest_collectstart(self):
+        if self.shouldfail:
+            raise self.Failed(self.shouldfail)
+        if self.shouldstop:
+            raise self.Interrupted(self.shouldstop)
+
+    @hookimpl(tryfirst=True)
+    def pytest_runtest_logreport(self, report):
+        if report.failed and not hasattr(report, "wasxfail"):
+            self.testsfailed += 1
+            maxfail = self.config.getvalue("maxfail")
+            if maxfail and self.testsfailed >= maxfail:
+                self.shouldfail = "stopping after %d failures" % (self.testsfailed)
+
+    pytest_collectreport = pytest_runtest_logreport
+
+    def isinitpath(self, path):
+        return path in self._initialpaths
+
+    def gethookproxy(self, fspath):
+        # check if we have the common case of running
+        # hooks with all conftest.py files
+        pm = self.config.pluginmanager
+        my_conftestmodules = pm._getconftestmodules(fspath)
+        remove_mods = pm._conftest_plugins.difference(my_conftestmodules)
+        if remove_mods:
+            # one or more conftests are not in use at this fspath
+            proxy = FSHookProxy(fspath, pm, remove_mods)
+        else:
+            # all plugis are active for this fspath
+            proxy = self.config.hook
+        return proxy
+
+    def perform_collect(self, args=None, genitems=True):
+        hook = self.config.hook
+        try:
+            items = self._perform_collect(args, genitems)
+            self.config.pluginmanager.check_pending()
+            hook.pytest_collection_modifyitems(
+                session=self, config=self.config, items=items
+            )
+        finally:
+            hook.pytest_collection_finish(session=self)
+        self.testscollected = len(items)
+        return items
+
+    def _perform_collect(self, args, genitems):
+        if args is None:
+            args = self.config.args
+        self.trace("perform_collect", self, args)
+        self.trace.root.indent += 1
+        self._notfound = []
+        self._initialpaths = set()
+        self._initialparts = []
+        self.items = items = []
+        for arg in args:
+            parts = self._parsearg(arg)
+            self._initialparts.append(parts)
+            self._initialpaths.add(parts[0])
+        rep = collect_one_node(self)
+        self.ihook.pytest_collectreport(report=rep)
+        self.trace.root.indent -= 1
+        if self._notfound:
+            errors = []
+            for arg, exc in self._notfound:
+                line = "(no name %r in any of %r)" % (arg, exc.args[0])
+                errors.append("not found: %s\n%s" % (arg, line))
+                # XXX: test this
+            raise UsageError(*errors)
+        if not genitems:
+            return rep.result
+        else:
+            if rep.passed:
+                for node in rep.result:
+                    self.items.extend(self.genitems(node))
+            return items
+
+    def collect(self):
+        for parts in self._initialparts:
+            arg = "::".join(map(str, parts))
+            self.trace("processing argument", arg)
+            self.trace.root.indent += 1
+            try:
+                for x in self._collect(arg):
+                    yield x
+            except NoMatch:
+                # we are inside a make_report hook so
+                # we cannot directly pass through the exception
+                self._notfound.append((arg, sys.exc_info()[1]))
+
+            self.trace.root.indent -= 1
+
+    def _collect(self, arg):
+        names = self._parsearg(arg)
+        argpath = names.pop(0)
+        paths = []
+
+        root = self
+        # Start with a Session root, and delve to argpath item (dir or file)
+        # and stack all Packages found on the way.
+        # No point in finding packages when collecting doctests
+        if not self.config.option.doctestmodules:
+            for parent in argpath.parts():
+                pm = self.config.pluginmanager
+                if pm._confcutdir and pm._confcutdir.relto(parent):
+                    continue
+
+                if parent.isdir():
+                    pkginit = parent.join("__init__.py")
+                    if pkginit.isfile():
+                        if pkginit in self._node_cache:
+                            root = self._node_cache[pkginit]
+                        else:
+                            col = root._collectfile(pkginit)
+                            if col:
+                                root = col[0]
+                                self._node_cache[root.fspath] = root
+
+        # If it's a directory argument, recurse and look for any Subpackages.
+        # Let the Package collector deal with subnodes, don't collect here.
+        if argpath.check(dir=1):
+            assert not names, "invalid arg %r" % (arg,)
+            for path in argpath.visit(
+                fil=lambda x: x.check(file=1), rec=self._recurse, bf=True, sort=True
+            ):
+                pkginit = path.dirpath().join("__init__.py")
+                if pkginit.exists() and not any(x in pkginit.parts() for x in paths):
+                    for x in root._collectfile(pkginit):
+                        yield x
+                        paths.append(x.fspath.dirpath())
+
+                if not any(x in path.parts() for x in paths):
+                    for x in root._collectfile(path):
+                        if (type(x), x.fspath) in self._node_cache:
+                            yield self._node_cache[(type(x), x.fspath)]
+                        else:
+                            yield x
+                            self._node_cache[(type(x), x.fspath)] = x
+        else:
+            assert argpath.check(file=1)
+
+            if argpath in self._node_cache:
+                col = self._node_cache[argpath]
+            else:
+                col = root._collectfile(argpath)
+                if col:
+                    self._node_cache[argpath] = col
+            for y in self.matchnodes(col, names):
+                yield y
+
+    def _collectfile(self, path):
+        ihook = self.gethookproxy(path)
+        if not self.isinitpath(path):
+            if ihook.pytest_ignore_collect(path=path, config=self.config):
+                return ()
+        return ihook.pytest_collect_file(path=path, parent=self)
+
+    def _recurse(self, path):
+        ihook = self.gethookproxy(path.dirpath())
+        if ihook.pytest_ignore_collect(path=path, config=self.config):
+            return
+        for pat in self._norecursepatterns:
+            if path.check(fnmatch=pat):
+                return False
+        ihook = self.gethookproxy(path)
+        ihook.pytest_collect_directory(path=path, parent=self)
+        return True
+
+    def _tryconvertpyarg(self, x):
+        """Convert a dotted module name to path.
+
+        """
+
+        try:
+            with _patched_find_module():
+                loader = pkgutil.find_loader(x)
+        except ImportError:
+            return x
+        if loader is None:
+            return x
+        # This method is sometimes invoked when AssertionRewritingHook, which
+        # does not define a get_filename method, is already in place:
+        try:
+            with _patched_find_module():
+                path = loader.get_filename(x)
+        except AttributeError:
+            # Retrieve path from AssertionRewritingHook:
+            path = loader.modules[x][0].co_filename
+        if loader.is_package(x):
+            path = os.path.dirname(path)
+        return path
+
+    def _parsearg(self, arg):
+        """ return (fspath, names) tuple after checking the file exists. """
+        parts = str(arg).split("::")
+        if self.config.option.pyargs:
+            parts[0] = self._tryconvertpyarg(parts[0])
+        relpath = parts[0].replace("/", os.sep)
+        path = self.config.invocation_dir.join(relpath, abs=True)
+        if not path.check():
+            if self.config.option.pyargs:
+                raise UsageError(
+                    "file or package not found: " + arg + " (missing __init__.py?)"
+                )
+            else:
+                raise UsageError("file not found: " + arg)
+        parts[0] = path
+        return parts
+
+    def matchnodes(self, matching, names):
+        self.trace("matchnodes", matching, names)
+        self.trace.root.indent += 1
+        nodes = self._matchnodes(matching, names)
+        num = len(nodes)
+        self.trace("matchnodes finished -> ", num, "nodes")
+        self.trace.root.indent -= 1
+        if num == 0:
+            raise NoMatch(matching, names[:1])
+        return nodes
+
+    def _matchnodes(self, matching, names):
+        if not matching or not names:
+            return matching
+        name = names[0]
+        assert name
+        nextnames = names[1:]
+        resultnodes = []
+        for node in matching:
+            if isinstance(node, nodes.Item):
+                if not names:
+                    resultnodes.append(node)
+                continue
+            assert isinstance(node, nodes.Collector)
+            if node.nodeid in self._node_cache:
+                rep = self._node_cache[node.nodeid]
+            else:
+                rep = collect_one_node(node)
+                self._node_cache[node.nodeid] = rep
+            if rep.passed:
+                has_matched = False
+                for x in rep.result:
+                    # TODO: remove parametrized workaround once collection structure contains parametrization
+                    if x.name == name or x.name.split("[")[0] == name:
+                        resultnodes.extend(self.matchnodes([x], nextnames))
+                        has_matched = True
+                # XXX accept IDs that don't have "()" for class instances
+                if not has_matched and len(rep.result) == 1 and x.name == "()":
+                    nextnames.insert(0, name)
+                    resultnodes.extend(self.matchnodes([x], nextnames))
+            else:
+                # report collection failures here to avoid failing to run some test
+                # specified in the command line because the module could not be
+                # imported (#134)
+                node.ihook.pytest_collectreport(report=rep)
+        return resultnodes
+
+    def genitems(self, node):
+        self.trace("genitems", node)
+        if isinstance(node, nodes.Item):
+            node.ihook.pytest_itemcollected(item=node)
+            yield node
+        else:
+            assert isinstance(node, nodes.Collector)
+            rep = collect_one_node(node)
+            if rep.passed:
+                for subnode in rep.result:
+                    for x in self.genitems(subnode):
+                        yield x
+            node.ihook.pytest_collectreport(report=rep)

src/_pytest/mark/__init__.py

@@ -0,0 +1,174 @@
+""" generic mechanism for marking and selecting python functions. """
+from __future__ import absolute_import, division, print_function
+from _pytest.config import UsageError
+from .structures import (
+    ParameterSet,
+    EMPTY_PARAMETERSET_OPTION,
+    MARK_GEN,
+    Mark,
+    MarkInfo,
+    MarkDecorator,
+    MarkGenerator,
+    transfer_markers,
+    get_empty_parameterset_mark,
+)
+from .legacy import matchkeyword, matchmark
+
+__all__ = [
+    "Mark",
+    "MarkInfo",
+    "MarkDecorator",
+    "MarkGenerator",
+    "transfer_markers",
+    "get_empty_parameterset_mark",
+]
+
+
+class MarkerError(Exception):
+
+    """Error in use of a pytest marker/attribute."""
+
+
+def param(*values, **kw):
+    """Specify a parameter in `pytest.mark.parametrize`_ calls or
+    :ref:`parametrized fixtures <fixture-parametrize-marks>`.
+
+    .. code-block:: python
+
+        @pytest.mark.parametrize("test_input,expected", [
+            ("3+5", 8),
+            pytest.param("6*9", 42, marks=pytest.mark.xfail),
+        ])
+        def test_eval(test_input, expected):
+            assert eval(test_input) == expected
+
+    :param values: variable args of the values of the parameter set, in order.
+    :keyword marks: a single mark or a list of marks to be applied to this parameter set.
+    :keyword str id: the id to attribute to this parameter set.
+    """
+    return ParameterSet.param(*values, **kw)
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("general")
+    group._addoption(
+        "-k",
+        action="store",
+        dest="keyword",
+        default="",
+        metavar="EXPRESSION",
+        help="only run tests which match the given substring expression. "
+        "An expression is a python evaluatable expression "
+        "where all names are substring-matched against test names "
+        "and their parent classes. Example: -k 'test_method or test_"
+        "other' matches all test functions and classes whose name "
+        "contains 'test_method' or 'test_other', while -k 'not test_method' "
+        "matches those that don't contain 'test_method' in their names. "
+        "Additionally keywords are matched to classes and functions "
+        "containing extra names in their 'extra_keyword_matches' set, "
+        "as well as functions which have names assigned directly to them.",
+    )
+
+    group._addoption(
+        "-m",
+        action="store",
+        dest="markexpr",
+        default="",
+        metavar="MARKEXPR",
+        help="only run tests matching given mark expression.  "
+        "example: -m 'mark1 and not mark2'.",
+    )
+
+    group.addoption(
+        "--markers",
+        action="store_true",
+        help="show markers (builtin, plugin and per-project ones).",
+    )
+
+    parser.addini("markers", "markers for test functions", "linelist")
+    parser.addini(EMPTY_PARAMETERSET_OPTION, "default marker for empty parametersets")
+
+
+def pytest_cmdline_main(config):
+    import _pytest.config
+
+    if config.option.markers:
+        config._do_configure()
+        tw = _pytest.config.create_terminal_writer(config)
+        for line in config.getini("markers"):
+            parts = line.split(":", 1)
+            name = parts[0]
+            rest = parts[1] if len(parts) == 2 else ""
+            tw.write("@pytest.mark.%s:" % name, bold=True)
+            tw.line(rest)
+            tw.line()
+        config._ensure_unconfigure()
+        return 0
+
+
+pytest_cmdline_main.tryfirst = True
+
+
+def deselect_by_keyword(items, config):
+    keywordexpr = config.option.keyword.lstrip()
+    if keywordexpr.startswith("-"):
+        keywordexpr = "not " + keywordexpr[1:]
+    selectuntil = False
+    if keywordexpr[-1:] == ":":
+        selectuntil = True
+        keywordexpr = keywordexpr[:-1]
+
+    remaining = []
+    deselected = []
+    for colitem in items:
+        if keywordexpr and not matchkeyword(colitem, keywordexpr):
+            deselected.append(colitem)
+        else:
+            if selectuntil:
+                keywordexpr = None
+            remaining.append(colitem)
+
+    if deselected:
+        config.hook.pytest_deselected(items=deselected)
+        items[:] = remaining
+
+
+def deselect_by_mark(items, config):
+    matchexpr = config.option.markexpr
+    if not matchexpr:
+        return
+
+    remaining = []
+    deselected = []
+    for item in items:
+        if matchmark(item, matchexpr):
+            remaining.append(item)
+        else:
+            deselected.append(item)
+
+    if deselected:
+        config.hook.pytest_deselected(items=deselected)
+        items[:] = remaining
+
+
+def pytest_collection_modifyitems(items, config):
+    deselect_by_keyword(items, config)
+    deselect_by_mark(items, config)
+
+
+def pytest_configure(config):
+    config._old_mark_config = MARK_GEN._config
+    if config.option.strict:
+        MARK_GEN._config = config
+
+    empty_parameterset = config.getini(EMPTY_PARAMETERSET_OPTION)
+
+    if empty_parameterset not in ("skip", "xfail", None, ""):
+        raise UsageError(
+            "{!s} must be one of skip and xfail,"
+            " but it is {!r}".format(EMPTY_PARAMETERSET_OPTION, empty_parameterset)
+        )
+
+
+def pytest_unconfigure(config):
+    MARK_GEN._config = getattr(config, "_old_mark_config", None)

src/_pytest/mark/evaluate.py

@@ -0,0 +1,120 @@
+import os
+import six
+import sys
+import platform
+import traceback
+
+from ..outcomes import fail, TEST_OUTCOME
+
+
+def cached_eval(config, expr, d):
+    if not hasattr(config, "_evalcache"):
+        config._evalcache = {}
+    try:
+        return config._evalcache[expr]
+    except KeyError:
+        import _pytest._code
+
+        exprcode = _pytest._code.compile(expr, mode="eval")
+        config._evalcache[expr] = x = eval(exprcode, d)
+        return x
+
+
+class MarkEvaluator(object):
+    def __init__(self, item, name):
+        self.item = item
+        self._marks = None
+        self._mark = None
+        self._mark_name = name
+
+    def __bool__(self):
+        # dont cache here to prevent staleness
+        return bool(self._get_marks())
+
+    __nonzero__ = __bool__
+
+    def wasvalid(self):
+        return not hasattr(self, "exc")
+
+    def _get_marks(self):
+        return list(self.item.iter_markers(name=self._mark_name))
+
+    def invalidraise(self, exc):
+        raises = self.get("raises")
+        if not raises:
+            return
+        return not isinstance(exc, raises)
+
+    def istrue(self):
+        try:
+            return self._istrue()
+        except TEST_OUTCOME:
+            self.exc = sys.exc_info()
+            if isinstance(self.exc[1], SyntaxError):
+                msg = [" " * (self.exc[1].offset + 4) + "^"]
+                msg.append("SyntaxError: invalid syntax")
+            else:
+                msg = traceback.format_exception_only(*self.exc[:2])
+            fail(
+                "Error evaluating %r expression\n"
+                "    %s\n"
+                "%s" % (self._mark_name, self.expr, "\n".join(msg)),
+                pytrace=False,
+            )
+
+    def _getglobals(self):
+        d = {"os": os, "sys": sys, "platform": platform, "config": self.item.config}
+        if hasattr(self.item, "obj"):
+            d.update(self.item.obj.__globals__)
+        return d
+
+    def _istrue(self):
+        if hasattr(self, "result"):
+            return self.result
+        self._marks = self._get_marks()
+
+        if self._marks:
+            self.result = False
+            for mark in self._marks:
+                self._mark = mark
+                if "condition" in mark.kwargs:
+                    args = (mark.kwargs["condition"],)
+                else:
+                    args = mark.args
+
+                for expr in args:
+                    self.expr = expr
+                    if isinstance(expr, six.string_types):
+                        d = self._getglobals()
+                        result = cached_eval(self.item.config, expr, d)
+                    else:
+                        if "reason" not in mark.kwargs:
+                            # XXX better be checked at collection time
+                            msg = "you need to specify reason=STRING " "when using booleans as conditions."
+                            fail(msg)
+                        result = bool(expr)
+                    if result:
+                        self.result = True
+                        self.reason = mark.kwargs.get("reason", None)
+                        self.expr = expr
+                        return self.result
+
+                if not args:
+                    self.result = True
+                    self.reason = mark.kwargs.get("reason", None)
+                    return self.result
+        return False
+
+    def get(self, attr, default=None):
+        if self._mark is None:
+            return default
+        return self._mark.kwargs.get(attr, default)
+
+    def getexplanation(self):
+        expl = getattr(self, "reason", None) or self.get("reason", None)
+        if not expl:
+            if not hasattr(self, "expr"):
+                return ""
+            else:
+                return "condition: " + str(self.expr)
+        return expl

src/_pytest/mark/legacy.py

@@ -0,0 +1,97 @@
+"""
+this is a place where we put datastructures used by legacy apis
+we hope ot remove
+"""
+import attr
+import keyword
+
+from _pytest.config import UsageError
+
+
+@attr.s
+class MarkMapping(object):
+    """Provides a local mapping for markers where item access
+    resolves to True if the marker is present. """
+
+    own_mark_names = attr.ib()
+
+    @classmethod
+    def from_item(cls, item):
+        mark_names = {mark.name for mark in item.iter_markers()}
+        return cls(mark_names)
+
+    def __getitem__(self, name):
+        return name in self.own_mark_names
+
+
+class KeywordMapping(object):
+    """Provides a local mapping for keywords.
+    Given a list of names, map any substring of one of these names to True.
+    """
+
+    def __init__(self, names):
+        self._names = names
+
+    @classmethod
+    def from_item(cls, item):
+        mapped_names = set()
+
+        # Add the names of the current item and any parent items
+        import pytest
+
+        for item in item.listchain():
+            if not isinstance(item, pytest.Instance):
+                mapped_names.add(item.name)
+
+        # Add the names added as extra keywords to current or parent items
+        for name in item.listextrakeywords():
+            mapped_names.add(name)
+
+        # Add the names attached to the current function through direct assignment
+        if hasattr(item, "function"):
+            for name in item.function.__dict__:
+                mapped_names.add(name)
+
+        return cls(mapped_names)
+
+    def __getitem__(self, subname):
+        for name in self._names:
+            if subname in name:
+                return True
+        return False
+
+
+python_keywords_allowed_list = ["or", "and", "not"]
+
+
+def matchmark(colitem, markexpr):
+    """Tries to match on any marker names, attached to the given colitem."""
+    return eval(markexpr, {}, MarkMapping.from_item(colitem))
+
+
+def matchkeyword(colitem, keywordexpr):
+    """Tries to match given keyword expression to given collector item.
+
+    Will match on the name of colitem, including the names of its parents.
+    Only matches names of items which are either a :class:`Class` or a
+    :class:`Function`.
+    Additionally, matches on names in the 'extra_keyword_matches' set of
+    any item, as well as names directly assigned to test functions.
+    """
+    mapping = KeywordMapping.from_item(colitem)
+    if " " not in keywordexpr:
+        # special case to allow for simple "-k pass" and "-k 1.3"
+        return mapping[keywordexpr]
+    elif keywordexpr.startswith("not ") and " " not in keywordexpr[4:]:
+        return not mapping[keywordexpr[4:]]
+    for kwd in keywordexpr.split():
+        if keyword.iskeyword(kwd) and kwd not in python_keywords_allowed_list:
+            raise UsageError(
+                "Python keyword '{}' not accepted in expressions passed to '-k'".format(
+                    kwd
+                )
+            )
+    try:
+        return eval(keywordexpr, {}, mapping)
+    except SyntaxError:
+        raise UsageError("Wrong expression passed to '-k': {}".format(keywordexpr))

