The functional API for Django's enumeration types isn't supported

[kevinmarsh]

Bug report

What's wrong

The functional API for Django's Enumeration types doesn't seem to be supported.

These two run fine:

# Example from https://docs.python.org/3/library/enum.html#functional-api
from enum import Enum
Animal = Enum('Animal', 'ANT BEE CAT DOG')

# Example from: https://docs.djangoproject.com/en/3.2/ref/models/fields/#enumeration-types
from django.db import models
class Vehicle(models.TextChoices):
     CAR = 'C'
     TRUCK = 'T'
     JET_SKI = 'J'

But this raises an error:

# Example from: https://docs.djangoproject.com/en/3.2/ref/models/fields/#enumeration-types
from django.db import models
MedalType = models.TextChoices('MedalType', 'GOLD SILVER BRONZE')

my_file.py:3: error: No overload variant of "TextChoices" matches argument types "str", "str"
my_file.py:3: note: Possible overload variant:
my_file.py:3: note:     def __new__(cls, o: bytes, encoding: str = ..., errors: str = ...) -> TextChoices
my_file.py:3: note:     <1 more non-matching overload not shown>

How is that should be

The resulting enum's type should be the same whether you use the normal class based approach or the functional API approach.

System information

• OS: linux
• python version: 3.9.7
• django version: 3.2.8
• mypy version: 0.910
• django-stubs version: 1.9.0
• django-stubs-ext version: 0.3.1

[adamchainz]

I believe this is due to a Mypy bug: python/mypy#6037 . It sounds like Mypy’s enum support needs extending.

I think we can’t do anything here, so closing, but thank you for the report.