add new parameters:

xfail(run=False) will not run expected-to-fail tests
xfail(reason=True) will report the specified reason

--HG--
branch : trunk

CHANGELOG

@@ -14,6 +14,9 @@ Changes between 1.2.1 and 1.3.0 (release pending)
 - new pytest_pycollect_makemodule(path, parent) hook for
   allowing customization of the Module collection object for a 
   matching test module. 
+- extend py.test.mark.xfail to accept two more keyword arg parameters:
+  ``xfail(run=False)`` will not run the decorated test 
+  ``xfail(reason="...")`` will print the reason string when reporting 
 - expose (previously internal) commonly useful methods: 
   py.io.get_terminal_with() -> return terminal width
   py.io.ansi_print(...) -> print colored/bold text on linux/win32

py/_plugin/pytest_skipping.py

@@ -83,10 +83,17 @@ Same as with skipif_ you can also selectively expect a failure
 depending on platform::
 
     @py.test.mark.xfail("sys.version_info >= (3,0)")
-
     def test_function():
         ...
 
+To not run a test and still regard it as "xfailed"::
+
+    @py.test.mark.xfail(..., run=False)
+
+To specify an explicit reason to be shown with xfailure detail::
+
+    @py.test.mark.xfail(..., reason="my reason")
+
 
 skipping on a missing import dependency
 --------------------------------------------------
@@ -123,13 +130,27 @@ import py
 
 
 def pytest_runtest_setup(item):
+    if not isinstance(item, py.test.collect.Function):
+        return
     expr, result = evalexpression(item, 'skipif')
     if result:
         py.test.skip(expr)
+    holder = getattr(item.obj, 'xfail', None)
+    if holder and not holder.kwargs.get('run', True):
+        py.test.skip("<did not run>")
 
 def pytest_runtest_makereport(__multicall__, item, call):
-    if call.when != "call":
+    if not isinstance(item, py.test.collect.Function):
         return
+    if call.when == "setup":
+        holder = getattr(item.obj, 'xfail', None)
+        if holder:
+            rep = __multicall__.execute()
+            reason = holder.kwargs.get("reason", "<no reason given>")
+            rep.keywords['xfail'] = "[not run] " + reason
+            return rep
+        return
+    elif call.when == "call":
         expr, result = evalexpression(item, 'xfail')
         rep = __multicall__.execute()
         if result:
@@ -151,7 +172,7 @@ def pytest_report_teststatus(report):
         if report.skipped:
             return "xfailed", "x", "xfail"
         elif report.failed:
-            return "xpassed", "P", "xpass"
+            return "xpassed", "P", "XPASS"
 
 # called by the terminalreporter instance/plugin
 def pytest_terminal_summary(terminalreporter):
@@ -172,6 +193,9 @@ def show_xfailed(terminalreporter):
             entry = rep.longrepr.reprcrash
             modpath = rep.item.getmodpath(includemodule=True)
             pos = "%s %s:%d: " %(modpath, entry.path, entry.lineno)
+            if rep.keywords['xfail']:
+                reason = rep.keywords['xfail'].strip()
+            else:
                 reason = rep.longrepr.reprcrash.message
                 i = reason.find("\n")
                 if i != -1:

testing/plugin/test_pytest_resultlog.py

@@ -159,6 +159,9 @@ def test_generic(testdir, LineMatcher):
         @py.test.mark.xfail
         def test_xfail():
             assert 0
+        @py.test.mark.xfail(run=False)
+        def test_xfail_norun():
+            assert 0
     """)
     testdir.runpytest("--resultlog=result.log")
     lines = testdir.tmpdir.join("result.log").readlines(cr=0)
@@ -167,5 +170,6 @@ def test_generic(testdir, LineMatcher):
         "F *:test_fail", 
         "s *:test_skip",
         "x *:test_xfail", 
+        "x *:test_xfail_norun", 
     ])
     

testing/plugin/test_pytest_skipping.py

@@ -12,6 +12,30 @@ def test_xfail_not_report_default(testdir):
         "*1 expected failures*--report=xfailed*",
     ])
 
+def test_xfail_not_run(testdir):
+    p = testdir.makepyfile(test_one="""
+        import py
+        @py.test.mark.xfail(run=False, reason="noway")
+        def test_this():
+            assert 0
+        @py.test.mark.xfail("True", run=False, reason="noway")
+        def test_this_true():
+            assert 0
+        @py.test.mark.xfail("False", run=True, reason="huh")
+        def test_this_false():
+            assert 1
+    """)
+    result = testdir.runpytest(p, '-v')
+    result.stdout.fnmatch_lines([
+        "*2 expected failures*--report=xfailed*",
+        "*1 passed*",
+    ])
+    result = testdir.runpytest(p, '--report=xfailed', )
+    result.stdout.fnmatch_lines([
+        "*test_one*test_this*not run*noway",
+        "*test_one*test_this_true*not run*noway",
+    ])
+
 def test_skip_not_report_default(testdir):
     p = testdir.makepyfile(test_one="""
         import py