src/_pytest/mark/structures.py

@@ -0,0 +1,442 @@
+import inspect
+import warnings
+from collections import namedtuple
+from functools import reduce
+from operator import attrgetter
+
+import attr
+
+from ..deprecated import MARK_PARAMETERSET_UNPACKING, MARK_INFO_ATTRIBUTE
+from ..compat import NOTSET, getfslineno, MappingMixin
+from six.moves import map
+
+
+EMPTY_PARAMETERSET_OPTION = "empty_parameter_set_mark"
+
+
+def alias(name, warning=None):
+    getter = attrgetter(name)
+
+    def warned(self):
+        warnings.warn(warning, stacklevel=2)
+        return getter(self)
+
+    return property(getter if warning is None else warned, doc="alias for " + name)
+
+
+def istestfunc(func):
+    return (
+        hasattr(func, "__call__")
+        and getattr(func, "__name__", "<lambda>") != "<lambda>"
+    )
+
+
+def get_empty_parameterset_mark(config, argnames, func):
+    requested_mark = config.getini(EMPTY_PARAMETERSET_OPTION)
+    if requested_mark in ("", None, "skip"):
+        mark = MARK_GEN.skip
+    elif requested_mark == "xfail":
+        mark = MARK_GEN.xfail(run=False)
+    else:
+        raise LookupError(requested_mark)
+    fs, lineno = getfslineno(func)
+    reason = "got empty parameter set %r, function %s at %s:%d" % (
+        argnames,
+        func.__name__,
+        fs,
+        lineno,
+    )
+    return mark(reason=reason)
+
+
+class ParameterSet(namedtuple("ParameterSet", "values, marks, id")):
+    @classmethod
+    def param(cls, *values, **kw):
+        marks = kw.pop("marks", ())
+        if isinstance(marks, MarkDecorator):
+            marks = (marks,)
+        else:
+            assert isinstance(marks, (tuple, list, set))
+
+        def param_extract_id(id=None):
+            return id
+
+        id_ = param_extract_id(**kw)
+        return cls(values, marks, id_)
+
+    @classmethod
+    def extract_from(cls, parameterset, legacy_force_tuple=False):
+        """
+        :param parameterset:
+            a legacy style parameterset that may or may not be a tuple,
+            and may or may not be wrapped into a mess of mark objects
+
+        :param legacy_force_tuple:
+            enforce tuple wrapping so single argument tuple values
+            don't get decomposed and break tests
+
+        """
+
+        if isinstance(parameterset, cls):
+            return parameterset
+        if not isinstance(parameterset, MarkDecorator) and legacy_force_tuple:
+            return cls.param(parameterset)
+
+        newmarks = []
+        argval = parameterset
+        while isinstance(argval, MarkDecorator):
+            newmarks.append(
+                MarkDecorator(Mark(argval.markname, argval.args[:-1], argval.kwargs))
+            )
+            argval = argval.args[-1]
+        assert not isinstance(argval, ParameterSet)
+        if legacy_force_tuple:
+            argval = (argval,)
+
+        if newmarks:
+            warnings.warn(MARK_PARAMETERSET_UNPACKING)
+
+        return cls(argval, marks=newmarks, id=None)
+
+    @classmethod
+    def _for_parametrize(cls, argnames, argvalues, func, config):
+        if not isinstance(argnames, (tuple, list)):
+            argnames = [x.strip() for x in argnames.split(",") if x.strip()]
+            force_tuple = len(argnames) == 1
+        else:
+            force_tuple = False
+        parameters = [
+            ParameterSet.extract_from(x, legacy_force_tuple=force_tuple)
+            for x in argvalues
+        ]
+        del argvalues
+
+        if not parameters:
+            mark = get_empty_parameterset_mark(config, argnames, func)
+            parameters.append(
+                ParameterSet(values=(NOTSET,) * len(argnames), marks=[mark], id=None)
+            )
+        return argnames, parameters
+
+
+@attr.s(frozen=True)
+class Mark(object):
+    #: name of the mark
+    name = attr.ib(type=str)
+    #: positional arguments of the mark decorator
+    args = attr.ib(type="List[object]")
+    #: keyword arguments of the mark decorator
+    kwargs = attr.ib(type="Dict[str, object]")
+
+    def combined_with(self, other):
+        """
+        :param other: the mark to combine with
+        :type other: Mark
+        :rtype: Mark
+
+        combines by appending aargs and merging the mappings
+        """
+        assert self.name == other.name
+        return Mark(
+            self.name, self.args + other.args, dict(self.kwargs, **other.kwargs)
+        )
+
+
+@attr.s
+class MarkDecorator(object):
+    """ A decorator for test functions and test classes.  When applied
+    it will create :class:`MarkInfo` objects which may be
+    :ref:`retrieved by hooks as item keywords <excontrolskip>`.
+    MarkDecorator instances are often created like this::
+
+        mark1 = pytest.mark.NAME              # simple MarkDecorator
+        mark2 = pytest.mark.NAME(name1=value) # parametrized MarkDecorator
+
+    and can then be applied as decorators to test functions::
+
+        @mark2
+        def test_function():
+            pass
+
+    When a MarkDecorator instance is called it does the following:
+      1. If called with a single class as its only positional argument and no
+         additional keyword arguments, it attaches itself to the class so it
+         gets applied automatically to all test cases found in that class.
+      2. If called with a single function as its only positional argument and
+         no additional keyword arguments, it attaches a MarkInfo object to the
+         function, containing all the arguments already stored internally in
+         the MarkDecorator.
+      3. When called in any other case, it performs a 'fake construction' call,
+         i.e. it returns a new MarkDecorator instance with the original
+         MarkDecorator's content updated with the arguments passed to this
+         call.
+
+    Note: The rules above prevent MarkDecorator objects from storing only a
+    single function or class reference as their positional argument with no
+    additional keyword or positional arguments.
+
+    """
+
+    mark = attr.ib(validator=attr.validators.instance_of(Mark))
+
+    name = alias("mark.name")
+    args = alias("mark.args")
+    kwargs = alias("mark.kwargs")
+
+    @property
+    def markname(self):
+        return self.name  # for backward-compat (2.4.1 had this attr)
+
+    def __eq__(self, other):
+        return self.mark == other.mark if isinstance(other, MarkDecorator) else False
+
+    def __repr__(self):
+        return "<MarkDecorator %r>" % (self.mark,)
+
+    def with_args(self, *args, **kwargs):
+        """ return a MarkDecorator with extra arguments added
+
+        unlike call this can be used even if the sole argument is a callable/class
+
+        :return: MarkDecorator
+        """
+
+        mark = Mark(self.name, args, kwargs)
+        return self.__class__(self.mark.combined_with(mark))
+
+    def __call__(self, *args, **kwargs):
+        """ if passed a single callable argument: decorate it with mark info.
+            otherwise add *args/**kwargs in-place to mark information. """
+        if args and not kwargs:
+            func = args[0]
+            is_class = inspect.isclass(func)
+            if len(args) == 1 and (istestfunc(func) or is_class):
+                if is_class:
+                    store_mark(func, self.mark)
+                else:
+                    store_legacy_markinfo(func, self.mark)
+                    store_mark(func, self.mark)
+                return func
+        return self.with_args(*args, **kwargs)
+
+
+def get_unpacked_marks(obj):
+    """
+    obtain the unpacked marks that are stored on an object
+    """
+    mark_list = getattr(obj, "pytestmark", [])
+    if not isinstance(mark_list, list):
+        mark_list = [mark_list]
+    return normalize_mark_list(mark_list)
+
+
+def normalize_mark_list(mark_list):
+    """
+    normalizes marker decorating helpers to mark objects
+
+    :type mark_list: List[Union[Mark, Markdecorator]]
+    :rtype: List[Mark]
+    """
+    return [getattr(mark, "mark", mark) for mark in mark_list]  # unpack MarkDecorator
+
+
+def store_mark(obj, mark):
+    """store a Mark on an object
+    this is used to implement the Mark declarations/decorators correctly
+    """
+    assert isinstance(mark, Mark), mark
+    # always reassign name to avoid updating pytestmark
+    # in a reference that was only borrowed
+    obj.pytestmark = get_unpacked_marks(obj) + [mark]
+
+
+def store_legacy_markinfo(func, mark):
+    """create the legacy MarkInfo objects and put them onto the function
+    """
+    if not isinstance(mark, Mark):
+        raise TypeError("got {mark!r} instead of a Mark".format(mark=mark))
+    holder = getattr(func, mark.name, None)
+    if holder is None:
+        holder = MarkInfo.for_mark(mark)
+        setattr(func, mark.name, holder)
+    elif isinstance(holder, MarkInfo):
+        holder.add_mark(mark)
+
+
+def transfer_markers(funcobj, cls, mod):
+    """
+    this function transfers class level markers and module level markers
+    into function level markinfo objects
+
+    this is the main reason why marks are so broken
+    the resolution will involve phasing out function level MarkInfo objects
+
+    """
+    for obj in (cls, mod):
+        for mark in get_unpacked_marks(obj):
+            if not _marked(funcobj, mark):
+                store_legacy_markinfo(funcobj, mark)
+
+
+def _marked(func, mark):
+    """ Returns True if :func: is already marked with :mark:, False otherwise.
+    This can happen if marker is applied to class and the test file is
+    invoked more than once.
+    """
+    try:
+        func_mark = getattr(func, getattr(mark, "combined", mark).name)
+    except AttributeError:
+        return False
+    return any(mark == info.combined for info in func_mark)
+
+
+@attr.s
+class MarkInfo(object):
+    """ Marking object created by :class:`MarkDecorator` instances. """
+
+    _marks = attr.ib(converter=list)
+
+    @_marks.validator
+    def validate_marks(self, attribute, value):
+        for item in value:
+            if not isinstance(item, Mark):
+                raise ValueError(
+                    "MarkInfo expects Mark instances, got {!r} ({!r})".format(
+                        item, type(item)
+                    )
+                )
+
+    combined = attr.ib(
+        repr=False,
+        default=attr.Factory(
+            lambda self: reduce(Mark.combined_with, self._marks), takes_self=True
+        ),
+    )
+
+    name = alias("combined.name", warning=MARK_INFO_ATTRIBUTE)
+    args = alias("combined.args", warning=MARK_INFO_ATTRIBUTE)
+    kwargs = alias("combined.kwargs", warning=MARK_INFO_ATTRIBUTE)
+
+    @classmethod
+    def for_mark(cls, mark):
+        return cls([mark])
+
+    def __repr__(self):
+        return "<MarkInfo {!r}>".format(self.combined)
+
+    def add_mark(self, mark):
+        """ add a MarkInfo with the given args and kwargs. """
+        self._marks.append(mark)
+        self.combined = self.combined.combined_with(mark)
+
+    def __iter__(self):
+        """ yield MarkInfo objects each relating to a marking-call. """
+        return map(MarkInfo.for_mark, self._marks)
+
+
+class MarkGenerator(object):
+    """ Factory for :class:`MarkDecorator` objects - exposed as
+    a ``pytest.mark`` singleton instance.  Example::
+
+         import pytest
+         @pytest.mark.slowtest
+         def test_function():
+            pass
+
+    will set a 'slowtest' :class:`MarkInfo` object
+    on the ``test_function`` object. """
+
+    _config = None
+
+    def __getattr__(self, name):
+        if name[0] == "_":
+            raise AttributeError("Marker name must NOT start with underscore")
+        if self._config is not None:
+            self._check(name)
+        return MarkDecorator(Mark(name, (), {}))
+
+    def _check(self, name):
+        try:
+            if name in self._markers:
+                return
+        except AttributeError:
+            pass
+        self._markers = values = set()
+        for line in self._config.getini("markers"):
+            marker = line.split(":", 1)[0]
+            marker = marker.rstrip()
+            x = marker.split("(", 1)[0]
+            values.add(x)
+        if name not in self._markers:
+            raise AttributeError("%r not a registered marker" % (name,))
+
+
+MARK_GEN = MarkGenerator()
+
+
+class NodeKeywords(MappingMixin):
+    def __init__(self, node):
+        self.node = node
+        self.parent = node.parent
+        self._markers = {node.name: True}
+
+    def __getitem__(self, key):
+        try:
+            return self._markers[key]
+        except KeyError:
+            if self.parent is None:
+                raise
+            return self.parent.keywords[key]
+
+    def __setitem__(self, key, value):
+        self._markers[key] = value
+
+    def __delitem__(self, key):
+        raise ValueError("cannot delete key in keywords dict")
+
+    def __iter__(self):
+        seen = self._seen()
+        return iter(seen)
+
+    def _seen(self):
+        seen = set(self._markers)
+        if self.parent is not None:
+            seen.update(self.parent.keywords)
+        return seen
+
+    def __len__(self):
+        return len(self._seen())
+
+    def __repr__(self):
+        return "<NodeKeywords for node %s>" % (self.node,)
+
+
+@attr.s(cmp=False, hash=False)
+class NodeMarkers(object):
+    """
+    internal strucutre for storing marks belongong to a node
+
+    ..warning::
+
+        unstable api
+
+    """
+
+    own_markers = attr.ib(default=attr.Factory(list))
+
+    def update(self, add_markers):
+        """update the own markers
+        """
+        self.own_markers.extend(add_markers)
+
+    def find(self, name):
+        """
+        find markers in own nodes or parent nodes
+        needs a better place
+        """
+        for mark in self.own_markers:
+            if mark.name == name:
+                yield mark
+
+    def __iter__(self):
+        return iter(self.own_markers)

src/_pytest/monkeypatch.py

@@ -0,0 +1,282 @@
+""" monkeypatching and mocking functionality.  """
+from __future__ import absolute_import, division, print_function
+
+import os
+import sys
+import re
+from contextlib import contextmanager
+
+import six
+from _pytest.fixtures import fixture
+
+RE_IMPORT_ERROR_NAME = re.compile("^No module named (.*)$")
+
+
+@fixture
+def monkeypatch():
+    """The returned ``monkeypatch`` fixture provides these
+    helper methods to modify objects, dictionaries or os.environ::
+
+        monkeypatch.setattr(obj, name, value, raising=True)
+        monkeypatch.delattr(obj, name, raising=True)
+        monkeypatch.setitem(mapping, name, value)
+        monkeypatch.delitem(obj, name, raising=True)
+        monkeypatch.setenv(name, value, prepend=False)
+        monkeypatch.delenv(name, raising=True)
+        monkeypatch.syspath_prepend(path)
+        monkeypatch.chdir(path)
+
+    All modifications will be undone after the requesting
+    test function or fixture has finished. The ``raising``
+    parameter determines if a KeyError or AttributeError
+    will be raised if the set/deletion operation has no target.
+    """
+    mpatch = MonkeyPatch()
+    yield mpatch
+    mpatch.undo()
+
+
+def resolve(name):
+    # simplified from zope.dottedname
+    parts = name.split(".")
+
+    used = parts.pop(0)
+    found = __import__(used)
+    for part in parts:
+        used += "." + part
+        try:
+            found = getattr(found, part)
+        except AttributeError:
+            pass
+        else:
+            continue
+        # we use explicit un-nesting of the handling block in order
+        # to avoid nested exceptions on python 3
+        try:
+            __import__(used)
+        except ImportError as ex:
+            # str is used for py2 vs py3
+            expected = str(ex).split()[-1]
+            if expected == used:
+                raise
+            else:
+                raise ImportError("import error in %s: %s" % (used, ex))
+        found = annotated_getattr(found, part, used)
+    return found
+
+
+def annotated_getattr(obj, name, ann):
+    try:
+        obj = getattr(obj, name)
+    except AttributeError:
+        raise AttributeError(
+            "%r object at %s has no attribute %r" % (type(obj).__name__, ann, name)
+        )
+    return obj
+
+
+def derive_importpath(import_path, raising):
+    if not isinstance(import_path, six.string_types) or "." not in import_path:
+        raise TypeError("must be absolute import path string, not %r" % (import_path,))
+    module, attr = import_path.rsplit(".", 1)
+    target = resolve(module)
+    if raising:
+        annotated_getattr(target, attr, ann=module)
+    return attr, target
+
+
+class Notset(object):
+    def __repr__(self):
+        return "<notset>"
+
+
+notset = Notset()
+
+
+class MonkeyPatch(object):
+    """ Object returned by the ``monkeypatch`` fixture keeping a record of setattr/item/env/syspath changes.
+    """
+
+    def __init__(self):
+        self._setattr = []
+        self._setitem = []
+        self._cwd = None
+        self._savesyspath = None
+
+    @contextmanager
+    def context(self):
+        """
+        Context manager that returns a new :class:`MonkeyPatch` object which
+        undoes any patching done inside the ``with`` block upon exit:
+
+        .. code-block:: python
+
+            import functools
+            def test_partial(monkeypatch):
+                with monkeypatch.context() as m:
+                    m.setattr(functools, "partial", 3)
+
+        Useful in situations where it is desired to undo some patches before the test ends,
+        such as mocking ``stdlib`` functions that might break pytest itself if mocked (for examples
+        of this see `#3290 <https://github.com/pytest-dev/pytest/issues/3290>`_.
+        """
+        m = MonkeyPatch()
+        try:
+            yield m
+        finally:
+            m.undo()
+
+    def setattr(self, target, name, value=notset, raising=True):
+        """ Set attribute value on target, memorizing the old value.
+        By default raise AttributeError if the attribute did not exist.
+
+        For convenience you can specify a string as ``target`` which
+        will be interpreted as a dotted import path, with the last part
+        being the attribute name.  Example:
+        ``monkeypatch.setattr("os.getcwd", lambda: "/")``
+        would set the ``getcwd`` function of the ``os`` module.
+
+        The ``raising`` value determines if the setattr should fail
+        if the attribute is not already present (defaults to True
+        which means it will raise).
+        """
+        __tracebackhide__ = True
+        import inspect
+
+        if value is notset:
+            if not isinstance(target, six.string_types):
+                raise TypeError(
+                    "use setattr(target, name, value) or "
+                    "setattr(target, value) with target being a dotted "
+                    "import string"
+                )
+            value = name
+            name, target = derive_importpath(target, raising)
+
+        oldval = getattr(target, name, notset)
+        if raising and oldval is notset:
+            raise AttributeError("%r has no attribute %r" % (target, name))
+
+        # avoid class descriptors like staticmethod/classmethod
+        if inspect.isclass(target):
+            oldval = target.__dict__.get(name, notset)
+        self._setattr.append((target, name, oldval))
+        setattr(target, name, value)
+
+    def delattr(self, target, name=notset, raising=True):
+        """ Delete attribute ``name`` from ``target``, by default raise
+        AttributeError it the attribute did not previously exist.
+
+        If no ``name`` is specified and ``target`` is a string
+        it will be interpreted as a dotted import path with the
+        last part being the attribute name.
+
+        If ``raising`` is set to False, no exception will be raised if the
+        attribute is missing.
+        """
+        __tracebackhide__ = True
+        if name is notset:
+            if not isinstance(target, six.string_types):
+                raise TypeError(
+                    "use delattr(target, name) or "
+                    "delattr(target) with target being a dotted "
+                    "import string"
+                )
+            name, target = derive_importpath(target, raising)
+
+        if not hasattr(target, name):
+            if raising:
+                raise AttributeError(name)
+        else:
+            self._setattr.append((target, name, getattr(target, name, notset)))
+            delattr(target, name)
+
+    def setitem(self, dic, name, value):
+        """ Set dictionary entry ``name`` to value. """
+        self._setitem.append((dic, name, dic.get(name, notset)))
+        dic[name] = value
+
+    def delitem(self, dic, name, raising=True):
+        """ Delete ``name`` from dict. Raise KeyError if it doesn't exist.
+
+        If ``raising`` is set to False, no exception will be raised if the
+        key is missing.
+        """
+        if name not in dic:
+            if raising:
+                raise KeyError(name)
+        else:
+            self._setitem.append((dic, name, dic.get(name, notset)))
+            del dic[name]
+
+    def setenv(self, name, value, prepend=None):
+        """ Set environment variable ``name`` to ``value``.  If ``prepend``
+        is a character, read the current environment variable value
+        and prepend the ``value`` adjoined with the ``prepend`` character."""
+        value = str(value)
+        if prepend and name in os.environ:
+            value = value + prepend + os.environ[name]
+        self.setitem(os.environ, name, value)
+
+    def delenv(self, name, raising=True):
+        """ Delete ``name`` from the environment. Raise KeyError it does not
+        exist.
+
+        If ``raising`` is set to False, no exception will be raised if the
+        environment variable is missing.
+        """
+        self.delitem(os.environ, name, raising=raising)
+
+    def syspath_prepend(self, path):
+        """ Prepend ``path`` to ``sys.path`` list of import locations. """
+        if self._savesyspath is None:
+            self._savesyspath = sys.path[:]
+        sys.path.insert(0, str(path))
+
+    def chdir(self, path):
+        """ Change the current working directory to the specified path.
+        Path can be a string or a py.path.local object.
+        """
+        if self._cwd is None:
+            self._cwd = os.getcwd()
+        if hasattr(path, "chdir"):
+            path.chdir()
+        else:
+            os.chdir(path)
+
+    def undo(self):
+        """ Undo previous changes.  This call consumes the
+        undo stack. Calling it a second time has no effect unless
+        you do more monkeypatching after the undo call.
+
+        There is generally no need to call `undo()`, since it is
+        called automatically during tear-down.
+
+        Note that the same `monkeypatch` fixture is used across a
+        single test function invocation. If `monkeypatch` is used both by
+        the test function itself and one of the test fixtures,
+        calling `undo()` will undo all of the changes made in
+        both functions.
+        """
+        for obj, name, value in reversed(self._setattr):
+            if value is not notset:
+                setattr(obj, name, value)
+            else:
+                delattr(obj, name)
+        self._setattr[:] = []
+        for dictionary, name, value in reversed(self._setitem):
+            if value is notset:
+                try:
+                    del dictionary[name]
+                except KeyError:
+                    pass  # was already deleted, so we have the desired state
+            else:
+                dictionary[name] = value
+        self._setitem[:] = []
+        if self._savesyspath is not None:
+            sys.path[:] = self._savesyspath
+            self._savesyspath = None
+
+        if self._cwd is not None:
+            os.chdir(self._cwd)
+            self._cwd = None

