Break what apparently is a cycle involving custom User model and QuerySet.as_manager()

[sterliakov]

Break a cycle resulting in [django-manager-missing]

I'm not sure if my treatment is correct, perhaps I'm just treating symptoms of some deeper problem. However, this at least makes a test case extracted from my real system pass, and removes a dozen of django-manager-missing errors in my code (actually all of them!).

See the contributed test case for details - I don't really see how to summarize it any better.

There seems to be some cycle during semanal, where base_as_manager.type remains None during all iterations (yes, I tried deferring first). This seems to only affect the base QuerySet and require custom AUTH_USER_MODEL.

Prior to the fix, the test failed with the following:

main:2: note: Revealed type is "payments.models.UnknownManager[payments.models.Payout]" (diff)
payments/models:10: error: Couldn't resolve related manager 'payouts' for relation 'payments.models.Payout.triggered_by'.  [django-manager-missing] (diff)
payments/models:24: error: Could not resolve manager type for "payments.models.Payout.objects"  [django-manager-missing] (diff)

[sterliakov]

@flaeppe honestly, I don't really like this one - feels like a hack. If you have some time, could you have a look into what might be going on here? I already spent ~2 days here, but can't figure out why QuerySet.as_manager remains unresolved after multiple semanal passes.

[flaeppe]

I'm not sure you can expect something to get fully typed during semantic analysis? I think you need the semantic analysis of types, type analysis or whatever, and then use a hook for when mypy has decided to enter that phase.

I can't say I'm totally sure about this stuff, but perhaps it could be of some help or give some pointers or something

[flaeppe]

I think this looks fine. It adds special treatment to the QuerySet.as_manager method. Apparently because we can't expect it to have gotten types when the get_base_class_hook comes around.

We also add expectations on what its return value is, which is a bit of cheating, but it's not likely to change and a fair compromise.