ChoiceField's choices and Enum produces `arg-type` mypy error

[sshishov]

Bug report

Hi @sobolevn @asottile-sentry , This is more like a question.

After some change mypy start producing some error and this error does make sense. Therefore I need the proper suggestion from the experienced guys!

What's wrong

Before this change (#454) we were doing this:

class MyEnum(enum.StrEnum):
    VALUE_1 = 'value_1'
    VALUE_2 = 'value_2'


MySerializer(drf_serializers.Serializer):
    my_choices = drf_serializers.ChoiceField(choices=MyEnum, ...)

But after this change we are receiving this mypy error:

error: Argument "choices" to "ChoiceField" has incompatible type "type[MyEnum]"; expected "Sequence[Any]"  [arg-type]

How is that should be

What is the suggested way to fix this issue? Should we somehow convert the value to "sequence"?

    my_choices = drf_serializers.ChoiceField(choices=tuple(MyEnum), ...)

System information

• OS:
• python version: 3.13.5
• django version: 5.2.4
• mypy version: 1.17.1
• django-stubs version: 5.2.2

It would nice to hear your suggestions, guys!

[intgr]

Indeed, this was changed in DRF-stubs in

• represent choices in ChoiceField as Sequence #686

Looks like DRF passes the choices= argument to to_choices_dict(), which would just iterate over items of the enum. https://github.com/encode/django-rest-framework/blob/a7d050f5b3388ed9dc69c7770fdbd9654d4639ae/rest_framework/fields.py#L119

So, either ChoiceField(choices=list(MyEnum), ...) or ChoiceField(choices=tuple(MyEnum), ...) should work and produce the same end result.

[sshishov]

@intgr good suggestion.

If this is the recommended way (at least by now) to handle enums in choices, then let's close this question and in separate comment indicate that enums should be handled this way.

Thank you for the clarification.