src/_pytest/nodes.py

@@ -0,0 +1,425 @@
+from __future__ import absolute_import, division, print_function
+import os
+
+import six
+import py
+import attr
+
+import _pytest
+import _pytest._code
+
+from _pytest.mark.structures import NodeKeywords, MarkInfo
+
+SEP = "/"
+
+tracebackcutdir = py.path.local(_pytest.__file__).dirpath()
+
+
+def _splitnode(nodeid):
+    """Split a nodeid into constituent 'parts'.
+
+    Node IDs are strings, and can be things like:
+        ''
+        'testing/code'
+        'testing/code/test_excinfo.py'
+        'testing/code/test_excinfo.py::TestFormattedExcinfo::()'
+
+    Return values are lists e.g.
+        []
+        ['testing', 'code']
+        ['testing', 'code', 'test_excinfo.py']
+        ['testing', 'code', 'test_excinfo.py', 'TestFormattedExcinfo', '()']
+    """
+    if nodeid == "":
+        # If there is no root node at all, return an empty list so the caller's logic can remain sane
+        return []
+    parts = nodeid.split(SEP)
+    # Replace single last element 'test_foo.py::Bar::()' with multiple elements 'test_foo.py', 'Bar', '()'
+    parts[-1:] = parts[-1].split("::")
+    return parts
+
+
+def ischildnode(baseid, nodeid):
+    """Return True if the nodeid is a child node of the baseid.
+
+    E.g. 'foo/bar::Baz::()' is a child of 'foo', 'foo/bar' and 'foo/bar::Baz', but not of 'foo/blorp'
+    """
+    base_parts = _splitnode(baseid)
+    node_parts = _splitnode(nodeid)
+    if len(node_parts) < len(base_parts):
+        return False
+    return node_parts[: len(base_parts)] == base_parts
+
+
+@attr.s
+class _CompatProperty(object):
+    name = attr.ib()
+
+    def __get__(self, obj, owner):
+        if obj is None:
+            return self
+
+        # TODO: reenable in the features branch
+        # warnings.warn(
+        #     "usage of {owner!r}.{name} is deprecated, please use pytest.{name} instead".format(
+        #         name=self.name, owner=type(owner).__name__),
+        #     PendingDeprecationWarning, stacklevel=2)
+        return getattr(__import__("pytest"), self.name)
+
+
+class Node(object):
+    """ base class for Collector and Item the test collection tree.
+    Collector subclasses have children, Items are terminal nodes."""
+
+    def __init__(
+        self, name, parent=None, config=None, session=None, fspath=None, nodeid=None
+    ):
+        #: a unique name within the scope of the parent node
+        self.name = name
+
+        #: the parent collector node.
+        self.parent = parent
+
+        #: the pytest config object
+        self.config = config or parent.config
+
+        #: the session this node is part of
+        self.session = session or parent.session
+
+        #: filesystem path where this node was collected from (can be None)
+        self.fspath = fspath or getattr(parent, "fspath", None)
+
+        #: keywords/markers collected from all scopes
+        self.keywords = NodeKeywords(self)
+
+        #: the marker objects belonging to this node
+        self.own_markers = []
+
+        #: allow adding of extra keywords to use for matching
+        self.extra_keyword_matches = set()
+
+        # used for storing artificial fixturedefs for direct parametrization
+        self._name2pseudofixturedef = {}
+
+        if nodeid is not None:
+            self._nodeid = nodeid
+        else:
+            assert parent is not None
+            self._nodeid = self.parent.nodeid + "::" + self.name
+
+    @property
+    def ihook(self):
+        """ fspath sensitive hook proxy used to call pytest hooks"""
+        return self.session.gethookproxy(self.fspath)
+
+    Module = _CompatProperty("Module")
+    Class = _CompatProperty("Class")
+    Instance = _CompatProperty("Instance")
+    Function = _CompatProperty("Function")
+    File = _CompatProperty("File")
+    Item = _CompatProperty("Item")
+
+    def _getcustomclass(self, name):
+        maybe_compatprop = getattr(type(self), name)
+        if isinstance(maybe_compatprop, _CompatProperty):
+            return getattr(__import__("pytest"), name)
+        else:
+            cls = getattr(self, name)
+            # TODO: reenable in the features branch
+            # warnings.warn("use of node.%s is deprecated, "
+            #    "use pytest_pycollect_makeitem(...) to create custom "
+            #    "collection nodes" % name, category=DeprecationWarning)
+        return cls
+
+    def __repr__(self):
+        return "<%s %r>" % (self.__class__.__name__, getattr(self, "name", None))
+
+    def warn(self, code, message):
+        """ generate a warning with the given code and message for this
+        item. """
+        assert isinstance(code, str)
+        fslocation = getattr(self, "location", None)
+        if fslocation is None:
+            fslocation = getattr(self, "fspath", None)
+        self.ihook.pytest_logwarning.call_historic(
+            kwargs=dict(
+                code=code, message=message, nodeid=self.nodeid, fslocation=fslocation
+            )
+        )
+
+    # methods for ordering nodes
+    @property
+    def nodeid(self):
+        """ a ::-separated string denoting its collection tree address. """
+        return self._nodeid
+
+    def __hash__(self):
+        return hash(self.nodeid)
+
+    def setup(self):
+        pass
+
+    def teardown(self):
+        pass
+
+    def listchain(self):
+        """ return list of all parent collectors up to self,
+            starting from root of collection tree. """
+        chain = []
+        item = self
+        while item is not None:
+            chain.append(item)
+            item = item.parent
+        chain.reverse()
+        return chain
+
+    def add_marker(self, marker, append=True):
+        """dynamically add a marker object to the node.
+
+        :type marker: ``str`` or ``pytest.mark.*``  object
+        :param marker:
+            ``append=True`` whether to append the marker,
+            if ``False`` insert at position ``0``.
+        """
+        from _pytest.mark import MarkDecorator, MARK_GEN
+
+        if isinstance(marker, six.string_types):
+            marker = getattr(MARK_GEN, marker)
+        elif not isinstance(marker, MarkDecorator):
+            raise ValueError("is not a string or pytest.mark.* Marker")
+        self.keywords[marker.name] = marker
+        if append:
+            self.own_markers.append(marker.mark)
+        else:
+            self.own_markers.insert(0, marker.mark)
+
+    def iter_markers(self, name=None):
+        """
+        :param name: if given, filter the results by the name attribute
+
+        iterate over all markers of the node
+        """
+        return (x[1] for x in self.iter_markers_with_node(name=name))
+
+    def iter_markers_with_node(self, name=None):
+        """
+        :param name: if given, filter the results by the name attribute
+
+        iterate over all markers of the node
+        returns sequence of tuples (node, mark)
+        """
+        for node in reversed(self.listchain()):
+            for mark in node.own_markers:
+                if name is None or getattr(mark, "name", None) == name:
+                    yield node, mark
+
+    def get_closest_marker(self, name, default=None):
+        """return the first marker matching the name, from closest (for example function) to farther level (for example
+        module level).
+
+        :param default: fallback return value of no marker was found
+        :param name: name to filter by
+        """
+        return next(self.iter_markers(name=name), default)
+
+    def get_marker(self, name):
+        """ get a marker object from this node or None if
+        the node doesn't have a marker with that name.
+
+        .. deprecated:: 3.6
+            This function has been deprecated in favor of
+            :meth:`Node.get_closest_marker <_pytest.nodes.Node.get_closest_marker>` and
+            :meth:`Node.iter_markers <_pytest.nodes.Node.iter_markers>`, see :ref:`update marker code`
+            for more details.
+        """
+        markers = list(self.iter_markers(name=name))
+        if markers:
+            return MarkInfo(markers)
+
+    def listextrakeywords(self):
+        """ Return a set of all extra keywords in self and any parents."""
+        extra_keywords = set()
+        for item in self.listchain():
+            extra_keywords.update(item.extra_keyword_matches)
+        return extra_keywords
+
+    def listnames(self):
+        return [x.name for x in self.listchain()]
+
+    def addfinalizer(self, fin):
+        """ register a function to be called when this node is finalized.
+
+        This method can only be called when this node is active
+        in a setup chain, for example during self.setup().
+        """
+        self.session._setupstate.addfinalizer(fin, self)
+
+    def getparent(self, cls):
+        """ get the next parent node (including ourself)
+        which is an instance of the given class"""
+        current = self
+        while current and not isinstance(current, cls):
+            current = current.parent
+        return current
+
+    def _prunetraceback(self, excinfo):
+        pass
+
+    def _repr_failure_py(self, excinfo, style=None):
+        fm = self.session._fixturemanager
+        if excinfo.errisinstance(fm.FixtureLookupError):
+            return excinfo.value.formatrepr()
+        tbfilter = True
+        if self.config.option.fulltrace:
+            style = "long"
+        else:
+            tb = _pytest._code.Traceback([excinfo.traceback[-1]])
+            self._prunetraceback(excinfo)
+            if len(excinfo.traceback) == 0:
+                excinfo.traceback = tb
+            tbfilter = False  # prunetraceback already does it
+            if style == "auto":
+                style = "long"
+        # XXX should excinfo.getrepr record all data and toterminal() process it?
+        if style is None:
+            if self.config.option.tbstyle == "short":
+                style = "short"
+            else:
+                style = "long"
+
+        try:
+            os.getcwd()
+            abspath = False
+        except OSError:
+            abspath = True
+
+        return excinfo.getrepr(
+            funcargs=True,
+            abspath=abspath,
+            showlocals=self.config.option.showlocals,
+            style=style,
+            tbfilter=tbfilter,
+        )
+
+    repr_failure = _repr_failure_py
+
+
+class Collector(Node):
+    """ Collector instances create children through collect()
+        and thus iteratively build a tree.
+    """
+
+    class CollectError(Exception):
+        """ an error during collection, contains a custom message. """
+
+    def collect(self):
+        """ returns a list of children (items and collectors)
+            for this collection node.
+        """
+        raise NotImplementedError("abstract")
+
+    def repr_failure(self, excinfo):
+        """ represent a collection failure. """
+        if excinfo.errisinstance(self.CollectError):
+            exc = excinfo.value
+            return str(exc.args[0])
+        return self._repr_failure_py(excinfo, style="short")
+
+    def _prunetraceback(self, excinfo):
+        if hasattr(self, "fspath"):
+            traceback = excinfo.traceback
+            ntraceback = traceback.cut(path=self.fspath)
+            if ntraceback == traceback:
+                ntraceback = ntraceback.cut(excludepath=tracebackcutdir)
+            excinfo.traceback = ntraceback.filter()
+
+
+def _check_initialpaths_for_relpath(session, fspath):
+    for initial_path in session._initialpaths:
+        if fspath.common(initial_path) == initial_path:
+            return fspath.relto(initial_path.dirname)
+
+
+class FSCollector(Collector):
+    def __init__(self, fspath, parent=None, config=None, session=None, nodeid=None):
+        fspath = py.path.local(fspath)  # xxx only for test_resultlog.py?
+        name = fspath.basename
+        if parent is not None:
+            rel = fspath.relto(parent.fspath)
+            if rel:
+                name = rel
+            name = name.replace(os.sep, SEP)
+        self.fspath = fspath
+
+        session = session or parent.session
+
+        if nodeid is None:
+            nodeid = self.fspath.relto(session.config.rootdir)
+
+            if not nodeid:
+                nodeid = _check_initialpaths_for_relpath(session, fspath)
+            if nodeid and os.sep != SEP:
+                nodeid = nodeid.replace(os.sep, SEP)
+
+        super(FSCollector, self).__init__(
+            name, parent, config, session, nodeid=nodeid, fspath=fspath
+        )
+
+
+class File(FSCollector):
+    """ base class for collecting tests from a file. """
+
+
+class Item(Node):
+    """ a basic test invocation item. Note that for a single function
+    there might be multiple test invocation items.
+    """
+
+    nextitem = None
+
+    def __init__(self, name, parent=None, config=None, session=None, nodeid=None):
+        super(Item, self).__init__(name, parent, config, session, nodeid=nodeid)
+        self._report_sections = []
+
+        #: user properties is a list of tuples (name, value) that holds user
+        #: defined properties for this test.
+        self.user_properties = []
+
+    def add_report_section(self, when, key, content):
+        """
+        Adds a new report section, similar to what's done internally to add stdout and
+        stderr captured output::
+
+            item.add_report_section("call", "stdout", "report section contents")
+
+        :param str when:
+            One of the possible capture states, ``"setup"``, ``"call"``, ``"teardown"``.
+        :param str key:
+            Name of the section, can be customized at will. Pytest uses ``"stdout"`` and
+            ``"stderr"`` internally.
+
+        :param str content:
+            The full contents as a string.
+        """
+        if content:
+            self._report_sections.append((when, key, content))
+
+    def reportinfo(self):
+        return self.fspath, None, ""
+
+    @property
+    def location(self):
+        try:
+            return self._location
+        except AttributeError:
+            location = self.reportinfo()
+            # bestrelpath is a quite slow function
+            cache = self.config.__dict__.setdefault("_bestrelpathcache", {})
+            try:
+                fspath = cache[location[0]]
+            except KeyError:
+                fspath = self.session.fspath.bestrelpath(location[0])
+                cache[location[0]] = fspath
+            location = (fspath, location[1], str(location[2]))
+            self._location = location
+            return location

src/_pytest/nose.py

@@ -0,0 +1,72 @@
+""" run test suites written for nose. """
+from __future__ import absolute_import, division, print_function
+
+import sys
+
+from _pytest import unittest, runner, python
+from _pytest.config import hookimpl
+
+
+def get_skip_exceptions():
+    skip_classes = set()
+    for module_name in ("unittest", "unittest2", "nose"):
+        mod = sys.modules.get(module_name)
+        if hasattr(mod, "SkipTest"):
+            skip_classes.add(mod.SkipTest)
+    return tuple(skip_classes)
+
+
+def pytest_runtest_makereport(item, call):
+    if call.excinfo and call.excinfo.errisinstance(get_skip_exceptions()):
+        # let's substitute the excinfo with a pytest.skip one
+        call2 = call.__class__(lambda: runner.skip(str(call.excinfo.value)), call.when)
+        call.excinfo = call2.excinfo
+
+
+@hookimpl(trylast=True)
+def pytest_runtest_setup(item):
+    if is_potential_nosetest(item):
+        if isinstance(item.parent, python.Generator):
+            gen = item.parent
+            if not hasattr(gen, "_nosegensetup"):
+                call_optional(gen.obj, "setup")
+                if isinstance(gen.parent, python.Instance):
+                    call_optional(gen.parent.obj, "setup")
+                gen._nosegensetup = True
+        if not call_optional(item.obj, "setup"):
+            # call module level setup if there is no object level one
+            call_optional(item.parent.obj, "setup")
+        # XXX this implies we only call teardown when setup worked
+        item.session._setupstate.addfinalizer((lambda: teardown_nose(item)), item)
+
+
+def teardown_nose(item):
+    if is_potential_nosetest(item):
+        if not call_optional(item.obj, "teardown"):
+            call_optional(item.parent.obj, "teardown")
+        # if hasattr(item.parent, '_nosegensetup'):
+        #    #call_optional(item._nosegensetup, 'teardown')
+        #    del item.parent._nosegensetup
+
+
+def pytest_make_collect_report(collector):
+    if isinstance(collector, python.Generator):
+        call_optional(collector.obj, "setup")
+
+
+def is_potential_nosetest(item):
+    # extra check needed since we do not do nose style setup/teardown
+    # on direct unittest style classes
+    return isinstance(item, python.Function) and not isinstance(
+        item, unittest.TestCaseFunction
+    )
+
+
+def call_optional(obj, name):
+    method = getattr(obj, name, None)
+    isfixture = hasattr(method, "_pytestfixturefunction")
+    if method is not None and not isfixture and callable(method):
+        # If there's any problems allow the exception to raise rather than
+        # silently ignoring them
+        method()
+        return True

src/_pytest/outcomes.py

@@ -0,0 +1,158 @@
+"""
+exception classes and constants handling test outcomes
+as well as functions creating them
+"""
+from __future__ import absolute_import, division, print_function
+import py
+import sys
+
+
+class OutcomeException(BaseException):
+    """ OutcomeException and its subclass instances indicate and
+        contain info about test and collection outcomes.
+    """
+
+    def __init__(self, msg=None, pytrace=True):
+        BaseException.__init__(self, msg)
+        self.msg = msg
+        self.pytrace = pytrace
+
+    def __repr__(self):
+        if self.msg:
+            val = self.msg
+            if isinstance(val, bytes):
+                val = py._builtin._totext(val, errors="replace")
+            return val
+        return "<%s instance>" % (self.__class__.__name__,)
+
+    __str__ = __repr__
+
+
+TEST_OUTCOME = (OutcomeException, Exception)
+
+
+class Skipped(OutcomeException):
+    # XXX hackish: on 3k we fake to live in the builtins
+    # in order to have Skipped exception printing shorter/nicer
+    __module__ = "builtins"
+
+    def __init__(self, msg=None, pytrace=True, allow_module_level=False):
+        OutcomeException.__init__(self, msg=msg, pytrace=pytrace)
+        self.allow_module_level = allow_module_level
+
+
+class Failed(OutcomeException):
+    """ raised from an explicit call to pytest.fail() """
+
+    __module__ = "builtins"
+
+
+class Exit(KeyboardInterrupt):
+    """ raised for immediate program exits (no tracebacks/summaries)"""
+
+    def __init__(self, msg="unknown reason"):
+        self.msg = msg
+        KeyboardInterrupt.__init__(self, msg)
+
+
+# exposed helper methods
+
+
+def exit(msg):
+    """ exit testing process as if KeyboardInterrupt was triggered. """
+    __tracebackhide__ = True
+    raise Exit(msg)
+
+
+exit.Exception = Exit
+
+
+def skip(msg="", **kwargs):
+    """ skip an executing test with the given message.  Note: it's usually
+    better to use the pytest.mark.skipif marker to declare a test to be
+    skipped under certain conditions like mismatching platforms or
+    dependencies.  See the pytest_skipping plugin for details.
+
+    :kwarg bool allow_module_level: allows this function to be called at
+        module level, skipping the rest of the module. Default to False.
+    """
+    __tracebackhide__ = True
+    allow_module_level = kwargs.pop("allow_module_level", False)
+    if kwargs:
+        keys = [k for k in kwargs.keys()]
+        raise TypeError("unexpected keyword arguments: {}".format(keys))
+    raise Skipped(msg=msg, allow_module_level=allow_module_level)
+
+
+skip.Exception = Skipped
+
+
+def fail(msg="", pytrace=True):
+    """ explicitly fail a currently-executing test with the given Message.
+
+    :arg pytrace: if false the msg represents the full failure information
+                  and no python traceback will be reported.
+    """
+    __tracebackhide__ = True
+    raise Failed(msg=msg, pytrace=pytrace)
+
+
+fail.Exception = Failed
+
+
+class XFailed(fail.Exception):
+    """ raised from an explicit call to pytest.xfail() """
+
+
+def xfail(reason=""):
+    """ xfail an executing test or setup functions with the given reason."""
+    __tracebackhide__ = True
+    raise XFailed(reason)
+
+
+xfail.Exception = XFailed
+
+
+def importorskip(modname, minversion=None):
+    """ return imported module if it has at least "minversion" as its
+    __version__ attribute.  If no minversion is specified the a skip
+    is only triggered if the module can not be imported.
+    """
+    import warnings
+
+    __tracebackhide__ = True
+    compile(modname, "", "eval")  # to catch syntaxerrors
+    should_skip = False
+
+    with warnings.catch_warnings():
+        # make sure to ignore ImportWarnings that might happen because
+        # of existing directories with the same name we're trying to
+        # import but without a __init__.py file
+        warnings.simplefilter("ignore")
+        try:
+            __import__(modname)
+        except ImportError:
+            # Do not raise chained exception here(#1485)
+            should_skip = True
+    if should_skip:
+        raise Skipped("could not import %r" % (modname,), allow_module_level=True)
+    mod = sys.modules[modname]
+    if minversion is None:
+        return mod
+    verattr = getattr(mod, "__version__", None)
+    if minversion is not None:
+        try:
+            from pkg_resources import parse_version as pv
+        except ImportError:
+            raise Skipped(
+                "we have a required version for %r but can not import "
+                "pkg_resources to parse version strings." % (modname,),
+                allow_module_level=True,
+            )
+        if verattr is None or pv(verattr) < pv(minversion):
+            raise Skipped(
+                "module %r has __version__ %r, required is: %r"
+                % (modname, verattr, minversion),
+                allow_module_level=True,
+            )
+    return mod

src/_pytest/pastebin.py

@@ -0,0 +1,109 @@
+""" submit failure or test session information to a pastebin service. """
+from __future__ import absolute_import, division, print_function
+
+import pytest
+import six
+import sys
+import tempfile
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("terminal reporting")
+    group._addoption(
+        "--pastebin",
+        metavar="mode",
+        action="store",
+        dest="pastebin",
+        default=None,
+        choices=["failed", "all"],
+        help="send failed|all info to bpaste.net pastebin service.",
+    )
+
+
+@pytest.hookimpl(trylast=True)
+def pytest_configure(config):
+    if config.option.pastebin == "all":
+        tr = config.pluginmanager.getplugin("terminalreporter")
+        # if no terminal reporter plugin is present, nothing we can do here;
+        # this can happen when this function executes in a slave node
+        # when using pytest-xdist, for example
+        if tr is not None:
+            # pastebin file will be utf-8 encoded binary file
+            config._pastebinfile = tempfile.TemporaryFile("w+b")
+            oldwrite = tr._tw.write
+
+            def tee_write(s, **kwargs):
+                oldwrite(s, **kwargs)
+                if isinstance(s, six.text_type):
+                    s = s.encode("utf-8")
+                config._pastebinfile.write(s)
+
+            tr._tw.write = tee_write
+
+
+def pytest_unconfigure(config):
+    if hasattr(config, "_pastebinfile"):
+        # get terminal contents and delete file
+        config._pastebinfile.seek(0)
+        sessionlog = config._pastebinfile.read()
+        config._pastebinfile.close()
+        del config._pastebinfile
+        # undo our patching in the terminal reporter
+        tr = config.pluginmanager.getplugin("terminalreporter")
+        del tr._tw.__dict__["write"]
+        # write summary
+        tr.write_sep("=", "Sending information to Paste Service")
+        pastebinurl = create_new_paste(sessionlog)
+        tr.write_line("pastebin session-log: %s\n" % pastebinurl)
+
+
+def create_new_paste(contents):
+    """
+    Creates a new paste using bpaste.net service.
+
+    :contents: paste contents as utf-8 encoded bytes
+    :returns: url to the pasted contents
+    """
+    import re
+
+    if sys.version_info < (3, 0):
+        from urllib import urlopen, urlencode
+    else:
+        from urllib.request import urlopen
+        from urllib.parse import urlencode
+
+    params = {
+        "code": contents,
+        "lexer": "python3" if sys.version_info[0] == 3 else "python",
+        "expiry": "1week",
+    }
+    url = "https://bpaste.net"
+    response = urlopen(url, data=urlencode(params).encode("ascii")).read()
+    m = re.search(r'href="/raw/(\w+)"', response.decode("utf-8"))
+    if m:
+        return "%s/show/%s" % (url, m.group(1))
+    else:
+        return "bad response: " + response
+
+
+def pytest_terminal_summary(terminalreporter):
+    import _pytest.config
+
+    if terminalreporter.config.option.pastebin != "failed":
+        return
+    tr = terminalreporter
+    if "failed" in tr.stats:
+        terminalreporter.write_sep("=", "Sending information to Paste Service")
+        for rep in terminalreporter.stats.get("failed"):
+            try:
+                msg = rep.longrepr.reprtraceback.reprentries[-1].reprfileloc
+            except AttributeError:
+                msg = tr._getfailureheadline(rep)
+            tw = _pytest.config.create_terminal_writer(
+                terminalreporter.config, stringio=True
+            )
+            rep.toterminal(tw)
+            s = tw.stringio.getvalue()
+            assert len(s)
+            pastebinurl = create_new_paste(s)
+            tr.write_line("%s --> %s" % (msg, pastebinurl))

