enum.Flag ignores bitwise operator methods from mixins

[gswifort]

When I define methods ('__or__', '__and__', '__xor__', '__ror__', '__rand__', '__rxor__', '__invert__')
directly in the class inheriting from enum.Flag, these methods are "added" (mro) to the members, however, if the method is defined in the mixin, the methods defined in enum.Flag are added (e.g. Flag.__or__). I would expect methods to be called from mixin.

from enum import Flag


class Mixin:
    def __or__(self, value): ...


class MyFlag(Mixin, Flag):
    pass


class MyFlag2(Flag):
    def __or__(self, value): ...


print(MyFlag.__or__.__qualname__)  # Flag.__or__, I would expect Mixin.__or__
print(MyFlag2.__or__.__qualname__)  # MyFlag2.__or__ - GOOD

cpython/Lib/enum.py

Lines 610 to 619 in 0898354

	if Flag is not None and issubclass(enum_class, Flag):
	for name in (
	'__or__', '__and__', '__xor__',
	'__ror__', '__rand__', '__rxor__',
	'__invert__'
	):
	if name not in classdict:
	enum_method = getattr(Flag, name)
	setattr(enum_class, name, enum_method)
	classdict[name] = enum_method

[pygeek]

super().__or__()

[gswifort]

super().__or__()

Yes, it is a workaround, but I use mixins so as not to add the method in all derived classes. It's easier to add them in __init_subclass__:

class Mixin:

    def __or__(self, value): ...

    def __init_subclass__(cls) -> None:
        setattr(cls, "__or__", Mixin.__or__)