django-stubs 4.2.7 throws type check error for Group.user_set

[johnthagen]

Bug report

With django-stubs 4.2.6, the following simplified code type checked:

from django.contrib.auth.models import Group, User

group = Group()
group.user_set.add(User(username=""))

But with with 4.2.7:

$ mypy main.py 
main.py:4: error: "Group" has no attribute "user_set"  [attr-defined]
Found 1 error in 1 file (checked 1 source file)

How is that should be

I expect no type check error here. This seems to be a common way to get the Users of a Group:

• https://stackoverflow.com/a/58453760
• https://snakeycode.wordpress.com/2015/03/11/django-get-all-the-users-in-a-group/
• http://digitaldreamer.net/blog/2010/5/10/get-all-users-group-django/

System information

• OS: macOS
• python version: 3.10.13
• django version: 4.2.8
• mypy version: 1.7.1
• django-stubs version: 4.2.7
• django-stubs-ext version: 4.2.7

Configuration

[tool.mypy]
ignore_missing_imports = true
strict = true
disallow_subclassing_any = false
disallow_untyped_decorators = false
warn_return_any = false

plugins = [
    "pydantic.mypy",
    "mypy_django_plugin.main",
]

[tool.django-stubs]
django_settings_module = "config.settings"

[flaeppe]

Hm, we probably don't have cover for when a ManyToManyField is inherited via an abstract model.

django.contrib.auth.models.User inherits PermissionsMixin.groups which is what results in the user_set related manager.