Bug report

Bug description:

When defining enum members with hashable values (e.g.frozensets), it was previously (prior to 3.13) possible to look those members up by passing in unhashable values (e.g.sets) that compare equal to those original values.
This no longer works as of 3.13 (specificallyGH-112514), since the unhashable argument is now only compared to unhashable enum values. I haven't been able to find any documentation of this change in the What's New or even the changelog, so I'm assuming it's not entirely intended.

Reproducible example:

fromenumimportEnumclassDirections(Enum):DOWN_ONLY=frozenset({"sc"})UP_ONLY=frozenset({"cs"})UNRESTRICTED=frozenset({"sc","cs"})dirs= {"sc"}# in 3.13, this raises ValueErrorthe_dirs=Directions(dirs)assertthe_dirsisDirections.DOWN_ONLY

Note that in this example (which is based onour use case) there's the obvious user-side fix ofDirections(frozenset(dirs)), but if there happens to be another hashable-equal-to-unhashable use case outside of (frozen)sets, such a workaround might not exist.

CPython versions tested on:

3.13

Operating systems tested on:

Windows

Linked PRs

• gh-125710: [Enum] fix hashable<->nonhashable comparisons for member values #125735
• [3.13] gh-125710: [Enum] fix hashable<->nonhashable comparisons for member values (GH-125735) #125851