pytest2/src/_pytest/_io/terminalwriter.py

207 lines
6.7 KiB
Python

"""Helper functions for writing to terminals and files."""
import os
import shutil
import sys
import unicodedata
from functools import lru_cache
from typing import Optional
from typing import Sequence
from typing import TextIO
# This code was initially copied from py 1.8.1, file _io/terminalwriter.py.
def get_terminal_width() -> int:
width, _ = shutil.get_terminal_size(fallback=(80, 24))
# The Windows get_terminal_size may be bogus, let's sanify a bit.
if width < 40:
width = 80
return width
@lru_cache(100)
def char_width(c: str) -> int:
# Fullwidth and Wide -> 2, all else (including Ambiguous) -> 1.
return 2 if unicodedata.east_asian_width(c) in ("F", "W") else 1
def get_line_width(text: str) -> int:
text = unicodedata.normalize("NFC", text)
return sum(char_width(c) for c in text)
def should_do_markup(file: TextIO) -> bool:
if os.environ.get("PY_COLORS") == "1":
return True
if os.environ.get("PY_COLORS") == "0":
return False
return (
hasattr(file, "isatty")
and file.isatty()
and os.environ.get("TERM") != "dumb"
and not (sys.platform.startswith("java") and os._name == "nt")
)
class TerminalWriter:
_esctable = dict(
black=30,
red=31,
green=32,
yellow=33,
blue=34,
purple=35,
cyan=36,
white=37,
Black=40,
Red=41,
Green=42,
Yellow=43,
Blue=44,
Purple=45,
Cyan=46,
White=47,
bold=1,
light=2,
blink=5,
invert=7,
)
def __init__(self, file: Optional[TextIO] = None) -> None:
if file is None:
file = sys.stdout
if hasattr(file, "isatty") and file.isatty() and sys.platform == "win32":
try:
import colorama
except ImportError:
pass
else:
file = colorama.AnsiToWin32(file).stream
assert file is not None
self._file = file
self.hasmarkup = should_do_markup(file)
self._current_line = ""
self._terminal_width = None # type: Optional[int]
@property
def fullwidth(self) -> int:
if self._terminal_width is not None:
return self._terminal_width
return get_terminal_width()
@fullwidth.setter
def fullwidth(self, value: int) -> None:
self._terminal_width = value
@property
def width_of_current_line(self) -> int:
"""Return an estimate of the width so far in the current line."""
return get_line_width(self._current_line)
def markup(self, text: str, **markup: bool) -> str:
for name in markup:
if name not in self._esctable:
raise ValueError("unknown markup: {!r}".format(name))
if self.hasmarkup:
esc = [self._esctable[name] for name, on in markup.items() if on]
if esc:
text = "".join("\x1b[%sm" % cod for cod in esc) + text + "\x1b[0m"
return text
def sep(
self,
sepchar: str,
title: Optional[str] = None,
fullwidth: Optional[int] = None,
**markup: bool
) -> None:
if fullwidth is None:
fullwidth = self.fullwidth
# the goal is to have the line be as long as possible
# under the condition that len(line) <= fullwidth
if sys.platform == "win32":
# if we print in the last column on windows we are on a
# new line but there is no way to verify/neutralize this
# (we may not know the exact line width)
# so let's be defensive to avoid empty lines in the output
fullwidth -= 1
if title is not None:
# we want 2 + 2*len(fill) + len(title) <= fullwidth
# i.e. 2 + 2*len(sepchar)*N + len(title) <= fullwidth
# 2*len(sepchar)*N <= fullwidth - len(title) - 2
# N <= (fullwidth - len(title) - 2) // (2*len(sepchar))
N = max((fullwidth - len(title) - 2) // (2 * len(sepchar)), 1)
fill = sepchar * N
line = "{} {} {}".format(fill, title, fill)
else:
# we want len(sepchar)*N <= fullwidth
# i.e. N <= fullwidth // len(sepchar)
line = sepchar * (fullwidth // len(sepchar))
# in some situations there is room for an extra sepchar at the right,
# in particular if we consider that with a sepchar like "_ " the
# trailing space is not important at the end of the line
if len(line) + len(sepchar.rstrip()) <= fullwidth:
line += sepchar.rstrip()
self.line(line, **markup)
def write(self, msg: str, *, flush: bool = False, **markup: bool) -> None:
if msg:
current_line = msg.rsplit("\n", 1)[-1]
if "\n" in msg:
self._current_line = current_line
else:
self._current_line += current_line
msg = self.markup(msg, **markup)
self._file.write(msg)
if flush:
self.flush()
def line(self, s: str = "", **markup: bool) -> None:
self.write(s, **markup)
self.write("\n")
def flush(self) -> None:
self._file.flush()
def _write_source(self, lines: Sequence[str], indents: Sequence[str] = ()) -> None:
"""Write lines of source code possibly highlighted.
Keeping this private for now because the API is clunky. We should discuss how
to evolve the terminal writer so we can have more precise color support, for example
being able to write part of a line in one color and the rest in another, and so on.
"""
if indents and len(indents) != len(lines):
raise ValueError(
"indents size ({}) should have same size as lines ({})".format(
len(indents), len(lines)
)
)
if not indents:
indents = [""] * len(lines)
source = "\n".join(lines)
new_lines = self._highlight(source).splitlines()
for indent, new_line in zip(indents, new_lines):
self.line(indent + new_line)
def _highlight(self, source: str) -> str:
"""Highlight the given source code if we have markup support."""
if not self.hasmarkup:
return source
try:
from pygments.formatters.terminal import TerminalFormatter
from pygments.lexers.python import PythonLexer
from pygments import highlight
except ImportError:
return source
else:
highlighted = highlight(
source, PythonLexer(), TerminalFormatter(bg="dark")
) # type: str
return highlighted