Edit File: terminalwriter.py
"""Helper functions for writing to terminals and files.""" import os import shutil import sys from typing import Optional from typing import Sequence from typing import TextIO from .wcwidth import wcswidth from _pytest.compat import final # 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 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 if "NO_COLOR" in os.environ: return False if "FORCE_COLOR" in os.environ: return True return ( hasattr(file, "isatty") and file.isatty() and os.environ.get("TERM") != "dumb" ) @final 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: Optional[int] = None self.code_highlight = True @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 wcswidth(self._current_line) def markup(self, text: str, **markup: bool) -> str: for name in markup: if name not in self._esctable: raise ValueError(f"unknown markup: {name!r}") 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 = f"{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) try: self._file.write(msg) except UnicodeEncodeError: # Some environments don't support printing general Unicode # strings, due to misconfiguration or otherwise; in that case, # print the string escaped to ASCII. # When the Unicode situation improves we should consider # letting the error propagate instead of masking it (see #7475 # for one brief attempt). msg = msg.encode("unicode-escape").decode("ascii") 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.""" from _pytest.config.exceptions import UsageError if not self.hasmarkup or not self.code_highlight: return source try: from pygments.formatters.terminal import TerminalFormatter from pygments.lexers.python import PythonLexer from pygments import highlight import pygments.util except ImportError: return source else: try: highlighted: str = highlight( source, PythonLexer(), TerminalFormatter( bg=os.getenv("PYTEST_THEME_MODE", "dark"), style=os.getenv("PYTEST_THEME"), ), ) return highlighted except pygments.util.ClassNotFound: raise UsageError( "PYTEST_THEME environment variable had an invalid value: '{}'. " "Only valid pygment styles are allowed.".format( os.getenv("PYTEST_THEME") ) ) except pygments.util.OptionError: raise UsageError( "PYTEST_THEME_MODE environment variable had an invalid value: '{}'. " "The only allowed values are 'dark' and 'light'.".format( os.getenv("PYTEST_THEME_MODE") ) )