src/_pytest/paths.py

@@ -0,0 +1,13 @@
+from .compat import Path
+from os.path import expanduser, expandvars, isabs
+
+
+def resolve_from_str(input, root):
+    assert not isinstance(input, Path), "would break on py2"
+    root = Path(root)
+    input = expanduser(input)
+    input = expandvars(input)
+    if isabs(input):
+        return Path(input)
+    else:
+        return root.joinpath(input)

src/_pytest/python_api.py

@@ -0,0 +1,674 @@
+import math
+import sys
+
+import py
+from six.moves import zip, filterfalse
+from more_itertools.more import always_iterable
+
+from _pytest.compat import isclass
+
+from _pytest.compat import Mapping, Sequence
+from _pytest.compat import STRING_TYPES
+
+from _pytest.outcomes import fail
+import _pytest._code
+
+BASE_TYPE = (type, STRING_TYPES)
+
+
+def _cmp_raises_type_error(self, other):
+    """__cmp__ implementation which raises TypeError. Used
+    by Approx base classes to implement only == and != and raise a
+    TypeError for other comparisons.
+
+    Needed in Python 2 only, Python 3 all it takes is not implementing the
+    other operators at all.
+    """
+    __tracebackhide__ = True
+    raise TypeError(
+        "Comparison operators other than == and != not supported by approx objects"
+    )
+
+
+# builtin pytest.approx helper
+
+
+class ApproxBase(object):
+    """
+    Provide shared utilities for making approximate comparisons between numbers
+    or sequences of numbers.
+    """
+
+    # Tell numpy to use our `__eq__` operator instead of its
+    __array_ufunc__ = None
+    __array_priority__ = 100
+
+    def __init__(self, expected, rel=None, abs=None, nan_ok=False):
+        self.expected = expected
+        self.abs = abs
+        self.rel = rel
+        self.nan_ok = nan_ok
+
+    def __repr__(self):
+        raise NotImplementedError
+
+    def __eq__(self, actual):
+        return all(
+            a == self._approx_scalar(x) for a, x in self._yield_comparisons(actual)
+        )
+
+    __hash__ = None
+
+    def __ne__(self, actual):
+        return not (actual == self)
+
+    if sys.version_info[0] == 2:
+        __cmp__ = _cmp_raises_type_error
+
+    def _approx_scalar(self, x):
+        return ApproxScalar(x, rel=self.rel, abs=self.abs, nan_ok=self.nan_ok)
+
+    def _yield_comparisons(self, actual):
+        """
+        Yield all the pairs of numbers to be compared.  This is used to
+        implement the `__eq__` method.
+        """
+        raise NotImplementedError
+
+
+class ApproxNumpy(ApproxBase):
+    """
+    Perform approximate comparisons for numpy arrays.
+    """
+
+    def __repr__(self):
+        # It might be nice to rewrite this function to account for the
+        # shape of the array...
+        import numpy as np
+
+        list_scalars = []
+        for x in np.ndindex(self.expected.shape):
+            list_scalars.append(self._approx_scalar(np.asscalar(self.expected[x])))
+
+        return "approx({!r})".format(list_scalars)
+
+    if sys.version_info[0] == 2:
+        __cmp__ = _cmp_raises_type_error
+
+    def __eq__(self, actual):
+        import numpy as np
+
+        # self.expected is supposed to always be an array here
+
+        if not np.isscalar(actual):
+            try:
+                actual = np.asarray(actual)
+            except:  # noqa
+                raise TypeError("cannot compare '{}' to numpy.ndarray".format(actual))
+
+        if not np.isscalar(actual) and actual.shape != self.expected.shape:
+            return False
+
+        return ApproxBase.__eq__(self, actual)
+
+    def _yield_comparisons(self, actual):
+        import numpy as np
+
+        # `actual` can either be a numpy array or a scalar, it is treated in
+        # `__eq__` before being passed to `ApproxBase.__eq__`, which is the
+        # only method that calls this one.
+
+        if np.isscalar(actual):
+            for i in np.ndindex(self.expected.shape):
+                yield actual, np.asscalar(self.expected[i])
+        else:
+            for i in np.ndindex(self.expected.shape):
+                yield np.asscalar(actual[i]), np.asscalar(self.expected[i])
+
+
+class ApproxMapping(ApproxBase):
+    """
+    Perform approximate comparisons for mappings where the values are numbers
+    (the keys can be anything).
+    """
+
+    def __repr__(self):
+        return "approx({!r})".format(
+            {k: self._approx_scalar(v) for k, v in self.expected.items()}
+        )
+
+    def __eq__(self, actual):
+        if set(actual.keys()) != set(self.expected.keys()):
+            return False
+
+        return ApproxBase.__eq__(self, actual)
+
+    def _yield_comparisons(self, actual):
+        for k in self.expected.keys():
+            yield actual[k], self.expected[k]
+
+
+class ApproxSequence(ApproxBase):
+    """
+    Perform approximate comparisons for sequences of numbers.
+    """
+
+    def __repr__(self):
+        seq_type = type(self.expected)
+        if seq_type not in (tuple, list, set):
+            seq_type = list
+        return "approx({!r})".format(
+            seq_type(self._approx_scalar(x) for x in self.expected)
+        )
+
+    def __eq__(self, actual):
+        if len(actual) != len(self.expected):
+            return False
+        return ApproxBase.__eq__(self, actual)
+
+    def _yield_comparisons(self, actual):
+        return zip(actual, self.expected)
+
+
+class ApproxScalar(ApproxBase):
+    """
+    Perform approximate comparisons for single numbers only.
+    """
+
+    DEFAULT_ABSOLUTE_TOLERANCE = 1e-12
+    DEFAULT_RELATIVE_TOLERANCE = 1e-6
+
+    def __repr__(self):
+        """
+        Return a string communicating both the expected value and the tolerance
+        for the comparison being made, e.g. '1.0 +- 1e-6'.  Use the unicode
+        plus/minus symbol if this is python3 (it's too hard to get right for
+        python2).
+        """
+        if isinstance(self.expected, complex):
+            return str(self.expected)
+
+        # Infinities aren't compared using tolerances, so don't show a
+        # tolerance.
+        if math.isinf(self.expected):
+            return str(self.expected)
+
+        # If a sensible tolerance can't be calculated, self.tolerance will
+        # raise a ValueError.  In this case, display '???'.
+        try:
+            vetted_tolerance = "{:.1e}".format(self.tolerance)
+        except ValueError:
+            vetted_tolerance = "???"
+
+        if sys.version_info[0] == 2:
+            return "{} +- {}".format(self.expected, vetted_tolerance)
+        else:
+            return u"{} \u00b1 {}".format(self.expected, vetted_tolerance)
+
+    def __eq__(self, actual):
+        """
+        Return true if the given value is equal to the expected value within
+        the pre-specified tolerance.
+        """
+        if _is_numpy_array(actual):
+            return ApproxNumpy(actual, self.abs, self.rel, self.nan_ok) == self.expected
+
+        # Short-circuit exact equality.
+        if actual == self.expected:
+            return True
+
+        # Allow the user to control whether NaNs are considered equal to each
+        # other or not.  The abs() calls are for compatibility with complex
+        # numbers.
+        if math.isnan(abs(self.expected)):
+            return self.nan_ok and math.isnan(abs(actual))
+
+        # Infinity shouldn't be approximately equal to anything but itself, but
+        # if there's a relative tolerance, it will be infinite and infinity
+        # will seem approximately equal to everything.  The equal-to-itself
+        # case would have been short circuited above, so here we can just
+        # return false if the expected value is infinite.  The abs() call is
+        # for compatibility with complex numbers.
+        if math.isinf(abs(self.expected)):
+            return False
+
+        # Return true if the two numbers are within the tolerance.
+        return abs(self.expected - actual) <= self.tolerance
+
+    __hash__ = None
+
+    @property
+    def tolerance(self):
+        """
+        Return the tolerance for the comparison.  This could be either an
+        absolute tolerance or a relative tolerance, depending on what the user
+        specified or which would be larger.
+        """
+
+        def set_default(x, default):
+            return x if x is not None else default
+
+        # Figure out what the absolute tolerance should be.  ``self.abs`` is
+        # either None or a value specified by the user.
+        absolute_tolerance = set_default(self.abs, self.DEFAULT_ABSOLUTE_TOLERANCE)
+
+        if absolute_tolerance < 0:
+            raise ValueError(
+                "absolute tolerance can't be negative: {}".format(absolute_tolerance)
+            )
+        if math.isnan(absolute_tolerance):
+            raise ValueError("absolute tolerance can't be NaN.")
+
+        # If the user specified an absolute tolerance but not a relative one,
+        # just return the absolute tolerance.
+        if self.rel is None:
+            if self.abs is not None:
+                return absolute_tolerance
+
+        # Figure out what the relative tolerance should be.  ``self.rel`` is
+        # either None or a value specified by the user.  This is done after
+        # we've made sure the user didn't ask for an absolute tolerance only,
+        # because we don't want to raise errors about the relative tolerance if
+        # we aren't even going to use it.
+        relative_tolerance = set_default(
+            self.rel, self.DEFAULT_RELATIVE_TOLERANCE
+        ) * abs(self.expected)
+
+        if relative_tolerance < 0:
+            raise ValueError(
+                "relative tolerance can't be negative: {}".format(absolute_tolerance)
+            )
+        if math.isnan(relative_tolerance):
+            raise ValueError("relative tolerance can't be NaN.")
+
+        # Return the larger of the relative and absolute tolerances.
+        return max(relative_tolerance, absolute_tolerance)
+
+
+class ApproxDecimal(ApproxScalar):
+    from decimal import Decimal
+
+    DEFAULT_ABSOLUTE_TOLERANCE = Decimal("1e-12")
+    DEFAULT_RELATIVE_TOLERANCE = Decimal("1e-6")
+
+
+def approx(expected, rel=None, abs=None, nan_ok=False):
+    """
+    Assert that two numbers (or two sets of numbers) are equal to each other
+    within some tolerance.
+
+    Due to the `intricacies of floating-point arithmetic`__, numbers that we
+    would intuitively expect to be equal are not always so::
+
+        >>> 0.1 + 0.2 == 0.3
+        False
+
+    __ https://docs.python.org/3/tutorial/floatingpoint.html
+
+    This problem is commonly encountered when writing tests, e.g. when making
+    sure that floating-point values are what you expect them to be.  One way to
+    deal with this problem is to assert that two floating-point numbers are
+    equal to within some appropriate tolerance::
+
+        >>> abs((0.1 + 0.2) - 0.3) < 1e-6
+        True
+
+    However, comparisons like this are tedious to write and difficult to
+    understand.  Furthermore, absolute comparisons like the one above are
+    usually discouraged because there's no tolerance that works well for all
+    situations.  ``1e-6`` is good for numbers around ``1``, but too small for
+    very big numbers and too big for very small ones.  It's better to express
+    the tolerance as a fraction of the expected value, but relative comparisons
+    like that are even more difficult to write correctly and concisely.
+
+    The ``approx`` class performs floating-point comparisons using a syntax
+    that's as intuitive as possible::
+
+        >>> from pytest import approx
+        >>> 0.1 + 0.2 == approx(0.3)
+        True
+
+    The same syntax also works for sequences of numbers::
+
+        >>> (0.1 + 0.2, 0.2 + 0.4) == approx((0.3, 0.6))
+        True
+
+    Dictionary *values*::
+
+        >>> {'a': 0.1 + 0.2, 'b': 0.2 + 0.4} == approx({'a': 0.3, 'b': 0.6})
+        True
+
+    ``numpy`` arrays::
+
+        >>> import numpy as np                                                          # doctest: +SKIP
+        >>> np.array([0.1, 0.2]) + np.array([0.2, 0.4]) == approx(np.array([0.3, 0.6])) # doctest: +SKIP
+        True
+
+    And for a ``numpy`` array against a scalar::
+
+        >>> import numpy as np                                         # doctest: +SKIP
+        >>> np.array([0.1, 0.2]) + np.array([0.2, 0.1]) == approx(0.3) # doctest: +SKIP
+        True
+
+    By default, ``approx`` considers numbers within a relative tolerance of
+    ``1e-6`` (i.e. one part in a million) of its expected value to be equal.
+    This treatment would lead to surprising results if the expected value was
+    ``0.0``, because nothing but ``0.0`` itself is relatively close to ``0.0``.
+    To handle this case less surprisingly, ``approx`` also considers numbers
+    within an absolute tolerance of ``1e-12`` of its expected value to be
+    equal.  Infinity and NaN are special cases.  Infinity is only considered
+    equal to itself, regardless of the relative tolerance.  NaN is not
+    considered equal to anything by default, but you can make it be equal to
+    itself by setting the ``nan_ok`` argument to True.  (This is meant to
+    facilitate comparing arrays that use NaN to mean "no data".)
+
+    Both the relative and absolute tolerances can be changed by passing
+    arguments to the ``approx`` constructor::
+
+        >>> 1.0001 == approx(1)
+        False
+        >>> 1.0001 == approx(1, rel=1e-3)
+        True
+        >>> 1.0001 == approx(1, abs=1e-3)
+        True
+
+    If you specify ``abs`` but not ``rel``, the comparison will not consider
+    the relative tolerance at all.  In other words, two numbers that are within
+    the default relative tolerance of ``1e-6`` will still be considered unequal
+    if they exceed the specified absolute tolerance.  If you specify both
+    ``abs`` and ``rel``, the numbers will be considered equal if either
+    tolerance is met::
+
+        >>> 1 + 1e-8 == approx(1)
+        True
+        >>> 1 + 1e-8 == approx(1, abs=1e-12)
+        False
+        >>> 1 + 1e-8 == approx(1, rel=1e-6, abs=1e-12)
+        True
+
+    If you're thinking about using ``approx``, then you might want to know how
+    it compares to other good ways of comparing floating-point numbers.  All of
+    these algorithms are based on relative and absolute tolerances and should
+    agree for the most part, but they do have meaningful differences:
+
+    - ``math.isclose(a, b, rel_tol=1e-9, abs_tol=0.0)``:  True if the relative
+      tolerance is met w.r.t. either ``a`` or ``b`` or if the absolute
+      tolerance is met.  Because the relative tolerance is calculated w.r.t.
+      both ``a`` and ``b``, this test is symmetric (i.e.  neither ``a`` nor
+      ``b`` is a "reference value").  You have to specify an absolute tolerance
+      if you want to compare to ``0.0`` because there is no tolerance by
+      default.  Only available in python>=3.5.  `More information...`__
+
+      __ https://docs.python.org/3/library/math.html#math.isclose
+
+    - ``numpy.isclose(a, b, rtol=1e-5, atol=1e-8)``: True if the difference
+      between ``a`` and ``b`` is less that the sum of the relative tolerance
+      w.r.t. ``b`` and the absolute tolerance.  Because the relative tolerance
+      is only calculated w.r.t. ``b``, this test is asymmetric and you can
+      think of ``b`` as the reference value.  Support for comparing sequences
+      is provided by ``numpy.allclose``.  `More information...`__
+
+      __ http://docs.scipy.org/doc/numpy-1.10.0/reference/generated/numpy.isclose.html
+
+    - ``unittest.TestCase.assertAlmostEqual(a, b)``: True if ``a`` and ``b``
+      are within an absolute tolerance of ``1e-7``.  No relative tolerance is
+      considered and the absolute tolerance cannot be changed, so this function
+      is not appropriate for very large or very small numbers.  Also, it's only
+      available in subclasses of ``unittest.TestCase`` and it's ugly because it
+      doesn't follow PEP8.  `More information...`__
+
+      __ https://docs.python.org/3/library/unittest.html#unittest.TestCase.assertAlmostEqual
+
+    - ``a == pytest.approx(b, rel=1e-6, abs=1e-12)``: True if the relative
+      tolerance is met w.r.t. ``b`` or if the absolute tolerance is met.
+      Because the relative tolerance is only calculated w.r.t. ``b``, this test
+      is asymmetric and you can think of ``b`` as the reference value.  In the
+      special case that you explicitly specify an absolute tolerance but not a
+      relative tolerance, only the absolute tolerance is considered.
+
+    .. warning::
+
+       .. versionchanged:: 3.2
+
+       In order to avoid inconsistent behavior, ``TypeError`` is
+       raised for ``>``, ``>=``, ``<`` and ``<=`` comparisons.
+       The example below illustrates the problem::
+
+           assert approx(0.1) > 0.1 + 1e-10  # calls approx(0.1).__gt__(0.1 + 1e-10)
+           assert 0.1 + 1e-10 > approx(0.1)  # calls approx(0.1).__lt__(0.1 + 1e-10)
+
+       In the second example one expects ``approx(0.1).__le__(0.1 + 1e-10)``
+       to be called. But instead, ``approx(0.1).__lt__(0.1 + 1e-10)`` is used to
+       comparison. This is because the call hierarchy of rich comparisons
+       follows a fixed behavior. `More information...`__
+
+       __ https://docs.python.org/3/reference/datamodel.html#object.__ge__
+    """
+
+    from decimal import Decimal
+
+    # Delegate the comparison to a class that knows how to deal with the type
+    # of the expected value (e.g. int, float, list, dict, numpy.array, etc).
+    #
+    # This architecture is really driven by the need to support numpy arrays.
+    # The only way to override `==` for arrays without requiring that approx be
+    # the left operand is to inherit the approx object from `numpy.ndarray`.
+    # But that can't be a general solution, because it requires (1) numpy to be
+    # installed and (2) the expected value to be a numpy array.  So the general
+    # solution is to delegate each type of expected value to a different class.
+    #
+    # This has the advantage that it made it easy to support mapping types
+    # (i.e. dict).  The old code accepted mapping types, but would only compare
+    # their keys, which is probably not what most people would expect.
+
+    if _is_numpy_array(expected):
+        cls = ApproxNumpy
+    elif isinstance(expected, Mapping):
+        cls = ApproxMapping
+    elif isinstance(expected, Sequence) and not isinstance(expected, STRING_TYPES):
+        cls = ApproxSequence
+    elif isinstance(expected, Decimal):
+        cls = ApproxDecimal
+    else:
+        cls = ApproxScalar
+
+    return cls(expected, rel, abs, nan_ok)
+
+
+def _is_numpy_array(obj):
+    """
+    Return true if the given object is a numpy array.  Make a special effort to
+    avoid importing numpy unless it's really necessary.
+    """
+    import inspect
+
+    for cls in inspect.getmro(type(obj)):
+        if cls.__module__ == "numpy":
+            try:
+                import numpy as np
+
+                return isinstance(obj, np.ndarray)
+            except ImportError:
+                pass
+
+    return False
+
+
+# builtin pytest.raises helper
+
+
+def raises(expected_exception, *args, **kwargs):
+    r"""
+    Assert that a code block/function call raises ``expected_exception``
+    and raise a failure exception otherwise.
+
+    :arg message: if specified, provides a custom failure message if the
+        exception is not raised
+    :arg match: if specified, asserts that the exception matches a text or regex
+
+    This helper produces a ``ExceptionInfo()`` object (see below).
+
+    You may use this function as a context manager::
+
+        >>> with raises(ZeroDivisionError):
+        ...    1/0
+
+    .. versionchanged:: 2.10
+
+    In the context manager form you may use the keyword argument
+    ``message`` to specify a custom failure message::
+
+        >>> with raises(ZeroDivisionError, message="Expecting ZeroDivisionError"):
+        ...    pass
+        Traceback (most recent call last):
+          ...
+        Failed: Expecting ZeroDivisionError
+
+    .. note::
+
+       When using ``pytest.raises`` as a context manager, it's worthwhile to
+       note that normal context manager rules apply and that the exception
+       raised *must* be the final line in the scope of the context manager.
+       Lines of code after that, within the scope of the context manager will
+       not be executed. For example::
+
+           >>> value = 15
+           >>> with raises(ValueError) as exc_info:
+           ...     if value > 10:
+           ...         raise ValueError("value must be <= 10")
+           ...     assert exc_info.type == ValueError  # this will not execute
+
+       Instead, the following approach must be taken (note the difference in
+       scope)::
+
+           >>> with raises(ValueError) as exc_info:
+           ...     if value > 10:
+           ...         raise ValueError("value must be <= 10")
+           ...
+           >>> assert exc_info.type == ValueError
+
+
+    Since version ``3.1`` you can use the keyword argument ``match`` to assert that the
+    exception matches a text or regex::
+
+        >>> with raises(ValueError, match='must be 0 or None'):
+        ...     raise ValueError("value must be 0 or None")
+
+        >>> with raises(ValueError, match=r'must be \d+$'):
+        ...     raise ValueError("value must be 42")
+
+    **Legacy forms**
+
+    The forms below are fully supported but are discouraged for new code because the
+    context manager form is regarded as more readable and less error-prone.
+
+    It is possible to specify a callable by passing a to-be-called lambda::
+
+        >>> raises(ZeroDivisionError, lambda: 1/0)
+        <ExceptionInfo ...>
+
+    or you can specify an arbitrary callable with arguments::
+
+        >>> def f(x): return 1/x
+        ...
+        >>> raises(ZeroDivisionError, f, 0)
+        <ExceptionInfo ...>
+        >>> raises(ZeroDivisionError, f, x=0)
+        <ExceptionInfo ...>
+
+    It is also possible to pass a string to be evaluated at runtime::
+
+        >>> raises(ZeroDivisionError, "f(0)")
+        <ExceptionInfo ...>
+
+    The string will be evaluated using the same ``locals()`` and ``globals()``
+    at the moment of the ``raises`` call.
+
+    .. currentmodule:: _pytest._code
+
+    Consult the API of ``excinfo`` objects: :class:`ExceptionInfo`.
+
+    .. note::
+        Similar to caught exception objects in Python, explicitly clearing
+        local references to returned ``ExceptionInfo`` objects can
+        help the Python interpreter speed up its garbage collection.
+
+        Clearing those references breaks a reference cycle
+        (``ExceptionInfo`` --> caught exception --> frame stack raising
+        the exception --> current frame stack --> local variables -->
+        ``ExceptionInfo``) which makes Python keep all objects referenced
+        from that cycle (including all local variables in the current
+        frame) alive until the next cyclic garbage collection run. See the
+        official Python ``try`` statement documentation for more detailed
+        information.
+
+    """
+    __tracebackhide__ = True
+    for exc in filterfalse(isclass, always_iterable(expected_exception, BASE_TYPE)):
+        msg = (
+            "exceptions must be old-style classes or"
+            " derived from BaseException, not %s"
+        )
+        raise TypeError(msg % type(exc))
+
+    message = "DID NOT RAISE {}".format(expected_exception)
+    match_expr = None
+
+    if not args:
+        if "message" in kwargs:
+            message = kwargs.pop("message")
+        if "match" in kwargs:
+            match_expr = kwargs.pop("match")
+        if kwargs:
+            msg = "Unexpected keyword arguments passed to pytest.raises: "
+            msg += ", ".join(kwargs.keys())
+            raise TypeError(msg)
+        return RaisesContext(expected_exception, message, match_expr)
+    elif isinstance(args[0], str):
+        code, = args
+        assert isinstance(code, str)
+        frame = sys._getframe(1)
+        loc = frame.f_locals.copy()
+        loc.update(kwargs)
+        # print "raises frame scope: %r" % frame.f_locals
+        try:
+            code = _pytest._code.Source(code).compile()
+            py.builtin.exec_(code, frame.f_globals, loc)
+            # XXX didn'T mean f_globals == f_locals something special?
+            #     this is destroyed here ...
+        except expected_exception:
+            return _pytest._code.ExceptionInfo()
+    else:
+        func = args[0]
+        try:
+            func(*args[1:], **kwargs)
+        except expected_exception:
+            return _pytest._code.ExceptionInfo()
+    fail(message)
+
+
+raises.Exception = fail.Exception
+
+
+class RaisesContext(object):
+    def __init__(self, expected_exception, message, match_expr):
+        self.expected_exception = expected_exception
+        self.message = message
+        self.match_expr = match_expr
+        self.excinfo = None
+
+    def __enter__(self):
+        self.excinfo = object.__new__(_pytest._code.ExceptionInfo)
+        return self.excinfo
+
+    def __exit__(self, *tp):
+        __tracebackhide__ = True
+        if tp[0] is None:
+            fail(self.message)
+        self.excinfo.__init__(tp)
+        suppress_exception = issubclass(self.excinfo.type, self.expected_exception)
+        if sys.version_info[0] == 2 and suppress_exception:
+            sys.exc_clear()
+        if self.match_expr and suppress_exception:
+            self.excinfo.match(self.match_expr)
+        return suppress_exception

