Repository: pypa/pip
File: src/pip/_internal/metadata/importlib/_envs.py (Python)

Code before:
    higher precedence one if the caller is not careful.

    Eventually we probably want to make it possible to see lower precedence
    installations as well. It's useful feature, after all.
    """

    FoundResult = tuple[importlib.metadata.Distribution, Optional[BasePath]]

    def __init__(self) -> None:
        self._found_names: set[NormalizedName] = set()

    def _find_impl(self, location: str) -> Iterator[FoundResult]:
        """Find distributions in a location."""
        # Skip looking inside a wheel. Since a package inside a wheel is not
        # always valid (due to .data directories etc.), its .dist-info entry
        # should not be considered an installed distribution.
        if _looks_like_wheel(location):
            return
        # To know exactly where we find a distribution, we have to feed in the
        # paths one by one, instead of dumping the list to importlib.metadata.
        for dist in importlib.metadata.distributions(path=[location]):
            info_location = get_info_location(dist)
            try:
                name = get_dist_canonical_name(dist)
                distribution = Distribution(dist, info_location, None)
                getattr(distribution, "version")
            except BadMetadata as e:
                logger.warning("Skipping %s due to %s", info_location, e.reason)
                continue
            if name in self._found_names:
                continue
            self._found_names.add(name)
            yield dist, info_location

    def find(self, location: str) -> Iterator[BaseDistribution]:
        """Find distributions in a location.

        The path can be either a directory, or a ZIP archive.
        """
        for dist, info_location in self._find_impl(location):
            if info_location is None:
                installed_location: BasePath | None = None
            else:
                installed_location = info_location.parent
            yield Distribution(dist, info_location, installed_location)

    def find_legacy_editables(self, location: str) -> Iterator[BaseDistribution]:
        """Read location in egg-link files and return distributions in there.

        The path should be a directory; otherwise this returns nothing. This
        follows how setuptools does this for compatibility. The first non-empty

Review comment (bug):
I don't understand why you've added this code, though. The original issue didn't suggest there was anything wrong here, and it's causing errors in cases that currently *aren't* raising an unhandled exception.

Is this simply an over-enthusiastic attempt to catch additional cases of bad data? If so, we'd normally avoid doing things like that, because backward compatibility is critical in a project that's used in as many places as pip. In particular, we have to be *exceptionally* careful to be forgiving in the case of bad data, because there's so much older, often legacy, code out there that we need to continue supporting.

Code after:
    higher precedence one if the caller is not careful.

    Eventually we probably want to make it possible to see lower precedence
    installations as well. It's useful feature, after all.
    """

    FoundResult = tuple[importlib.metadata.Distribution, Optional[BasePath]]

    def __init__(self) -> None:
        self._found_names: set[NormalizedName] = set()

    def _find_impl(self, location: str) -> Iterator[FoundResult]:
        """Find distributions in a location."""
        # Skip looking inside a wheel. Since a package inside a wheel is not
        # always valid (due to .data directories etc.), its .dist-info entry
        # should not be considered an installed distribution.
        if _looks_like_wheel(location):
            return
        # To know exactly where we find a distribution, we have to feed in the
        # paths one by one, instead of dumping the list to importlib.metadata.
        for dist in importlib.metadata.distributions(path=[location]):
            info_location = get_info_location(dist)
            try:
                name = get_dist_canonical_name(dist)
            except BadMetadata as e:
                logger.warning("Skipping %s due to %s", info_location, e.reason)
                continue
            if name in self._found_names:
                continue
            self._found_names.add(name)
            yield dist, info_location

    def find(self, location: str) -> Iterator[BaseDistribution]:
        """Find distributions in a location.

        The path can be either a directory, or a ZIP archive.
        """
        for dist, info_location in self._find_impl(location):
            if info_location is None:
                installed_location: BasePath | None = None
            else:
                installed_location = info_location.parent
            yield Distribution(dist, info_location, installed_location)

    def find_legacy_editables(self, location: str) -> Iterator[BaseDistribution]:
        """Read location in egg-link files and return distributions in there.

        The path should be a directory; otherwise this returns nothing. This
        follows how setuptools does this for compatibility. The first non-empty
        line in the egg-link is read as a path (resolved against the egg-link's
        containing directory if relative). Distributions found at that linked