3.11.5 Regression: Flags with custom __new__ can't be iterated #108682
Description
Bug report
Checklist
- I am confident this is a bug in CPython, not a bug in a third-party project
- I have searched the CPython issue tracker,
and am confident this bug has not been reported before
CPython versions tested on:
3.11
Operating systems tested on:
Linux
Output from running 'python -VV' on the command line:
Python 3.11.5 (main, Aug 25 2023, 23:47:33) [GCC 12.2.0]
A clear and concise description of the bug:
A behavior of Flag changed in python 3.11.5. When Flag with custom __new__ is used in combination with functional API, it's members can't be retrieved by iteration over the class.
MWE:
from enum import IntFlag
Perm = IntFlag('Perm', {'R': 4, 'W': 2, 'X': 1})
print(tuple(Perm))
class LabeledFlag(IntFlag):
def __new__(cls, value: int, label: str):
obj = super().__new__(cls, value)
obj._value_ = value
obj.label = label
return obj
LabeledPerm = LabeledFlag('LabeledPerm', {'R': (4, 'Read'), 'W': (2, 'Write'), 'X': (1, 'Exec')})
print(tuple(LabeledPerm))The output in python 3.11.4:
(<Perm.R: 4>, <Perm.W: 2>, <Perm.X: 1>)
(<LabeledPerm.R: 4>, <LabeledPerm.W: 2>, <LabeledPerm.X: 1>)
The output in python 3.11.5:
(<Perm.R: 4>, <Perm.W: 2>, <Perm.X: 1>)
()
I suspect this commit to introduce the regression: 59f009e
A workaround for 3.11.5:
class LabeledFlag(IntFlag):
def __new__(cls, value: int, label: str):
obj = super().__new__(cls, value)
obj._value_ = value
obj.label = label
return obj
@classmethod
def _missing_(cls, value):
pseudo_member = super(_DnskeyFlagBase, cls)._missing_(value)
if value in cls._value2member_map_ and pseudo_member.name is None:
cls._value2member_map_.pop(value)
return pseudo_member