Problem with manager created using .from_queryset() and imported from other module

[ngnpope]

Bug report

When a manager is created using .from_queryset() and imported from another module, it's type is Any, but only when the QuerySet subclass has its generic specified as ["MyModel"].

What's wrong

I took this test case and adapted it to move the NewManager = BaseManager.from_queryset(ModelQuerySet) line into myapp/querysets.py and imported NewManager into myapp/models.py instead of ModelQuerySet.

See this diff: from_queryset-extra-tests.txt

Applying this to the current master results in the following two tests failing:

• from_queryset_using_basemanager_with_manager_imported_from_other_module
• from_queryset_using_manager_with_manager_imported_from_other_module

If I change the following in myapp/querysets.py for these tests then they pass:

-                class ModelQuerySet(models.QuerySet["MyModel"]):
+                class ModelQuerySet(models.QuerySet):

Weird.

As far as I could work out get_dynamic_class_hook is being called for myapp.models.NewManager, but then get_function_hook/get_method_hook doesn't seem to get called for methods on the manager in the failure case.

How is that should be

When NewManager is created using .from_queryset() and is imported from another module it shouldn't resolve to Any when Queryset["MyModel"] is used as the subclass, but should be the same as when only QuerySet is used as the subclass or NewManager is created in myapp/models.py.

System information

• OS:
• python version: 3.9.5
• django version: 3.2.13
• mypy version: 0.961
• django-stubs version: 1.12.0
• django-stubs-ext version: 0.5.0

[flaeppe]

Interestingly enough, the hook is called if I do class ModelQuerySet(models.QuerySet[models.Model]) as well.

[ngnpope]

Hmm. Yes. And it also works if I do class ModelQuerySet(models.QuerySet["models.Model"]), so it's not specifically to do with string annotations. Most likely something to do with the circular dependency and the order things are resolved - maybe we need to defer for an extra pass somewhere?

[flaeppe]

I'm suspecting it has to do with this change: #999 (comment)

Or at least that it takes that path to add the manager. I have a change in #1025 that might resolve it. I could try if that's a correct assumption

[flaeppe]

Yep, seems that it worked. See #1033