Make enums idempotent #19669
Description
Feature
Currently, passing an enum into its own constructor forgets its value:
from enum import IntEnum class Foo(IntEnum): x = 0 y = 1 reveal_type(Foo(Foo.x)) # reveals Foo, not Foo.x reveal_type(Foo.__new__) # "def [Self <: IntEnum] (cls: type[Self], value: builtins.int) -> Self" reveal_type(Foo.__init__) # "def (self: builtins.object)"Pitch
It should be straightforward to synthesize a signature that makes Foo(Foo.x) inferred as Foo.x.