Class StyleGuideManager

src/flake8/style_guide.py:202–292

Manage multiple style guides for a single run.

class StyleGuideManager:
    """Manage multiple style guides for a single run."""

    def __init__(
        self,
        options: argparse.Namespace,
        formatter: base_formatter.BaseFormatter,
        decider: DecisionEngine | None = None,
    ) -> None:
        """Initialize our StyleGuide.

        .. todo:: Add parameter documentation.
        """
        self.options = options
        self.formatter = formatter
        self.stats = statistics.Statistics()
        self.decider = decider or DecisionEngine(options)
        self.style_guides: list[StyleGuide] = []
        self.default_style_guide = StyleGuide(
            options, formatter, self.stats, decider=decider,
        )
        self.style_guides = [
            self.default_style_guide,
            *self.populate_style_guides_with(options),
        ]

        self.style_guide_for = functools.cache(self._style_guide_for)

    def populate_style_guides_with(
        self, options: argparse.Namespace,
    ) -> Generator[StyleGuide]:
        """Generate style guides from the per-file-ignores option.

        :param options:
            The original options parsed from the CLI and config file.
        :returns:
            A copy of the default style guide with overridden values.
        """
        per_file = utils.parse_files_to_codes_mapping(options.per_file_ignores)
        for filename, violations in per_file:
            yield self.default_style_guide.copy(
                filename=filename, extend_ignore_with=violations,
            )

    def _style_guide_for(self, filename: str) -> StyleGuide:
        """Find the StyleGuide for the filename in particular."""
        return max(
            (g for g in self.style_guides if g.applies_to(filename)),
            key=lambda g: len(g.filename or ""),
        )

    @contextlib.contextmanager
    def processing_file(self, filename: str) -> Generator[StyleGuide]:
        """Record the fact that we're processing the file's results."""
        guide = self.style_guide_for(filename)
        with guide.processing_file(filename):
            yield guide