src/_pytest/recwarn.py

@@ -0,0 +1,240 @@
+""" recording warnings during test function execution. """
+from __future__ import absolute_import, division, print_function
+
+import inspect
+
+import _pytest._code
+import py
+import sys
+import warnings
+
+import re
+
+from _pytest.fixtures import yield_fixture
+from _pytest.outcomes import fail
+
+
+@yield_fixture
+def recwarn():
+    """Return a :class:`WarningsRecorder` instance that records all warnings emitted by test functions.
+
+    See http://docs.python.org/library/warnings.html for information
+    on warning categories.
+    """
+    wrec = WarningsRecorder()
+    with wrec:
+        warnings.simplefilter("default")
+        yield wrec
+
+
+def deprecated_call(func=None, *args, **kwargs):
+    """context manager that can be used to ensure a block of code triggers a
+    ``DeprecationWarning`` or ``PendingDeprecationWarning``::
+
+        >>> import warnings
+        >>> def api_call_v2():
+        ...     warnings.warn('use v3 of this api', DeprecationWarning)
+        ...     return 200
+
+        >>> with deprecated_call():
+        ...    assert api_call_v2() == 200
+
+    ``deprecated_call`` can also be used by passing a function and ``*args`` and ``*kwargs``,
+    in which case it will ensure calling ``func(*args, **kwargs)`` produces one of the warnings
+    types above.
+    """
+    if not func:
+        return _DeprecatedCallContext()
+    else:
+        __tracebackhide__ = True
+        with _DeprecatedCallContext():
+            return func(*args, **kwargs)
+
+
+class _DeprecatedCallContext(object):
+    """Implements the logic to capture deprecation warnings as a context manager."""
+
+    def __enter__(self):
+        self._captured_categories = []
+        self._old_warn = warnings.warn
+        self._old_warn_explicit = warnings.warn_explicit
+        warnings.warn_explicit = self._warn_explicit
+        warnings.warn = self._warn
+
+    def _warn_explicit(self, message, category, *args, **kwargs):
+        self._captured_categories.append(category)
+
+    def _warn(self, message, category=None, *args, **kwargs):
+        if isinstance(message, Warning):
+            self._captured_categories.append(message.__class__)
+        else:
+            self._captured_categories.append(category)
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        warnings.warn_explicit = self._old_warn_explicit
+        warnings.warn = self._old_warn
+
+        if exc_type is None:
+            deprecation_categories = (DeprecationWarning, PendingDeprecationWarning)
+            if not any(
+                issubclass(c, deprecation_categories) for c in self._captured_categories
+            ):
+                __tracebackhide__ = True
+                msg = "Did not produce DeprecationWarning or PendingDeprecationWarning"
+                raise AssertionError(msg)
+
+
+def warns(expected_warning, *args, **kwargs):
+    r"""Assert that code raises a particular class of warning.
+
+    Specifically, the parameter ``expected_warning`` can be a warning class or
+    sequence of warning classes, and the inside the ``with`` block must issue a warning of that class or
+    classes.
+
+    This helper produces a list of :class:`warnings.WarningMessage` objects,
+    one for each warning raised.
+
+    This function can be used as a context manager, or any of the other ways
+    ``pytest.raises`` can be used::
+
+        >>> with warns(RuntimeWarning):
+        ...    warnings.warn("my warning", RuntimeWarning)
+
+    In the context manager form you may use the keyword argument ``match`` to assert
+    that the exception matches a text or regex::
+
+        >>> with warns(UserWarning, match='must be 0 or None'):
+        ...     warnings.warn("value must be 0 or None", UserWarning)
+
+        >>> with warns(UserWarning, match=r'must be \d+$'):
+        ...     warnings.warn("value must be 42", UserWarning)
+
+        >>> with warns(UserWarning, match=r'must be \d+$'):
+        ...     warnings.warn("this is not here", UserWarning)
+        Traceback (most recent call last):
+          ...
+        Failed: DID NOT WARN. No warnings of type ...UserWarning... was emitted...
+
+    """
+    match_expr = None
+    if not args:
+        if "match" in kwargs:
+            match_expr = kwargs.pop("match")
+        return WarningsChecker(expected_warning, match_expr=match_expr)
+    elif isinstance(args[0], str):
+        code, = args
+        assert isinstance(code, str)
+        frame = sys._getframe(1)
+        loc = frame.f_locals.copy()
+        loc.update(kwargs)
+
+        with WarningsChecker(expected_warning, match_expr=match_expr):
+            code = _pytest._code.Source(code).compile()
+            py.builtin.exec_(code, frame.f_globals, loc)
+    else:
+        func = args[0]
+        with WarningsChecker(expected_warning, match_expr=match_expr):
+            return func(*args[1:], **kwargs)
+
+
+class WarningsRecorder(warnings.catch_warnings):
+    """A context manager to record raised warnings.
+
+    Adapted from `warnings.catch_warnings`.
+    """
+
+    def __init__(self):
+        super(WarningsRecorder, self).__init__(record=True)
+        self._entered = False
+        self._list = []
+
+    @property
+    def list(self):
+        """The list of recorded warnings."""
+        return self._list
+
+    def __getitem__(self, i):
+        """Get a recorded warning by index."""
+        return self._list[i]
+
+    def __iter__(self):
+        """Iterate through the recorded warnings."""
+        return iter(self._list)
+
+    def __len__(self):
+        """The number of recorded warnings."""
+        return len(self._list)
+
+    def pop(self, cls=Warning):
+        """Pop the first recorded warning, raise exception if not exists."""
+        for i, w in enumerate(self._list):
+            if issubclass(w.category, cls):
+                return self._list.pop(i)
+        __tracebackhide__ = True
+        raise AssertionError("%r not found in warning list" % cls)
+
+    def clear(self):
+        """Clear the list of recorded warnings."""
+        self._list[:] = []
+
+    def __enter__(self):
+        if self._entered:
+            __tracebackhide__ = True
+            raise RuntimeError("Cannot enter %r twice" % self)
+        self._list = super(WarningsRecorder, self).__enter__()
+        warnings.simplefilter("always")
+        return self
+
+    def __exit__(self, *exc_info):
+        if not self._entered:
+            __tracebackhide__ = True
+            raise RuntimeError("Cannot exit %r without entering first" % self)
+        super(WarningsRecorder, self).__exit__(*exc_info)
+
+
+class WarningsChecker(WarningsRecorder):
+    def __init__(self, expected_warning=None, match_expr=None):
+        super(WarningsChecker, self).__init__()
+
+        msg = "exceptions must be old-style classes or " "derived from Warning, not %s"
+        if isinstance(expected_warning, tuple):
+            for exc in expected_warning:
+                if not inspect.isclass(exc):
+                    raise TypeError(msg % type(exc))
+        elif inspect.isclass(expected_warning):
+            expected_warning = (expected_warning,)
+        elif expected_warning is not None:
+            raise TypeError(msg % type(expected_warning))
+
+        self.expected_warning = expected_warning
+        self.match_expr = match_expr
+
+    def __exit__(self, *exc_info):
+        super(WarningsChecker, self).__exit__(*exc_info)
+
+        # only check if we're not currently handling an exception
+        if all(a is None for a in exc_info):
+            if self.expected_warning is not None:
+                if not any(issubclass(r.category, self.expected_warning) for r in self):
+                    __tracebackhide__ = True
+                    fail(
+                        "DID NOT WARN. No warnings of type {} was emitted. "
+                        "The list of emitted warnings is: {}.".format(
+                            self.expected_warning, [each.message for each in self]
+                        )
+                    )
+                elif self.match_expr is not None:
+                    for r in self:
+                        if issubclass(r.category, self.expected_warning):
+                            if re.compile(self.match_expr).search(str(r.message)):
+                                break
+                    else:
+                        fail(
+                            "DID NOT WARN. No warnings of type {} matching"
+                            " ('{}') was emitted. The list of emitted warnings"
+                            " is: {}.".format(
+                                self.expected_warning,
+                                self.match_expr,
+                                [each.message for each in self],
+                            )
+                        )

src/_pytest/reports.py

@@ -0,0 +1,196 @@
+import py
+from _pytest._code.code import TerminalRepr
+
+
+def getslaveinfoline(node):
+    try:
+        return node._slaveinfocache
+    except AttributeError:
+        d = node.slaveinfo
+        ver = "%s.%s.%s" % d["version_info"][:3]
+        node._slaveinfocache = s = "[%s] %s -- Python %s %s" % (
+            d["id"],
+            d["sysplatform"],
+            ver,
+            d["executable"],
+        )
+        return s
+
+
+class BaseReport(object):
+    def __init__(self, **kw):
+        self.__dict__.update(kw)
+
+    def toterminal(self, out):
+        if hasattr(self, "node"):
+            out.line(getslaveinfoline(self.node))
+
+        longrepr = self.longrepr
+        if longrepr is None:
+            return
+
+        if hasattr(longrepr, "toterminal"):
+            longrepr.toterminal(out)
+        else:
+            try:
+                out.line(longrepr)
+            except UnicodeEncodeError:
+                out.line("<unprintable longrepr>")
+
+    def get_sections(self, prefix):
+        for name, content in self.sections:
+            if name.startswith(prefix):
+                yield prefix, content
+
+    @property
+    def longreprtext(self):
+        """
+        Read-only property that returns the full string representation
+        of ``longrepr``.
+
+        .. versionadded:: 3.0
+        """
+        tw = py.io.TerminalWriter(stringio=True)
+        tw.hasmarkup = False
+        self.toterminal(tw)
+        exc = tw.stringio.getvalue()
+        return exc.strip()
+
+    @property
+    def caplog(self):
+        """Return captured log lines, if log capturing is enabled
+
+        .. versionadded:: 3.5
+        """
+        return "\n".join(
+            content for (prefix, content) in self.get_sections("Captured log")
+        )
+
+    @property
+    def capstdout(self):
+        """Return captured text from stdout, if capturing is enabled
+
+        .. versionadded:: 3.0
+        """
+        return "".join(
+            content for (prefix, content) in self.get_sections("Captured stdout")
+        )
+
+    @property
+    def capstderr(self):
+        """Return captured text from stderr, if capturing is enabled
+
+        .. versionadded:: 3.0
+        """
+        return "".join(
+            content for (prefix, content) in self.get_sections("Captured stderr")
+        )
+
+    passed = property(lambda x: x.outcome == "passed")
+    failed = property(lambda x: x.outcome == "failed")
+    skipped = property(lambda x: x.outcome == "skipped")
+
+    @property
+    def fspath(self):
+        return self.nodeid.split("::")[0]
+
+
+class TestReport(BaseReport):
+    """ Basic test report object (also used for setup and teardown calls if
+    they fail).
+    """
+
+    def __init__(
+        self,
+        nodeid,
+        location,
+        keywords,
+        outcome,
+        longrepr,
+        when,
+        sections=(),
+        duration=0,
+        user_properties=(),
+        **extra
+    ):
+        #: normalized collection node id
+        self.nodeid = nodeid
+
+        #: a (filesystempath, lineno, domaininfo) tuple indicating the
+        #: actual location of a test item - it might be different from the
+        #: collected one e.g. if a method is inherited from a different module.
+        self.location = location
+
+        #: a name -> value dictionary containing all keywords and
+        #: markers associated with a test invocation.
+        self.keywords = keywords
+
+        #: test outcome, always one of "passed", "failed", "skipped".
+        self.outcome = outcome
+
+        #: None or a failure representation.
+        self.longrepr = longrepr
+
+        #: one of 'setup', 'call', 'teardown' to indicate runtest phase.
+        self.when = when
+
+        #: user properties is a list of tuples (name, value) that holds user
+        #: defined properties of the test
+        self.user_properties = user_properties
+
+        #: list of pairs ``(str, str)`` of extra information which needs to
+        #: marshallable. Used by pytest to add captured text
+        #: from ``stdout`` and ``stderr``, but may be used by other plugins
+        #: to add arbitrary information to reports.
+        self.sections = list(sections)
+
+        #: time it took to run just the test
+        self.duration = duration
+
+        self.__dict__.update(extra)
+
+    def __repr__(self):
+        return "<TestReport %r when=%r outcome=%r>" % (
+            self.nodeid,
+            self.when,
+            self.outcome,
+        )
+
+
+class TeardownErrorReport(BaseReport):
+    outcome = "failed"
+    when = "teardown"
+
+    def __init__(self, longrepr, **extra):
+        self.longrepr = longrepr
+        self.sections = []
+        self.__dict__.update(extra)
+
+
+class CollectReport(BaseReport):
+    def __init__(self, nodeid, outcome, longrepr, result, sections=(), **extra):
+        self.nodeid = nodeid
+        self.outcome = outcome
+        self.longrepr = longrepr
+        self.result = result or []
+        self.sections = list(sections)
+        self.__dict__.update(extra)
+
+    @property
+    def location(self):
+        return (self.fspath, None, self.fspath)
+
+    def __repr__(self):
+        return "<CollectReport %r lenresult=%s outcome=%r>" % (
+            self.nodeid,
+            len(self.result),
+            self.outcome,
+        )
+
+
+class CollectErrorRepr(TerminalRepr):
+    def __init__(self, msg):
+        self.longrepr = msg
+
+    def toterminal(self, out):
+        out.line(self.longrepr, red=True)

src/_pytest/resultlog.py

@@ -0,0 +1,119 @@
+""" log machine-parseable test session result information in a plain
+text file.
+"""
+from __future__ import absolute_import, division, print_function
+
+import py
+import os
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("terminal reporting", "resultlog plugin options")
+    group.addoption(
+        "--resultlog",
+        "--result-log",
+        action="store",
+        metavar="path",
+        default=None,
+        help="DEPRECATED path for machine-readable result log.",
+    )
+
+
+def pytest_configure(config):
+    resultlog = config.option.resultlog
+    # prevent opening resultlog on slave nodes (xdist)
+    if resultlog and not hasattr(config, "slaveinput"):
+        dirname = os.path.dirname(os.path.abspath(resultlog))
+        if not os.path.isdir(dirname):
+            os.makedirs(dirname)
+        logfile = open(resultlog, "w", 1)  # line buffered
+        config._resultlog = ResultLog(config, logfile)
+        config.pluginmanager.register(config._resultlog)
+
+        from _pytest.deprecated import RESULT_LOG
+
+        config.warn("C1", RESULT_LOG)
+
+
+def pytest_unconfigure(config):
+    resultlog = getattr(config, "_resultlog", None)
+    if resultlog:
+        resultlog.logfile.close()
+        del config._resultlog
+        config.pluginmanager.unregister(resultlog)
+
+
+def generic_path(item):
+    chain = item.listchain()
+    gpath = [chain[0].name]
+    fspath = chain[0].fspath
+    fspart = False
+    for node in chain[1:]:
+        newfspath = node.fspath
+        if newfspath == fspath:
+            if fspart:
+                gpath.append(":")
+                fspart = False
+            else:
+                gpath.append(".")
+        else:
+            gpath.append("/")
+            fspart = True
+        name = node.name
+        if name[0] in "([":
+            gpath.pop()
+        gpath.append(name)
+        fspath = newfspath
+    return "".join(gpath)
+
+
+class ResultLog(object):
+    def __init__(self, config, logfile):
+        self.config = config
+        self.logfile = logfile  # preferably line buffered
+
+    def write_log_entry(self, testpath, lettercode, longrepr):
+        print("%s %s" % (lettercode, testpath), file=self.logfile)
+        for line in longrepr.splitlines():
+            print(" %s" % line, file=self.logfile)
+
+    def log_outcome(self, report, lettercode, longrepr):
+        testpath = getattr(report, "nodeid", None)
+        if testpath is None:
+            testpath = report.fspath
+        self.write_log_entry(testpath, lettercode, longrepr)
+
+    def pytest_runtest_logreport(self, report):
+        if report.when != "call" and report.passed:
+            return
+        res = self.config.hook.pytest_report_teststatus(report=report)
+        code = res[1]
+        if code == "x":
+            longrepr = str(report.longrepr)
+        elif code == "X":
+            longrepr = ""
+        elif report.passed:
+            longrepr = ""
+        elif report.failed:
+            longrepr = str(report.longrepr)
+        elif report.skipped:
+            longrepr = str(report.longrepr[2])
+        self.log_outcome(report, code, longrepr)
+
+    def pytest_collectreport(self, report):
+        if not report.passed:
+            if report.failed:
+                code = "F"
+                longrepr = str(report.longrepr)
+            else:
+                assert report.skipped
+                code = "S"
+                longrepr = "%s:%d: %s" % report.longrepr
+            self.log_outcome(report, code, longrepr)
+
+    def pytest_internalerror(self, excrepr):
+        reprcrash = getattr(excrepr, "reprcrash", None)
+        path = getattr(reprcrash, "path", None)
+        if path is None:
+            path = "cwd:%s" % py.path.local()
+        self.write_log_entry(path, "!", str(excrepr))

