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I'm not sure if I'm using this wrong but when I define a factory such as:

class UserFactory(factory.django.DjangoModelFactory[User]):
    class Meta:
        model = User

I get the following error:

Class 'FactoryMetaClass' does not define '__getitem__', so the '[]' operator cannot be used on its instances

I understand why the error occurs, but I'm not sure what the intended solution is. Since DjangoModelFactory is generic in the stubs, what's the intended usage if DjangoModelFactory isn't actually able to support getitem? Should I monkeypatch FactoryMetaClass?

I am getting a lot of this errors:

error: "Callable[[VarArg(Any), KwArg(Any)], NoReturn]" has no attribute "create"  [attr-defined]
error: "Callable[[VarArg(Any), KwArg(Any)], NoReturn]" has no attribute "create_batch"  [attr-defined]

when apply the type to DjangoModelFactory

I have factories like:

class UserFactory(factory.django.DjangoModelFactory):
    class Meta:
        model = User

    username = factory.Sequence(lambda n: f"{_faker.user_name()}_{n:08}")
    first_name = factory.Faker("first_name")
    last_name = factory.Faker("last_name")
    email = factory.Faker("ascii_safe_email")

with mypy 0.982 I get:

$ mypy --show-error-codes .
blog/factories.py:28: error: Need type annotation for "first_name"  [var-annotated]
blog/factories.py:29: error: Need type annotation for "last_name"  [var-annotated]
blog/factories.py:30: error: Need type annotation for "email"  [var-annotated]

so all the factory.Faker fields have a problem

I can guess this is probably due to the way factory.Faker itself is implemented - the type of the faker depends on the value of the string arg and there's no way for type info from faker itself to flow through that interface.

I guess the only way for that to work would be to tediously define an @overload with Literal[<method name>] for each faker method? Maybe that's not even possible either.

Currently, if I use the factory class directly to create an object, it's type hinted as the factory class:

user = UserFactory()
reveal_type(user)  # UserFactory
type(user) # User

I think this might be because the return value of BaseFactory.__new__ is annotated with Self rather than T?