Method compare_stable

mypy/options.py:539–548

Compare options in a way that is stable for snapshot() -> apply_changes() roundtrip. This is needed because apply_changes() has non-trivial effects for some flags, so Options().apply_changes(options.snapshot()) may result in a (slightly) different object.

(self, other_snapshot: dict[str, object])

        return new_options

    def compare_stable(self, other_snapshot: dict[str, object]) -> bool:
        """Compare options in a way that is stable for snapshot() -> apply_changes() roundtrip.

        This is needed because apply_changes() has non-trivial effects for some flags, so
        Options().apply_changes(options.snapshot()) may result in a (slightly) different object.
        """
        return (
            Options().apply_changes(self.snapshot()).snapshot()
            == Options().apply_changes(other_snapshot).snapshot()
        )

    def build_per_module_cache(self) -> None:
        self._per_module_cache = {}