src/_pytest/runner.py

@@ -0,0 +1,383 @@
+""" basic collect and runtest protocol implementations """
+from __future__ import absolute_import, division, print_function
+
+import bdb
+import os
+import sys
+from time import time
+
+import py
+from _pytest._code.code import ExceptionInfo
+from _pytest.outcomes import skip, Skipped, TEST_OUTCOME
+
+from .reports import TestReport, CollectReport, CollectErrorRepr
+
+#
+# pytest plugin hooks
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("terminal reporting", "reporting", after="general")
+    group.addoption(
+        "--durations",
+        action="store",
+        type=int,
+        default=None,
+        metavar="N",
+        help="show N slowest setup/test durations (N=0 for all).",
+    ),
+
+
+def pytest_terminal_summary(terminalreporter):
+    durations = terminalreporter.config.option.durations
+    if durations is None:
+        return
+    tr = terminalreporter
+    dlist = []
+    for replist in tr.stats.values():
+        for rep in replist:
+            if hasattr(rep, "duration"):
+                dlist.append(rep)
+    if not dlist:
+        return
+    dlist.sort(key=lambda x: x.duration)
+    dlist.reverse()
+    if not durations:
+        tr.write_sep("=", "slowest test durations")
+    else:
+        tr.write_sep("=", "slowest %s test durations" % durations)
+        dlist = dlist[:durations]
+
+    for rep in dlist:
+        nodeid = rep.nodeid.replace("::()::", "::")
+        tr.write_line("%02.2fs %-8s %s" % (rep.duration, rep.when, nodeid))
+
+
+def pytest_sessionstart(session):
+    session._setupstate = SetupState()
+
+
+def pytest_sessionfinish(session):
+    session._setupstate.teardown_all()
+
+
+def pytest_runtest_protocol(item, nextitem):
+    item.ihook.pytest_runtest_logstart(nodeid=item.nodeid, location=item.location)
+    runtestprotocol(item, nextitem=nextitem)
+    item.ihook.pytest_runtest_logfinish(nodeid=item.nodeid, location=item.location)
+    return True
+
+
+def runtestprotocol(item, log=True, nextitem=None):
+    hasrequest = hasattr(item, "_request")
+    if hasrequest and not item._request:
+        item._initrequest()
+    rep = call_and_report(item, "setup", log)
+    reports = [rep]
+    if rep.passed:
+        if item.config.option.setupshow:
+            show_test_item(item)
+        if not item.config.option.setuponly:
+            reports.append(call_and_report(item, "call", log))
+    reports.append(call_and_report(item, "teardown", log, nextitem=nextitem))
+    # after all teardown hooks have been called
+    # want funcargs and request info to go away
+    if hasrequest:
+        item._request = False
+        item.funcargs = None
+    return reports
+
+
+def show_test_item(item):
+    """Show test function, parameters and the fixtures of the test item."""
+    tw = item.config.get_terminal_writer()
+    tw.line()
+    tw.write(" " * 8)
+    tw.write(item._nodeid)
+    used_fixtures = sorted(item._fixtureinfo.name2fixturedefs.keys())
+    if used_fixtures:
+        tw.write(" (fixtures used: {})".format(", ".join(used_fixtures)))
+
+
+def pytest_runtest_setup(item):
+    _update_current_test_var(item, "setup")
+    item.session._setupstate.prepare(item)
+
+
+def pytest_runtest_call(item):
+    _update_current_test_var(item, "call")
+    sys.last_type, sys.last_value, sys.last_traceback = (None, None, None)
+    try:
+        item.runtest()
+    except Exception:
+        # Store trace info to allow postmortem debugging
+        type, value, tb = sys.exc_info()
+        tb = tb.tb_next  # Skip *this* frame
+        sys.last_type = type
+        sys.last_value = value
+        sys.last_traceback = tb
+        del type, value, tb  # Get rid of these in this frame
+        raise
+
+
+def pytest_runtest_teardown(item, nextitem):
+    _update_current_test_var(item, "teardown")
+    item.session._setupstate.teardown_exact(item, nextitem)
+    _update_current_test_var(item, None)
+
+
+def _update_current_test_var(item, when):
+    """
+    Update PYTEST_CURRENT_TEST to reflect the current item and stage.
+
+    If ``when`` is None, delete PYTEST_CURRENT_TEST from the environment.
+    """
+    var_name = "PYTEST_CURRENT_TEST"
+    if when:
+        value = "{} ({})".format(item.nodeid, when)
+        # don't allow null bytes on environment variables (see #2644, #2957)
+        value = value.replace("\x00", "(null)")
+        os.environ[var_name] = value
+    else:
+        os.environ.pop(var_name)
+
+
+def pytest_report_teststatus(report):
+    if report.when in ("setup", "teardown"):
+        if report.failed:
+            #      category, shortletter, verbose-word
+            return "error", "E", "ERROR"
+        elif report.skipped:
+            return "skipped", "s", "SKIPPED"
+        else:
+            return "", "", ""
+
+
+#
+# Implementation
+
+
+def call_and_report(item, when, log=True, **kwds):
+    call = call_runtest_hook(item, when, **kwds)
+    hook = item.ihook
+    report = hook.pytest_runtest_makereport(item=item, call=call)
+    if log:
+        hook.pytest_runtest_logreport(report=report)
+    if check_interactive_exception(call, report):
+        hook.pytest_exception_interact(node=item, call=call, report=report)
+    return report
+
+
+def check_interactive_exception(call, report):
+    return call.excinfo and not (
+        hasattr(report, "wasxfail")
+        or call.excinfo.errisinstance(skip.Exception)
+        or call.excinfo.errisinstance(bdb.BdbQuit)
+    )
+
+
+def call_runtest_hook(item, when, **kwds):
+    hookname = "pytest_runtest_" + when
+    ihook = getattr(item.ihook, hookname)
+    return CallInfo(
+        lambda: ihook(item=item, **kwds),
+        when=when,
+        treat_keyboard_interrupt_as_exception=item.config.getvalue("usepdb"),
+    )
+
+
+class CallInfo(object):
+    """ Result/Exception info a function invocation. """
+
+    #: None or ExceptionInfo object.
+    excinfo = None
+
+    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
+        #: context of invocation: one of "setup", "call",
+        #: "teardown", "memocollect"
+        self.when = when
+        self.start = time()
+        try:
+            self.result = func()
+        except KeyboardInterrupt:
+            if treat_keyboard_interrupt_as_exception:
+                self.excinfo = ExceptionInfo()
+            else:
+                self.stop = time()
+                raise
+        except:  # noqa
+            self.excinfo = ExceptionInfo()
+        self.stop = time()
+
+    def __repr__(self):
+        if self.excinfo:
+            status = "exception: %s" % str(self.excinfo.value)
+        else:
+            status = "result: %r" % (self.result,)
+        return "<CallInfo when=%r %s>" % (self.when, status)
+
+
+def pytest_runtest_makereport(item, call):
+    when = call.when
+    duration = call.stop - call.start
+    keywords = {x: 1 for x in item.keywords}
+    excinfo = call.excinfo
+    sections = []
+    if not call.excinfo:
+        outcome = "passed"
+        longrepr = None
+    else:
+        if not isinstance(excinfo, ExceptionInfo):
+            outcome = "failed"
+            longrepr = excinfo
+        elif excinfo.errisinstance(skip.Exception):
+            outcome = "skipped"
+            r = excinfo._getreprcrash()
+            longrepr = (str(r.path), r.lineno, r.message)
+        else:
+            outcome = "failed"
+            if call.when == "call":
+                longrepr = item.repr_failure(excinfo)
+            else:  # exception in setup or teardown
+                longrepr = item._repr_failure_py(
+                    excinfo, style=item.config.option.tbstyle
+                )
+    for rwhen, key, content in item._report_sections:
+        sections.append(("Captured %s %s" % (key, rwhen), content))
+    return TestReport(
+        item.nodeid,
+        item.location,
+        keywords,
+        outcome,
+        longrepr,
+        when,
+        sections,
+        duration,
+        user_properties=item.user_properties,
+    )
+
+
+def pytest_make_collect_report(collector):
+    call = CallInfo(lambda: list(collector.collect()), "collect")
+    longrepr = None
+    if not call.excinfo:
+        outcome = "passed"
+    else:
+        from _pytest import nose
+
+        skip_exceptions = (Skipped,) + nose.get_skip_exceptions()
+        if call.excinfo.errisinstance(skip_exceptions):
+            outcome = "skipped"
+            r = collector._repr_failure_py(call.excinfo, "line").reprcrash
+            longrepr = (str(r.path), r.lineno, r.message)
+        else:
+            outcome = "failed"
+            errorinfo = collector.repr_failure(call.excinfo)
+            if not hasattr(errorinfo, "toterminal"):
+                errorinfo = CollectErrorRepr(errorinfo)
+            longrepr = errorinfo
+    rep = CollectReport(
+        collector.nodeid, outcome, longrepr, getattr(call, "result", None)
+    )
+    rep.call = call  # see collect_one_node
+    return rep
+
+
+class SetupState(object):
+    """ shared state for setting up/tearing down test items or collectors. """
+
+    def __init__(self):
+        self.stack = []
+        self._finalizers = {}
+
+    def addfinalizer(self, finalizer, colitem):
+        """ attach a finalizer to the given colitem.
+        if colitem is None, this will add a finalizer that
+        is called at the end of teardown_all().
+        """
+        assert colitem and not isinstance(colitem, tuple)
+        assert callable(finalizer)
+        # assert colitem in self.stack  # some unit tests don't setup stack :/
+        self._finalizers.setdefault(colitem, []).append(finalizer)
+
+    def _pop_and_teardown(self):
+        colitem = self.stack.pop()
+        self._teardown_with_finalization(colitem)
+
+    def _callfinalizers(self, colitem):
+        finalizers = self._finalizers.pop(colitem, None)
+        exc = None
+        while finalizers:
+            fin = finalizers.pop()
+            try:
+                fin()
+            except TEST_OUTCOME:
+                # XXX Only first exception will be seen by user,
+                #     ideally all should be reported.
+                if exc is None:
+                    exc = sys.exc_info()
+        if exc:
+            py.builtin._reraise(*exc)
+
+    def _teardown_with_finalization(self, colitem):
+        self._callfinalizers(colitem)
+        if hasattr(colitem, "teardown"):
+            colitem.teardown()
+        for colitem in self._finalizers:
+            assert (
+                colitem is None or colitem in self.stack or isinstance(colitem, tuple)
+            )
+
+    def teardown_all(self):
+        while self.stack:
+            self._pop_and_teardown()
+        for key in list(self._finalizers):
+            self._teardown_with_finalization(key)
+        assert not self._finalizers
+
+    def teardown_exact(self, item, nextitem):
+        needed_collectors = nextitem and nextitem.listchain() or []
+        self._teardown_towards(needed_collectors)
+
+    def _teardown_towards(self, needed_collectors):
+        exc = None
+        while self.stack:
+            if self.stack == needed_collectors[: len(self.stack)]:
+                break
+            try:
+                self._pop_and_teardown()
+            except TEST_OUTCOME:
+                # XXX Only first exception will be seen by user,
+                #     ideally all should be reported.
+                if exc is None:
+                    exc = sys.exc_info()
+        if exc:
+            py.builtin._reraise(*exc)
+
+    def prepare(self, colitem):
+        """ setup objects along the collector chain to the test-method
+            and teardown previously setup objects."""
+        needed_collectors = colitem.listchain()
+        self._teardown_towards(needed_collectors)
+
+        # check if the last collection node has raised an error
+        for col in self.stack:
+            if hasattr(col, "_prepare_exc"):
+                py.builtin._reraise(*col._prepare_exc)
+        for col in needed_collectors[len(self.stack) :]:
+            self.stack.append(col)
+            try:
+                col.setup()
+            except TEST_OUTCOME:
+                col._prepare_exc = sys.exc_info()
+                raise
+
+
+def collect_one_node(collector):
+    ihook = collector.ihook
+    ihook.pytest_collectstart(collector=collector)
+    rep = ihook.pytest_make_collect_report(collector=collector)
+    call = rep.__dict__.pop("call", None)
+    if call and check_interactive_exception(call, rep):
+        ihook.pytest_exception_interact(node=collector, call=call, report=rep)
+    return rep

src/_pytest/setuponly.py

@@ -0,0 +1,84 @@
+from __future__ import absolute_import, division, print_function
+
+import pytest
+import sys
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("debugconfig")
+    group.addoption(
+        "--setuponly",
+        "--setup-only",
+        action="store_true",
+        help="only setup fixtures, do not execute tests.",
+    )
+    group.addoption(
+        "--setupshow",
+        "--setup-show",
+        action="store_true",
+        help="show setup of fixtures while executing tests.",
+    )
+
+
+@pytest.hookimpl(hookwrapper=True)
+def pytest_fixture_setup(fixturedef, request):
+    yield
+    config = request.config
+    if config.option.setupshow:
+        if hasattr(request, "param"):
+            # Save the fixture parameter so ._show_fixture_action() can
+            # display it now and during the teardown (in .finish()).
+            if fixturedef.ids:
+                if callable(fixturedef.ids):
+                    fixturedef.cached_param = fixturedef.ids(request.param)
+                else:
+                    fixturedef.cached_param = fixturedef.ids[request.param_index]
+            else:
+                fixturedef.cached_param = request.param
+        _show_fixture_action(fixturedef, "SETUP")
+
+
+def pytest_fixture_post_finalizer(fixturedef):
+    if hasattr(fixturedef, "cached_result"):
+        config = fixturedef._fixturemanager.config
+        if config.option.setupshow:
+            _show_fixture_action(fixturedef, "TEARDOWN")
+            if hasattr(fixturedef, "cached_param"):
+                del fixturedef.cached_param
+
+
+def _show_fixture_action(fixturedef, msg):
+    config = fixturedef._fixturemanager.config
+    capman = config.pluginmanager.getplugin("capturemanager")
+    if capman:
+        out, err = capman.suspend_global_capture()
+
+    tw = config.get_terminal_writer()
+    tw.line()
+    tw.write(" " * 2 * fixturedef.scopenum)
+    tw.write(
+        "{step} {scope} {fixture}".format(
+            step=msg.ljust(8),  # align the output to TEARDOWN
+            scope=fixturedef.scope[0].upper(),
+            fixture=fixturedef.argname,
+        )
+    )
+
+    if msg == "SETUP":
+        deps = sorted(arg for arg in fixturedef.argnames if arg != "request")
+        if deps:
+            tw.write(" (fixtures used: {})".format(", ".join(deps)))
+
+    if hasattr(fixturedef, "cached_param"):
+        tw.write("[{}]".format(fixturedef.cached_param))
+
+    if capman:
+        capman.resume_global_capture()
+        sys.stdout.write(out)
+        sys.stderr.write(err)
+
+
+@pytest.hookimpl(tryfirst=True)
+def pytest_cmdline_main(config):
+    if config.option.setuponly:
+        config.option.setupshow = True

src/_pytest/setupplan.py

@@ -0,0 +1,29 @@
+from __future__ import absolute_import, division, print_function
+
+import pytest
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("debugconfig")
+    group.addoption(
+        "--setupplan",
+        "--setup-plan",
+        action="store_true",
+        help="show what fixtures and tests would be executed but "
+        "don't execute anything.",
+    )
+
+
+@pytest.hookimpl(tryfirst=True)
+def pytest_fixture_setup(fixturedef, request):
+    # Will return a dummy fixture if the setuponly option is provided.
+    if request.config.option.setupplan:
+        fixturedef.cached_result = (None, None, None)
+        return fixturedef.cached_result
+
+
+@pytest.hookimpl(tryfirst=True)
+def pytest_cmdline_main(config):
+    if config.option.setupplan:
+        config.option.setuponly = True
+        config.option.setupshow = True

src/_pytest/skipping.py

@@ -0,0 +1,294 @@
+""" support for skip/xfail functions and markers. """
+from __future__ import absolute_import, division, print_function
+
+from _pytest.config import hookimpl
+from _pytest.mark.evaluate import MarkEvaluator
+from _pytest.outcomes import fail, skip, xfail
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("general")
+    group.addoption(
+        "--runxfail",
+        action="store_true",
+        dest="runxfail",
+        default=False,
+        help="run tests even if they are marked xfail",
+    )
+
+    parser.addini(
+        "xfail_strict",
+        "default for the strict parameter of xfail "
+        "markers when not given explicitly (default: False)",
+        default=False,
+        type="bool",
+    )
+
+
+def pytest_configure(config):
+    if config.option.runxfail:
+        # yay a hack
+        import pytest
+
+        old = pytest.xfail
+        config._cleanup.append(lambda: setattr(pytest, "xfail", old))
+
+        def nop(*args, **kwargs):
+            pass
+
+        nop.Exception = xfail.Exception
+        setattr(pytest, "xfail", nop)
+
+    config.addinivalue_line(
+        "markers",
+        "skip(reason=None): skip the given test function with an optional reason. "
+        'Example: skip(reason="no way of currently testing this") skips the '
+        "test.",
+    )
+    config.addinivalue_line(
+        "markers",
+        "skipif(condition): skip the given test function if eval(condition) "
+        "results in a True value.  Evaluation happens within the "
+        "module global context. Example: skipif('sys.platform == \"win32\"') "
+        "skips the test if we are on the win32 platform. see "
+        "http://pytest.org/latest/skipping.html",
+    )
+    config.addinivalue_line(
+        "markers",
+        "xfail(condition, reason=None, run=True, raises=None, strict=False): "
+        "mark the test function as an expected failure if eval(condition) "
+        "has a True value. Optionally specify a reason for better reporting "
+        "and run=False if you don't even want to execute the test function. "
+        "If only specific exception(s) are expected, you can list them in "
+        "raises, and if the test fails in other ways, it will be reported as "
+        "a true failure. See http://pytest.org/latest/skipping.html",
+    )
+
+
+@hookimpl(tryfirst=True)
+def pytest_runtest_setup(item):
+    # Check if skip or skipif are specified as pytest marks
+    item._skipped_by_mark = False
+    eval_skipif = MarkEvaluator(item, "skipif")
+    if eval_skipif.istrue():
+        item._skipped_by_mark = True
+        skip(eval_skipif.getexplanation())
+
+    for skip_info in item.iter_markers(name="skip"):
+        item._skipped_by_mark = True
+        if "reason" in skip_info.kwargs:
+            skip(skip_info.kwargs["reason"])
+        elif skip_info.args:
+            skip(skip_info.args[0])
+        else:
+            skip("unconditional skip")
+
+    item._evalxfail = MarkEvaluator(item, "xfail")
+    check_xfail_no_run(item)
+
+
+@hookimpl(hookwrapper=True)
+def pytest_pyfunc_call(pyfuncitem):
+    check_xfail_no_run(pyfuncitem)
+    outcome = yield
+    passed = outcome.excinfo is None
+    if passed:
+        check_strict_xfail(pyfuncitem)
+
+
+def check_xfail_no_run(item):
+    """check xfail(run=False)"""
+    if not item.config.option.runxfail:
+        evalxfail = item._evalxfail
+        if evalxfail.istrue():
+            if not evalxfail.get("run", True):
+                xfail("[NOTRUN] " + evalxfail.getexplanation())
+
+
+def check_strict_xfail(pyfuncitem):
+    """check xfail(strict=True) for the given PASSING test"""
+    evalxfail = pyfuncitem._evalxfail
+    if evalxfail.istrue():
+        strict_default = pyfuncitem.config.getini("xfail_strict")
+        is_strict_xfail = evalxfail.get("strict", strict_default)
+        if is_strict_xfail:
+            del pyfuncitem._evalxfail
+            explanation = evalxfail.getexplanation()
+            fail("[XPASS(strict)] " + explanation, pytrace=False)
+
+
+@hookimpl(hookwrapper=True)
+def pytest_runtest_makereport(item, call):
+    outcome = yield
+    rep = outcome.get_result()
+    evalxfail = getattr(item, "_evalxfail", None)
+    # unitttest special case, see setting of _unexpectedsuccess
+    if hasattr(item, "_unexpectedsuccess") and rep.when == "call":
+        from _pytest.compat import _is_unittest_unexpected_success_a_failure
+
+        if item._unexpectedsuccess:
+            rep.longrepr = "Unexpected success: {}".format(item._unexpectedsuccess)
+        else:
+            rep.longrepr = "Unexpected success"
+        if _is_unittest_unexpected_success_a_failure():
+            rep.outcome = "failed"
+        else:
+            rep.outcome = "passed"
+            rep.wasxfail = rep.longrepr
+    elif item.config.option.runxfail:
+        pass  # don't interefere
+    elif call.excinfo and call.excinfo.errisinstance(xfail.Exception):
+        rep.wasxfail = "reason: " + call.excinfo.value.msg
+        rep.outcome = "skipped"
+    elif evalxfail and not rep.skipped and evalxfail.wasvalid() and evalxfail.istrue():
+        if call.excinfo:
+            if evalxfail.invalidraise(call.excinfo.value):
+                rep.outcome = "failed"
+            else:
+                rep.outcome = "skipped"
+                rep.wasxfail = evalxfail.getexplanation()
+        elif call.when == "call":
+            strict_default = item.config.getini("xfail_strict")
+            is_strict_xfail = evalxfail.get("strict", strict_default)
+            explanation = evalxfail.getexplanation()
+            if is_strict_xfail:
+                rep.outcome = "failed"
+                rep.longrepr = "[XPASS(strict)] {}".format(explanation)
+            else:
+                rep.outcome = "passed"
+                rep.wasxfail = explanation
+    elif (
+        getattr(item, "_skipped_by_mark", False)
+        and rep.skipped
+        and type(rep.longrepr) is tuple
+    ):
+        # skipped by mark.skipif; change the location of the failure
+        # to point to the item definition, otherwise it will display
+        # the location of where the skip exception was raised within pytest
+        filename, line, reason = rep.longrepr
+        filename, line = item.location[:2]
+        rep.longrepr = filename, line, reason
+
+
+# called by terminalreporter progress reporting
+
+
+def pytest_report_teststatus(report):
+    if hasattr(report, "wasxfail"):
+        if report.skipped:
+            return "xfailed", "x", "xfail"
+        elif report.passed:
+            return "xpassed", "X", ("XPASS", {"yellow": True})
+
+
+# called by the terminalreporter instance/plugin
+
+
+def pytest_terminal_summary(terminalreporter):
+    tr = terminalreporter
+    if not tr.reportchars:
+        # for name in "xfailed skipped failed xpassed":
+        #    if not tr.stats.get(name, 0):
+        #        tr.write_line("HINT: use '-r' option to see extra "
+        #              "summary info about tests")
+        #        break
+        return
+
+    lines = []
+    for char in tr.reportchars:
+        action = REPORTCHAR_ACTIONS.get(char, lambda tr, lines: None)
+        action(terminalreporter, lines)
+
+    if lines:
+        tr._tw.sep("=", "short test summary info")
+        for line in lines:
+            tr._tw.line(line)
+
+
+def show_simple(terminalreporter, lines, stat, format):
+    failed = terminalreporter.stats.get(stat)
+    if failed:
+        for rep in failed:
+            pos = terminalreporter.config.cwd_relative_nodeid(rep.nodeid)
+            lines.append(format % (pos,))
+
+
+def show_xfailed(terminalreporter, lines):
+    xfailed = terminalreporter.stats.get("xfailed")
+    if xfailed:
+        for rep in xfailed:
+            pos = terminalreporter.config.cwd_relative_nodeid(rep.nodeid)
+            reason = rep.wasxfail
+            lines.append("XFAIL %s" % (pos,))
+            if reason:
+                lines.append("  " + str(reason))
+
+
+def show_xpassed(terminalreporter, lines):
+    xpassed = terminalreporter.stats.get("xpassed")
+    if xpassed:
+        for rep in xpassed:
+            pos = terminalreporter.config.cwd_relative_nodeid(rep.nodeid)
+            reason = rep.wasxfail
+            lines.append("XPASS %s %s" % (pos, reason))
+
+
+def folded_skips(skipped):
+    d = {}
+    for event in skipped:
+        key = event.longrepr
+        assert len(key) == 3, (event, key)
+        keywords = getattr(event, "keywords", {})
+        # folding reports with global pytestmark variable
+        # this is workaround, because for now we cannot identify the scope of a skip marker
+        # TODO: revisit after marks scope would be fixed
+        when = getattr(event, "when", None)
+        if when == "setup" and "skip" in keywords and "pytestmark" not in keywords:
+            key = (key[0], None, key[2])
+        d.setdefault(key, []).append(event)
+    values = []
+    for key, events in d.items():
+        values.append((len(events),) + key)
+    return values
+
+
+def show_skipped(terminalreporter, lines):
+    tr = terminalreporter
+    skipped = tr.stats.get("skipped", [])
+    if skipped:
+        # if not tr.hasopt('skipped'):
+        #    tr.write_line(
+        #        "%d skipped tests, specify -rs for more info" %
+        #        len(skipped))
+        #    return
+        fskips = folded_skips(skipped)
+        if fskips:
+            # tr.write_sep("_", "skipped test summary")
+            for num, fspath, lineno, reason in fskips:
+                if reason.startswith("Skipped: "):
+                    reason = reason[9:]
+                if lineno is not None:
+                    lines.append(
+                        "SKIP [%d] %s:%d: %s" % (num, fspath, lineno + 1, reason)
+                    )
+                else:
+                    lines.append("SKIP [%d] %s: %s" % (num, fspath, reason))
+
+
+def shower(stat, format):
+    def show_(terminalreporter, lines):
+        return show_simple(terminalreporter, lines, stat, format)
+
+    return show_
+
+
+REPORTCHAR_ACTIONS = {
+    "x": show_xfailed,
+    "X": show_xpassed,
+    "f": shower("failed", "FAIL %s"),
+    "F": shower("failed", "FAIL %s"),
+    "s": show_skipped,
+    "S": show_skipped,
+    "p": shower("passed", "PASSED %s"),
+    "E": shower("error", "ERROR %s"),
+}

