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Metaclass defined class attribute raise "name-defined" error when used as a type
Using a Metaclass to define dynamic class (not instance) attributes raises name-defined error when trying to use an attribute as a type.
To Reproduce
Gist URL: https://gist.github.com/mypy-play/bb0277c6f339cbf374a1d2288cb7d5e6
Playground URL: https://mypy-play.net/?mypy=latest&python=3.12&gist=bb0277c6f339cbf374a1d2288cb7d5e6
from enum import Enum
class Message:
class Direction(Enum):
IN = "IN"
OUT = "OUT"
class MetaProtoWrapper(type):
def __getattribute__(cls, name: str):
try:
return super().__getattribute__(name)
except AttributeError:
return getattr(cls.Meta.protocol_buffer_type, name)
class ProtoWrapper(metaclass=MetaProtoWrapper):
class Meta:
protocol_buffer_type = Message
direction_in = ProtoWrapper.Direction.IN # OK
direction_in: ProtoWrapper.Direction = ProtoWrapper.Direction.IN # Name "ProtoWrapper.Direction" is not defined [name-defined]
Expected Behavior
ProtoWrapper.Direction should be a valid type
Actual Behavior
ProtoWrapper.Direction raises name-defined error
Your Environment
- Mypy version used:
mypy 1.10.0 (compiled: yes) - Mypy command-line flags: NA
- Mypy configuration options from
mypy.ini(and other config files): NA - Python version used: 3.12