src/_pytest/terminal.py

@@ -0,0 +1,832 @@
+""" terminal reporting of the full testing process.
+
+This is a good source for looking at the various reporting hooks.
+"""
+from __future__ import absolute_import, division, print_function
+
+import itertools
+import platform
+import sys
+import time
+
+import pluggy
+import py
+import six
+from more_itertools import collapse
+
+import pytest
+from _pytest import nodes
+from _pytest.main import (
+    EXIT_OK,
+    EXIT_TESTSFAILED,
+    EXIT_INTERRUPTED,
+    EXIT_USAGEERROR,
+    EXIT_NOTESTSCOLLECTED,
+)
+
+
+import argparse
+
+
+class MoreQuietAction(argparse.Action):
+    """
+    a modified copy of the argparse count action which counts down and updates
+    the legacy quiet attribute at the same time
+
+    used to unify verbosity handling
+    """
+
+    def __init__(self, option_strings, dest, default=None, required=False, help=None):
+        super(MoreQuietAction, self).__init__(
+            option_strings=option_strings,
+            dest=dest,
+            nargs=0,
+            default=default,
+            required=required,
+            help=help,
+        )
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        new_count = getattr(namespace, self.dest, 0) - 1
+        setattr(namespace, self.dest, new_count)
+        # todo Deprecate config.quiet
+        namespace.quiet = getattr(namespace, "quiet", 0) + 1
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("terminal reporting", "reporting", after="general")
+    group._addoption(
+        "-v",
+        "--verbose",
+        action="count",
+        default=0,
+        dest="verbose",
+        help="increase verbosity.",
+    ),
+    group._addoption(
+        "-q",
+        "--quiet",
+        action=MoreQuietAction,
+        default=0,
+        dest="verbose",
+        help="decrease verbosity.",
+    ),
+    group._addoption(
+        "--verbosity", dest="verbose", type=int, default=0, help="set verbosity"
+    )
+    group._addoption(
+        "-r",
+        action="store",
+        dest="reportchars",
+        default="",
+        metavar="chars",
+        help="show extra test summary info as specified by chars (f)ailed, "
+        "(E)error, (s)skipped, (x)failed, (X)passed, "
+        "(p)passed, (P)passed with output, (a)all except pP. "
+        "Warnings are displayed at all times except when "
+        "--disable-warnings is set",
+    )
+    group._addoption(
+        "--disable-warnings",
+        "--disable-pytest-warnings",
+        default=False,
+        dest="disable_warnings",
+        action="store_true",
+        help="disable warnings summary",
+    )
+    group._addoption(
+        "-l",
+        "--showlocals",
+        action="store_true",
+        dest="showlocals",
+        default=False,
+        help="show locals in tracebacks (disabled by default).",
+    )
+    group._addoption(
+        "--tb",
+        metavar="style",
+        action="store",
+        dest="tbstyle",
+        default="auto",
+        choices=["auto", "long", "short", "no", "line", "native"],
+        help="traceback print mode (auto/long/short/line/native/no).",
+    )
+    group._addoption(
+        "--show-capture",
+        action="store",
+        dest="showcapture",
+        choices=["no", "stdout", "stderr", "log", "all"],
+        default="all",
+        help="Controls how captured stdout/stderr/log is shown on failed tests. "
+        "Default is 'all'.",
+    )
+    group._addoption(
+        "--fulltrace",
+        "--full-trace",
+        action="store_true",
+        default=False,
+        help="don't cut any tracebacks (default is to cut).",
+    )
+    group._addoption(
+        "--color",
+        metavar="color",
+        action="store",
+        dest="color",
+        default="auto",
+        choices=["yes", "no", "auto"],
+        help="color terminal output (yes/no/auto).",
+    )
+
+    parser.addini(
+        "console_output_style",
+        help="console output: classic or with additional progress information (classic|progress).",
+        default="progress",
+    )
+
+
+def pytest_configure(config):
+    reporter = TerminalReporter(config, sys.stdout)
+    config.pluginmanager.register(reporter, "terminalreporter")
+    if config.option.debug or config.option.traceconfig:
+
+        def mywriter(tags, args):
+            msg = " ".join(map(str, args))
+            reporter.write_line("[traceconfig] " + msg)
+
+        config.trace.root.setprocessor("pytest:config", mywriter)
+
+
+def getreportopt(config):
+    reportopts = ""
+    reportchars = config.option.reportchars
+    if not config.option.disable_warnings and "w" not in reportchars:
+        reportchars += "w"
+    elif config.option.disable_warnings and "w" in reportchars:
+        reportchars = reportchars.replace("w", "")
+    if reportchars:
+        for char in reportchars:
+            if char not in reportopts and char != "a":
+                reportopts += char
+            elif char == "a":
+                reportopts = "fEsxXw"
+    return reportopts
+
+
+def pytest_report_teststatus(report):
+    if report.passed:
+        letter = "."
+    elif report.skipped:
+        letter = "s"
+    elif report.failed:
+        letter = "F"
+        if report.when != "call":
+            letter = "f"
+    return report.outcome, letter, report.outcome.upper()
+
+
+class WarningReport(object):
+    """
+    Simple structure to hold warnings information captured by ``pytest_logwarning``.
+    """
+
+    def __init__(self, code, message, nodeid=None, fslocation=None):
+        """
+        :param code: unused
+        :param str message: user friendly message about the warning
+        :param str|None nodeid: node id that generated the warning (see ``get_location``).
+        :param tuple|py.path.local fslocation:
+            file system location of the source of the warning (see ``get_location``).
+        """
+        self.code = code
+        self.message = message
+        self.nodeid = nodeid
+        self.fslocation = fslocation
+
+    def get_location(self, config):
+        """
+        Returns the more user-friendly information about the location
+        of a warning, or None.
+        """
+        if self.nodeid:
+            return self.nodeid
+        if self.fslocation:
+            if isinstance(self.fslocation, tuple) and len(self.fslocation) >= 2:
+                filename, linenum = self.fslocation[:2]
+                relpath = py.path.local(filename).relto(config.invocation_dir)
+                return "%s:%s" % (relpath, linenum)
+            else:
+                return str(self.fslocation)
+        return None
+
+
+class TerminalReporter(object):
+    def __init__(self, config, file=None):
+        import _pytest.config
+
+        self.config = config
+        self.verbosity = self.config.option.verbose
+        self.showheader = self.verbosity >= 0
+        self.showfspath = self.verbosity >= 0
+        self.showlongtestinfo = self.verbosity > 0
+        self._numcollected = 0
+        self._session = None
+
+        self.stats = {}
+        self.startdir = py.path.local()
+        if file is None:
+            file = sys.stdout
+        self._tw = _pytest.config.create_terminal_writer(config, file)
+        # self.writer will be deprecated in pytest-3.4
+        self.writer = self._tw
+        self._screen_width = self._tw.fullwidth
+        self.currentfspath = None
+        self.reportchars = getreportopt(config)
+        self.hasmarkup = self._tw.hasmarkup
+        self.isatty = file.isatty()
+        self._progress_nodeids_reported = set()
+        self._show_progress_info = self._determine_show_progress_info()
+
+    def _determine_show_progress_info(self):
+        """Return True if we should display progress information based on the current config"""
+        # do not show progress if we are not capturing output (#3038)
+        if self.config.getoption("capture") == "no":
+            return False
+        # do not show progress if we are showing fixture setup/teardown
+        if self.config.getoption("setupshow"):
+            return False
+        return self.config.getini("console_output_style") == "progress"
+
+    def hasopt(self, char):
+        char = {"xfailed": "x", "skipped": "s"}.get(char, char)
+        return char in self.reportchars
+
+    def write_fspath_result(self, nodeid, res):
+        fspath = self.config.rootdir.join(nodeid.split("::")[0])
+        if fspath != self.currentfspath:
+            if self.currentfspath is not None:
+                self._write_progress_information_filling_space()
+            self.currentfspath = fspath
+            fspath = self.startdir.bestrelpath(fspath)
+            self._tw.line()
+            self._tw.write(fspath + " ")
+        self._tw.write(res)
+
+    def write_ensure_prefix(self, prefix, extra="", **kwargs):
+        if self.currentfspath != prefix:
+            self._tw.line()
+            self.currentfspath = prefix
+            self._tw.write(prefix)
+        if extra:
+            self._tw.write(extra, **kwargs)
+            self.currentfspath = -2
+
+    def ensure_newline(self):
+        if self.currentfspath:
+            self._tw.line()
+            self.currentfspath = None
+
+    def write(self, content, **markup):
+        self._tw.write(content, **markup)
+
+    def write_line(self, line, **markup):
+        if not isinstance(line, six.text_type):
+            line = six.text_type(line, errors="replace")
+        self.ensure_newline()
+        self._tw.line(line, **markup)
+
+    def rewrite(self, line, **markup):
+        """
+        Rewinds the terminal cursor to the beginning and writes the given line.
+
+        :kwarg erase: if True, will also add spaces until the full terminal width to ensure
+            previous lines are properly erased.
+
+        The rest of the keyword arguments are markup instructions.
+        """
+        erase = markup.pop("erase", False)
+        if erase:
+            fill_count = self._tw.fullwidth - len(line) - 1
+            fill = " " * fill_count
+        else:
+            fill = ""
+        line = str(line)
+        self._tw.write("\r" + line + fill, **markup)
+
+    def write_sep(self, sep, title=None, **markup):
+        self.ensure_newline()
+        self._tw.sep(sep, title, **markup)
+
+    def section(self, title, sep="=", **kw):
+        self._tw.sep(sep, title, **kw)
+
+    def line(self, msg, **kw):
+        self._tw.line(msg, **kw)
+
+    def pytest_internalerror(self, excrepr):
+        for line in six.text_type(excrepr).split("\n"):
+            self.write_line("INTERNALERROR> " + line)
+        return 1
+
+    def pytest_logwarning(self, code, fslocation, message, nodeid):
+        warnings = self.stats.setdefault("warnings", [])
+        warning = WarningReport(
+            code=code, fslocation=fslocation, message=message, nodeid=nodeid
+        )
+        warnings.append(warning)
+
+    def pytest_plugin_registered(self, plugin):
+        if self.config.option.traceconfig:
+            msg = "PLUGIN registered: %s" % (plugin,)
+            # XXX this event may happen during setup/teardown time
+            #     which unfortunately captures our output here
+            #     which garbles our output if we use self.write_line
+            self.write_line(msg)
+
+    def pytest_deselected(self, items):
+        self.stats.setdefault("deselected", []).extend(items)
+
+    def pytest_runtest_logstart(self, nodeid, location):
+        # ensure that the path is printed before the
+        # 1st test of a module starts running
+        if self.showlongtestinfo:
+            line = self._locationline(nodeid, *location)
+            self.write_ensure_prefix(line, "")
+        elif self.showfspath:
+            fsid = nodeid.split("::")[0]
+            self.write_fspath_result(fsid, "")
+
+    def pytest_runtest_logreport(self, report):
+        rep = report
+        res = self.config.hook.pytest_report_teststatus(report=rep)
+        cat, letter, word = res
+        if isinstance(word, tuple):
+            word, markup = word
+        else:
+            markup = None
+        self.stats.setdefault(cat, []).append(rep)
+        self._tests_ran = True
+        if not letter and not word:
+            # probably passed setup/teardown
+            return
+        running_xdist = hasattr(rep, "node")
+        if self.verbosity <= 0:
+            if not running_xdist and self.showfspath:
+                self.write_fspath_result(rep.nodeid, letter)
+            else:
+                self._tw.write(letter)
+        else:
+            self._progress_nodeids_reported.add(rep.nodeid)
+            if markup is None:
+                if rep.passed:
+                    markup = {"green": True}
+                elif rep.failed:
+                    markup = {"red": True}
+                elif rep.skipped:
+                    markup = {"yellow": True}
+                else:
+                    markup = {}
+            line = self._locationline(rep.nodeid, *rep.location)
+            if not running_xdist:
+                self.write_ensure_prefix(line, word, **markup)
+                if self._show_progress_info:
+                    self._write_progress_information_filling_space()
+            else:
+                self.ensure_newline()
+                self._tw.write("[%s]" % rep.node.gateway.id)
+                if self._show_progress_info:
+                    self._tw.write(
+                        self._get_progress_information_message() + " ", cyan=True
+                    )
+                else:
+                    self._tw.write(" ")
+                self._tw.write(word, **markup)
+                self._tw.write(" " + line)
+                self.currentfspath = -2
+
+    def pytest_runtest_logfinish(self, nodeid):
+        if self.verbosity <= 0 and self._show_progress_info:
+            self._progress_nodeids_reported.add(nodeid)
+            last_item = (
+                len(self._progress_nodeids_reported) == self._session.testscollected
+            )
+            if last_item:
+                self._write_progress_information_filling_space()
+            else:
+                past_edge = (
+                    self._tw.chars_on_current_line + self._PROGRESS_LENGTH + 1
+                    >= self._screen_width
+                )
+                if past_edge:
+                    msg = self._get_progress_information_message()
+                    self._tw.write(msg + "\n", cyan=True)
+
+    _PROGRESS_LENGTH = len(" [100%]")
+
+    def _get_progress_information_message(self):
+        if self.config.getoption("capture") == "no":
+            return ""
+        collected = self._session.testscollected
+        if collected:
+            progress = len(self._progress_nodeids_reported) * 100 // collected
+            return " [{:3d}%]".format(progress)
+        return " [100%]"
+
+    def _write_progress_information_filling_space(self):
+        msg = self._get_progress_information_message()
+        fill = " " * (
+            self._tw.fullwidth - self._tw.chars_on_current_line - len(msg) - 1
+        )
+        self.write(fill + msg, cyan=True)
+
+    def pytest_collection(self):
+        if not self.isatty and self.config.option.verbose >= 1:
+            self.write("collecting ... ", bold=True)
+
+    def pytest_collectreport(self, report):
+        if report.failed:
+            self.stats.setdefault("error", []).append(report)
+        elif report.skipped:
+            self.stats.setdefault("skipped", []).append(report)
+        items = [x for x in report.result if isinstance(x, pytest.Item)]
+        self._numcollected += len(items)
+        if self.isatty:
+            # self.write_fspath_result(report.nodeid, 'E')
+            self.report_collect()
+
+    def report_collect(self, final=False):
+        if self.config.option.verbose < 0:
+            return
+
+        errors = len(self.stats.get("error", []))
+        skipped = len(self.stats.get("skipped", []))
+        deselected = len(self.stats.get("deselected", []))
+        if final:
+            line = "collected "
+        else:
+            line = "collecting "
+        line += (
+            str(self._numcollected) + " item" + ("" if self._numcollected == 1 else "s")
+        )
+        if errors:
+            line += " / %d errors" % errors
+        if deselected:
+            line += " / %d deselected" % deselected
+        if skipped:
+            line += " / %d skipped" % skipped
+        if self.isatty:
+            self.rewrite(line, bold=True, erase=True)
+            if final:
+                self.write("\n")
+        else:
+            self.write_line(line)
+
+    @pytest.hookimpl(trylast=True)
+    def pytest_collection_modifyitems(self):
+        self.report_collect(True)
+
+    @pytest.hookimpl(trylast=True)
+    def pytest_sessionstart(self, session):
+        self._session = session
+        self._sessionstarttime = time.time()
+        if not self.showheader:
+            return
+        self.write_sep("=", "test session starts", bold=True)
+        verinfo = platform.python_version()
+        msg = "platform %s -- Python %s" % (sys.platform, verinfo)
+        if hasattr(sys, "pypy_version_info"):
+            verinfo = ".".join(map(str, sys.pypy_version_info[:3]))
+            msg += "[pypy-%s-%s]" % (verinfo, sys.pypy_version_info[3])
+        msg += ", pytest-%s, py-%s, pluggy-%s" % (
+            pytest.__version__,
+            py.__version__,
+            pluggy.__version__,
+        )
+        if (
+            self.verbosity > 0
+            or self.config.option.debug
+            or getattr(self.config.option, "pastebin", None)
+        ):
+            msg += " -- " + str(sys.executable)
+        self.write_line(msg)
+        lines = self.config.hook.pytest_report_header(
+            config=self.config, startdir=self.startdir
+        )
+        self._write_report_lines_from_hooks(lines)
+
+    def _write_report_lines_from_hooks(self, lines):
+        lines.reverse()
+        for line in collapse(lines):
+            self.write_line(line)
+
+    def pytest_report_header(self, config):
+        inifile = ""
+        if config.inifile:
+            inifile = " " + config.rootdir.bestrelpath(config.inifile)
+        lines = ["rootdir: %s, inifile:%s" % (config.rootdir, inifile)]
+
+        plugininfo = config.pluginmanager.list_plugin_distinfo()
+        if plugininfo:
+
+            lines.append("plugins: %s" % ", ".join(_plugin_nameversions(plugininfo)))
+        return lines
+
+    def pytest_collection_finish(self, session):
+        if self.config.option.collectonly:
+            self._printcollecteditems(session.items)
+            if self.stats.get("failed"):
+                self._tw.sep("!", "collection failures")
+                for rep in self.stats.get("failed"):
+                    rep.toterminal(self._tw)
+                return 1
+            return 0
+        lines = self.config.hook.pytest_report_collectionfinish(
+            config=self.config, startdir=self.startdir, items=session.items
+        )
+        self._write_report_lines_from_hooks(lines)
+
+    def _printcollecteditems(self, items):
+        # to print out items and their parent collectors
+        # we take care to leave out Instances aka ()
+        # because later versions are going to get rid of them anyway
+        if self.config.option.verbose < 0:
+            if self.config.option.verbose < -1:
+                counts = {}
+                for item in items:
+                    name = item.nodeid.split("::", 1)[0]
+                    counts[name] = counts.get(name, 0) + 1
+                for name, count in sorted(counts.items()):
+                    self._tw.line("%s: %d" % (name, count))
+            else:
+                for item in items:
+                    nodeid = item.nodeid
+                    nodeid = nodeid.replace("::()::", "::")
+                    self._tw.line(nodeid)
+            return
+        stack = []
+        indent = ""
+        for item in items:
+            needed_collectors = item.listchain()[1:]  # strip root node
+            while stack:
+                if stack == needed_collectors[: len(stack)]:
+                    break
+                stack.pop()
+            for col in needed_collectors[len(stack) :]:
+                stack.append(col)
+                # if col.name == "()":
+                #    continue
+                indent = (len(stack) - 1) * "  "
+                self._tw.line("%s%s" % (indent, col))
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_sessionfinish(self, exitstatus):
+        outcome = yield
+        outcome.get_result()
+        self._tw.line("")
+        summary_exit_codes = (
+            EXIT_OK,
+            EXIT_TESTSFAILED,
+            EXIT_INTERRUPTED,
+            EXIT_USAGEERROR,
+            EXIT_NOTESTSCOLLECTED,
+        )
+        if exitstatus in summary_exit_codes:
+            self.config.hook.pytest_terminal_summary(
+                terminalreporter=self, exitstatus=exitstatus
+            )
+        if exitstatus == EXIT_INTERRUPTED:
+            self._report_keyboardinterrupt()
+            del self._keyboardinterrupt_memo
+        self.summary_stats()
+
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_terminal_summary(self):
+        self.summary_errors()
+        self.summary_failures()
+        yield
+        self.summary_warnings()
+        self.summary_passes()
+
+    def pytest_keyboard_interrupt(self, excinfo):
+        self._keyboardinterrupt_memo = excinfo.getrepr(funcargs=True)
+
+    def pytest_unconfigure(self):
+        if hasattr(self, "_keyboardinterrupt_memo"):
+            self._report_keyboardinterrupt()
+
+    def _report_keyboardinterrupt(self):
+        excrepr = self._keyboardinterrupt_memo
+        msg = excrepr.reprcrash.message
+        self.write_sep("!", msg)
+        if "KeyboardInterrupt" in msg:
+            if self.config.option.fulltrace:
+                excrepr.toterminal(self._tw)
+            else:
+                excrepr.reprcrash.toterminal(self._tw)
+                self._tw.line(
+                    "(to show a full traceback on KeyboardInterrupt use --fulltrace)",
+                    yellow=True,
+                )
+
+    def _locationline(self, nodeid, fspath, lineno, domain):
+        def mkrel(nodeid):
+            line = self.config.cwd_relative_nodeid(nodeid)
+            if domain and line.endswith(domain):
+                line = line[: -len(domain)]
+                values = domain.split("[")
+                values[0] = values[0].replace(".", "::")  # don't replace '.' in params
+                line += "[".join(values)
+            return line
+
+        # collect_fspath comes from testid which has a "/"-normalized path
+
+        if fspath:
+            res = mkrel(nodeid).replace("::()", "")  # parens-normalization
+            if nodeid.split("::")[0] != fspath.replace("\\", nodes.SEP):
+                res += " <- " + self.startdir.bestrelpath(fspath)
+        else:
+            res = "[location]"
+        return res + " "
+
+    def _getfailureheadline(self, rep):
+        if hasattr(rep, "location"):
+            fspath, lineno, domain = rep.location
+            return domain
+        else:
+            return "test session"  # XXX?
+
+    def _getcrashline(self, rep):
+        try:
+            return str(rep.longrepr.reprcrash)
+        except AttributeError:
+            try:
+                return str(rep.longrepr)[:50]
+            except AttributeError:
+                return ""
+
+    #
+    # summaries for sessionfinish
+    #
+    def getreports(self, name):
+        values = []
+        for x in self.stats.get(name, []):
+            if not hasattr(x, "_pdbshown"):
+                values.append(x)
+        return values
+
+    def summary_warnings(self):
+        if self.hasopt("w"):
+            all_warnings = self.stats.get("warnings")
+            if not all_warnings:
+                return
+
+            grouped = itertools.groupby(
+                all_warnings, key=lambda wr: wr.get_location(self.config)
+            )
+
+            self.write_sep("=", "warnings summary", yellow=True, bold=False)
+            for location, warning_records in grouped:
+                self._tw.line(str(location) if location else "<undetermined location>")
+                for w in warning_records:
+                    lines = w.message.splitlines()
+                    indented = "\n".join("  " + x for x in lines)
+                    self._tw.line(indented)
+                self._tw.line()
+            self._tw.line("-- Docs: http://doc.pytest.org/en/latest/warnings.html")
+
+    def summary_passes(self):
+        if self.config.option.tbstyle != "no":
+            if self.hasopt("P"):
+                reports = self.getreports("passed")
+                if not reports:
+                    return
+                self.write_sep("=", "PASSES")
+                for rep in reports:
+                    msg = self._getfailureheadline(rep)
+                    self.write_sep("_", msg)
+                    self._outrep_summary(rep)
+
+    def print_teardown_sections(self, rep):
+        for secname, content in rep.sections:
+            if "teardown" in secname:
+                self._tw.sep("-", secname)
+                if content[-1:] == "\n":
+                    content = content[:-1]
+                self._tw.line(content)
+
+    def summary_failures(self):
+        if self.config.option.tbstyle != "no":
+            reports = self.getreports("failed")
+            if not reports:
+                return
+            self.write_sep("=", "FAILURES")
+            for rep in reports:
+                if self.config.option.tbstyle == "line":
+                    line = self._getcrashline(rep)
+                    self.write_line(line)
+                else:
+                    msg = self._getfailureheadline(rep)
+                    markup = {"red": True, "bold": True}
+                    self.write_sep("_", msg, **markup)
+                    self._outrep_summary(rep)
+                    for report in self.getreports(""):
+                        if report.nodeid == rep.nodeid and report.when == "teardown":
+                            self.print_teardown_sections(report)
+
+    def summary_errors(self):
+        if self.config.option.tbstyle != "no":
+            reports = self.getreports("error")
+            if not reports:
+                return
+            self.write_sep("=", "ERRORS")
+            for rep in self.stats["error"]:
+                msg = self._getfailureheadline(rep)
+                if not hasattr(rep, "when"):
+                    # collect
+                    msg = "ERROR collecting " + msg
+                elif rep.when == "setup":
+                    msg = "ERROR at setup of " + msg
+                elif rep.when == "teardown":
+                    msg = "ERROR at teardown of " + msg
+                self.write_sep("_", msg)
+                self._outrep_summary(rep)
+
+    def _outrep_summary(self, rep):
+        rep.toterminal(self._tw)
+        showcapture = self.config.option.showcapture
+        if showcapture == "no":
+            return
+        for secname, content in rep.sections:
+            if showcapture != "all" and showcapture not in secname:
+                continue
+            self._tw.sep("-", secname)
+            if content[-1:] == "\n":
+                content = content[:-1]
+            self._tw.line(content)
+
+    def summary_stats(self):
+        session_duration = time.time() - self._sessionstarttime
+        (line, color) = build_summary_stats_line(self.stats)
+        msg = "%s in %.2f seconds" % (line, session_duration)
+        markup = {color: True, "bold": True}
+
+        if self.verbosity >= 0:
+            self.write_sep("=", msg, **markup)
+        if self.verbosity == -1:
+            self.write_line(msg, **markup)
+
+
+def repr_pythonversion(v=None):
+    if v is None:
+        v = sys.version_info
+    try:
+        return "%s.%s.%s-%s-%s" % v
+    except (TypeError, ValueError):
+        return str(v)
+
+
+def build_summary_stats_line(stats):
+    keys = (
+        "failed passed skipped deselected " "xfailed xpassed warnings error"
+    ).split()
+    unknown_key_seen = False
+    for key in stats.keys():
+        if key not in keys:
+            if key:  # setup/teardown reports have an empty key, ignore them
+                keys.append(key)
+                unknown_key_seen = True
+    parts = []
+    for key in keys:
+        val = stats.get(key, None)
+        if val:
+            parts.append("%d %s" % (len(val), key))
+
+    if parts:
+        line = ", ".join(parts)
+    else:
+        line = "no tests ran"
+
+    if "failed" in stats or "error" in stats:
+        color = "red"
+    elif "warnings" in stats or unknown_key_seen:
+        color = "yellow"
+    elif "passed" in stats:
+        color = "green"
+    else:
+        color = "yellow"
+
+    return (line, color)
+
+
+def _plugin_nameversions(plugininfo):
+    values = []
+    for plugin, dist in plugininfo:
+        # gets us name and version!
+        name = "{dist.project_name}-{dist.version}".format(dist=dist)
+        # questionable convenience, but it keeps things short
+        if name.startswith("pytest-"):
+            name = name[7:]
+        # we decided to print python package names
+        # they can have more than one plugin
+        if name not in values:
+            values.append(name)
+    return values

src/_pytest/tmpdir.py

@@ -0,0 +1,131 @@
+""" support for providing temporary directories to test functions.  """
+from __future__ import absolute_import, division, print_function
+
+import re
+
+import pytest
+import py
+from _pytest.monkeypatch import MonkeyPatch
+
+
+class TempdirFactory(object):
+    """Factory for temporary directories under the common base temp directory.
+
+    The base directory can be configured using the ``--basetemp`` option.
+    """
+
+    def __init__(self, config):
+        self.config = config
+        self.trace = config.trace.get("tmpdir")
+
+    def ensuretemp(self, string, dir=1):
+        """ (deprecated) return temporary directory path with
+            the given string as the trailing part.  It is usually
+            better to use the 'tmpdir' function argument which
+            provides an empty unique-per-test-invocation directory
+            and is guaranteed to be empty.
+        """
+        # py.log._apiwarn(">1.1", "use tmpdir function argument")
+        return self.getbasetemp().ensure(string, dir=dir)
+
+    def mktemp(self, basename, numbered=True):
+        """Create a subdirectory of the base temporary directory and return it.
+        If ``numbered``, ensure the directory is unique by adding a number
+        prefix greater than any existing one.
+        """
+        basetemp = self.getbasetemp()
+        if not numbered:
+            p = basetemp.mkdir(basename)
+        else:
+            p = py.path.local.make_numbered_dir(
+                prefix=basename, keep=0, rootdir=basetemp, lock_timeout=None
+            )
+        self.trace("mktemp", p)
+        return p
+
+    def getbasetemp(self):
+        """ return base temporary directory. """
+        try:
+            return self._basetemp
+        except AttributeError:
+            basetemp = self.config.option.basetemp
+            if basetemp:
+                basetemp = py.path.local(basetemp)
+                if basetemp.check():
+                    basetemp.remove()
+                basetemp.mkdir()
+            else:
+                temproot = py.path.local.get_temproot()
+                user = get_user()
+                if user:
+                    # use a sub-directory in the temproot to speed-up
+                    # make_numbered_dir() call
+                    rootdir = temproot.join("pytest-of-%s" % user)
+                else:
+                    rootdir = temproot
+                rootdir.ensure(dir=1)
+                basetemp = py.path.local.make_numbered_dir(
+                    prefix="pytest-", rootdir=rootdir
+                )
+            self._basetemp = t = basetemp.realpath()
+            self.trace("new basetemp", t)
+            return t
+
+    def finish(self):
+        self.trace("finish")
+
+
+def get_user():
+    """Return the current user name, or None if getuser() does not work
+    in the current environment (see #1010).
+    """
+    import getpass
+
+    try:
+        return getpass.getuser()
+    except (ImportError, KeyError):
+        return None
+
+
+# backward compatibility
+TempdirHandler = TempdirFactory
+
+
+def pytest_configure(config):
+    """Create a TempdirFactory and attach it to the config object.
+
+    This is to comply with existing plugins which expect the handler to be
+    available at pytest_configure time, but ideally should be moved entirely
+    to the tmpdir_factory session fixture.
+    """
+    mp = MonkeyPatch()
+    t = TempdirFactory(config)
+    config._cleanup.extend([mp.undo, t.finish])
+    mp.setattr(config, "_tmpdirhandler", t, raising=False)
+    mp.setattr(pytest, "ensuretemp", t.ensuretemp, raising=False)
+
+
+@pytest.fixture(scope="session")
+def tmpdir_factory(request):
+    """Return a TempdirFactory instance for the test session.
+    """
+    return request.config._tmpdirhandler
+
+
+@pytest.fixture
+def tmpdir(request, tmpdir_factory):
+    """Return a temporary directory path object
+    which is unique to each test function invocation,
+    created as a sub directory of the base temporary
+    directory.  The returned object is a `py.path.local`_
+    path object.
+
+    .. _`py.path.local`: https://py.readthedocs.io/en/latest/path.html
+    """
+    name = request.node.name
+    name = re.sub(r"[\W]", "_", name)
+    MAXVAL = 30
+    if len(name) > MAXVAL:
+        name = name[:MAXVAL]
+    x = tmpdir_factory.mktemp(name, numbered=True)
+    return x

src/_pytest/unittest.py

@@ -0,0 +1,251 @@
+""" discovery and running of std-library "unittest" style tests. """
+from __future__ import absolute_import, division, print_function
+
+import sys
+import traceback
+
+# for transferring markers
+import _pytest._code
+from _pytest.config import hookimpl
+from _pytest.outcomes import fail, skip, xfail
+from _pytest.python import transfer_markers, Class, Module, Function
+
+
+def pytest_pycollect_makeitem(collector, name, obj):
+    # has unittest been imported and is obj a subclass of its TestCase?
+    try:
+        if not issubclass(obj, sys.modules["unittest"].TestCase):
+            return
+    except Exception:
+        return
+    # yes, so let's collect it
+    return UnitTestCase(name, parent=collector)
+
+
+class UnitTestCase(Class):
+    # marker for fixturemanger.getfixtureinfo()
+    # to declare that our children do not support funcargs
+    nofuncargs = True
+
+    def setup(self):
+        cls = self.obj
+        if getattr(cls, "__unittest_skip__", False):
+            return  # skipped
+        setup = getattr(cls, "setUpClass", None)
+        if setup is not None:
+            setup()
+        teardown = getattr(cls, "tearDownClass", None)
+        if teardown is not None:
+            self.addfinalizer(teardown)
+        super(UnitTestCase, self).setup()
+
+    def collect(self):
+        from unittest import TestLoader
+
+        cls = self.obj
+        if not getattr(cls, "__test__", True):
+            return
+        self.session._fixturemanager.parsefactories(self, unittest=True)
+        loader = TestLoader()
+        module = self.getparent(Module).obj
+        foundsomething = False
+        for name in loader.getTestCaseNames(self.obj):
+            x = getattr(self.obj, name)
+            if not getattr(x, "__test__", True):
+                continue
+            funcobj = getattr(x, "im_func", x)
+            transfer_markers(funcobj, cls, module)
+            yield TestCaseFunction(name, parent=self, callobj=funcobj)
+            foundsomething = True
+
+        if not foundsomething:
+            runtest = getattr(self.obj, "runTest", None)
+            if runtest is not None:
+                ut = sys.modules.get("twisted.trial.unittest", None)
+                if ut is None or runtest != ut.TestCase.runTest:
+                    yield TestCaseFunction("runTest", parent=self)
+
+
+class TestCaseFunction(Function):
+    nofuncargs = True
+    _excinfo = None
+
+    def setup(self):
+        self._testcase = self.parent.obj(self.name)
+        self._fix_unittest_skip_decorator()
+        self._obj = getattr(self._testcase, self.name)
+        if hasattr(self._testcase, "setup_method"):
+            self._testcase.setup_method(self._obj)
+        if hasattr(self, "_request"):
+            self._request._fillfixtures()
+
+    def _fix_unittest_skip_decorator(self):
+        """
+        The @unittest.skip decorator calls functools.wraps(self._testcase)
+        The call to functools.wraps() fails unless self._testcase
+        has a __name__ attribute. This is usually automatically supplied
+        if the test is a function or method, but we need to add manually
+        here.
+
+        See issue #1169
+        """
+        if sys.version_info[0] == 2:
+            setattr(self._testcase, "__name__", self.name)
+
+    def teardown(self):
+        if hasattr(self._testcase, "teardown_method"):
+            self._testcase.teardown_method(self._obj)
+        # Allow garbage collection on TestCase instance attributes.
+        self._testcase = None
+        self._obj = None
+
+    def startTest(self, testcase):
+        pass
+
+    def _addexcinfo(self, rawexcinfo):
+        # unwrap potential exception info (see twisted trial support below)
+        rawexcinfo = getattr(rawexcinfo, "_rawexcinfo", rawexcinfo)
+        try:
+            excinfo = _pytest._code.ExceptionInfo(rawexcinfo)
+        except TypeError:
+            try:
+                try:
+                    values = traceback.format_exception(*rawexcinfo)
+                    values.insert(
+                        0,
+                        "NOTE: Incompatible Exception Representation, "
+                        "displaying natively:\n\n",
+                    )
+                    fail("".join(values), pytrace=False)
+                except (fail.Exception, KeyboardInterrupt):
+                    raise
+                except:  # noqa
+                    fail(
+                        "ERROR: Unknown Incompatible Exception "
+                        "representation:\n%r" % (rawexcinfo,),
+                        pytrace=False,
+                    )
+            except KeyboardInterrupt:
+                raise
+            except fail.Exception:
+                excinfo = _pytest._code.ExceptionInfo()
+        self.__dict__.setdefault("_excinfo", []).append(excinfo)
+
+    def addError(self, testcase, rawexcinfo):
+        self._addexcinfo(rawexcinfo)
+
+    def addFailure(self, testcase, rawexcinfo):
+        self._addexcinfo(rawexcinfo)
+
+    def addSkip(self, testcase, reason):
+        try:
+            skip(reason)
+        except skip.Exception:
+            self._skipped_by_mark = True
+            self._addexcinfo(sys.exc_info())
+
+    def addExpectedFailure(self, testcase, rawexcinfo, reason=""):
+        try:
+            xfail(str(reason))
+        except xfail.Exception:
+            self._addexcinfo(sys.exc_info())
+
+    def addUnexpectedSuccess(self, testcase, reason=""):
+        self._unexpectedsuccess = reason
+
+    def addSuccess(self, testcase):
+        pass
+
+    def stopTest(self, testcase):
+        pass
+
+    def _handle_skip(self):
+        # implements the skipping machinery (see #2137)
+        # analog to pythons Lib/unittest/case.py:run
+        testMethod = getattr(self._testcase, self._testcase._testMethodName)
+        if getattr(self._testcase.__class__, "__unittest_skip__", False) or getattr(
+            testMethod, "__unittest_skip__", False
+        ):
+            # If the class or method was skipped.
+            skip_why = getattr(
+                self._testcase.__class__, "__unittest_skip_why__", ""
+            ) or getattr(testMethod, "__unittest_skip_why__", "")
+            try:  # PY3, unittest2 on PY2
+                self._testcase._addSkip(self, self._testcase, skip_why)
+            except TypeError:  # PY2
+                if sys.version_info[0] != 2:
+                    raise
+                self._testcase._addSkip(self, skip_why)
+            return True
+        return False
+
+    def runtest(self):
+        if self.config.pluginmanager.get_plugin("pdbinvoke") is None:
+            self._testcase(result=self)
+        else:
+            # disables tearDown and cleanups for post mortem debugging (see #1890)
+            if self._handle_skip():
+                return
+            self._testcase.debug()
+
+    def _prunetraceback(self, excinfo):
+        Function._prunetraceback(self, excinfo)
+        traceback = excinfo.traceback.filter(
+            lambda x: not x.frame.f_globals.get("__unittest")
+        )
+        if traceback:
+            excinfo.traceback = traceback
+
+
+@hookimpl(tryfirst=True)
+def pytest_runtest_makereport(item, call):
+    if isinstance(item, TestCaseFunction):
+        if item._excinfo:
+            call.excinfo = item._excinfo.pop(0)
+            try:
+                del call.result
+            except AttributeError:
+                pass
+
+
+# twisted trial support
+
+
+@hookimpl(hookwrapper=True)
+def pytest_runtest_protocol(item):
+    if isinstance(item, TestCaseFunction) and "twisted.trial.unittest" in sys.modules:
+        ut = sys.modules["twisted.python.failure"]
+        Failure__init__ = ut.Failure.__init__
+        check_testcase_implements_trial_reporter()
+
+        def excstore(
+            self, exc_value=None, exc_type=None, exc_tb=None, captureVars=None
+        ):
+            if exc_value is None:
+                self._rawexcinfo = sys.exc_info()
+            else:
+                if exc_type is None:
+                    exc_type = type(exc_value)
+                self._rawexcinfo = (exc_type, exc_value, exc_tb)
+            try:
+                Failure__init__(
+                    self, exc_value, exc_type, exc_tb, captureVars=captureVars
+                )
+            except TypeError:
+                Failure__init__(self, exc_value, exc_type, exc_tb)
+
+        ut.Failure.__init__ = excstore
+        yield
+        ut.Failure.__init__ = Failure__init__
+    else:
+        yield
+
+
+def check_testcase_implements_trial_reporter(done=[]):
+    if done:
+        return
+    from zope.interface import classImplements
+    from twisted.trial.itrial import IReporter
+
+    classImplements(TestCaseFunction, IReporter)
+    done.append(1)

src/_pytest/warnings.py

@@ -0,0 +1,111 @@
+from __future__ import absolute_import, division, print_function
+
+import warnings
+from contextlib import contextmanager
+
+import pytest
+
+from _pytest import compat
+
+
+def _setoption(wmod, arg):
+    """
+    Copy of the warning._setoption function but does not escape arguments.
+    """
+    parts = arg.split(":")
+    if len(parts) > 5:
+        raise wmod._OptionError("too many fields (max 5): %r" % (arg,))
+    while len(parts) < 5:
+        parts.append("")
+    action, message, category, module, lineno = [s.strip() for s in parts]
+    action = wmod._getaction(action)
+    category = wmod._getcategory(category)
+    if lineno:
+        try:
+            lineno = int(lineno)
+            if lineno < 0:
+                raise ValueError
+        except (ValueError, OverflowError):
+            raise wmod._OptionError("invalid lineno %r" % (lineno,))
+    else:
+        lineno = 0
+    wmod.filterwarnings(action, message, category, module, lineno)
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("pytest-warnings")
+    group.addoption(
+        "-W",
+        "--pythonwarnings",
+        action="append",
+        help="set which warnings to report, see -W option of python itself.",
+    )
+    parser.addini(
+        "filterwarnings",
+        type="linelist",
+        help="Each line specifies a pattern for "
+        "warnings.filterwarnings. "
+        "Processed after -W and --pythonwarnings.",
+    )
+
+
+@contextmanager
+def catch_warnings_for_item(item):
+    """
+    catches the warnings generated during setup/call/teardown execution
+    of the given item and after it is done posts them as warnings to this
+    item.
+    """
+    args = item.config.getoption("pythonwarnings") or []
+    inifilters = item.config.getini("filterwarnings")
+    with warnings.catch_warnings(record=True) as log:
+        for arg in args:
+            warnings._setoption(arg)
+
+        for arg in inifilters:
+            _setoption(warnings, arg)
+
+        for mark in item.iter_markers(name="filterwarnings"):
+            for arg in mark.args:
+                warnings._setoption(arg)
+
+        yield
+
+        for warning in log:
+            warn_msg = warning.message
+            unicode_warning = False
+
+            if compat._PY2 and any(
+                isinstance(m, compat.UNICODE_TYPES) for m in warn_msg.args
+            ):
+                new_args = []
+                for m in warn_msg.args:
+                    new_args.append(
+                        compat.ascii_escaped(m)
+                        if isinstance(m, compat.UNICODE_TYPES)
+                        else m
+                    )
+                unicode_warning = list(warn_msg.args) != new_args
+                warn_msg.args = new_args
+
+            msg = warnings.formatwarning(
+                warn_msg,
+                warning.category,
+                warning.filename,
+                warning.lineno,
+                warning.line,
+            )
+            item.warn("unused", msg)
+
+            if unicode_warning:
+                warnings.warn(
+                    "Warning is using unicode non convertible to ascii, "
+                    "converting to a safe representation:\n  %s" % msg,
+                    UnicodeWarning,
+                )
+
+
+@pytest.hookimpl(hookwrapper=True)
+def pytest_runtest_protocol(item):
+    with catch_warnings_for_item(item):
+        yield

src/pytest.py

@@ -0,0 +1,73 @@
+# PYTHON_ARGCOMPLETE_OK
+"""
+pytest: unit and functional testing with Python.
+"""
+
+
+# else we are imported
+
+from _pytest.config import main, UsageError, cmdline, hookspec, hookimpl
+from _pytest.fixtures import fixture, yield_fixture
+from _pytest.assertion import register_assert_rewrite
+from _pytest.freeze_support import freeze_includes
+from _pytest import __version__
+from _pytest.debugging import pytestPDB as __pytestPDB
+from _pytest.recwarn import warns, deprecated_call
+from _pytest.outcomes import fail, skip, importorskip, exit, xfail
+from _pytest.mark import MARK_GEN as mark, param
+from _pytest.main import Session
+from _pytest.nodes import Item, Collector, File
+from _pytest.fixtures import fillfixtures as _fillfuncargs
+from _pytest.python import Package, Module, Class, Instance, Function, Generator
+
+from _pytest.python_api import approx, raises
+
+set_trace = __pytestPDB.set_trace
+
+__all__ = [
+    "main",
+    "UsageError",
+    "cmdline",
+    "hookspec",
+    "hookimpl",
+    "__version__",
+    "register_assert_rewrite",
+    "freeze_includes",
+    "set_trace",
+    "warns",
+    "deprecated_call",
+    "fixture",
+    "yield_fixture",
+    "fail",
+    "skip",
+    "xfail",
+    "importorskip",
+    "exit",
+    "mark",
+    "param",
+    "approx",
+    "_fillfuncargs",
+    "Item",
+    "File",
+    "Collector",
+    "Package",
+    "Session",
+    "Module",
+    "Class",
+    "Instance",
+    "Function",
+    "Generator",
+    "raises",
+]
+
+if __name__ == "__main__":
+    # if run as a script or by 'python -m pytest'
+    # we trigger the below "else" condition by the following import
+    import pytest
+
+    raise SystemExit(pytest.main())
+else:
+
+    from _pytest.compat import _setup_collect_fakemodule
+
+    _setup_collect_fakemodule()