Break what apparently is a cycle involving custom User model and QuerySet.as_manager() (#2377)

Author: sterliakov

mypy_django_plugin/transformers/managers.py

@@ -511,19 +511,24 @@ def _defer() -> None:
     base_as_manager = queryset_info.get("as_manager")
     if base_as_manager is None:
         return
-    base_as_manager_type = get_proper_type(base_as_manager.type)
-    if not isinstance(base_as_manager_type, CallableType):
-        return
-    base_as_manager_ret_type = get_proper_type(base_as_manager_type.ret_type)
-    if not isinstance(base_as_manager_ret_type, Instance):
-        return
 
-    base_ret_type = base_as_manager_ret_type.type
     manager_sym = semanal_api.lookup_fully_qualified_or_none(fullnames.MANAGER_CLASS_FULLNAME)
     if manager_sym is None or not isinstance(manager_sym.node, TypeInfo):
         return _defer()
 
     manager_base = manager_sym.node
+    base_ret_type = manager_base
+
+    if base_as_manager.fullname != f"{fullnames.QUERYSET_CLASS_FULLNAME}.as_manager":
+        base_as_manager_type = get_proper_type(base_as_manager.type)
+        if not isinstance(base_as_manager_type, CallableType):
+            return
+        base_as_manager_ret_type = get_proper_type(base_as_manager_type.ret_type)
+        if not isinstance(base_as_manager_ret_type, Instance):
+            return
+
+        base_ret_type = base_as_manager_ret_type.type
+
     manager_class_name = f"{manager_base.name}From{queryset_info.name}"
     current_module = semanal_api.modules[semanal_api.cur_mod_id]
     existing_sym = current_module.names.get(manager_class_name)

tests/typecheck/managers/querysets/test_as_manager.yml

@@ -431,3 +431,47 @@
                     class MyQuerySet(models.QuerySet):
                         pass
                     objects = MyQuerySet.as_manager()
+
+-   case: queryset_as_manager_foreignkey_cycle
+    main: |
+        from payments.models import Payout
+        reveal_type(Payout.objects)  # N: Revealed type is "payments.models.ManagerFromPayoutQuerySet[payments.models.Payout]"
+
+    custom_settings: |
+        INSTALLED_APPS = ("django.contrib.contenttypes", "django.contrib.auth", "payments", "accounts")
+        AUTH_USER_MODEL = "accounts.Account"
+    files:
+        -   path: payments/__init__.py
+        -   path: payments/models.py
+            content: |
+                from __future__ import annotations
+
+                from typing_extensions import Self
+
+                from django.contrib.auth import get_user_model
+                from django.db import models
+
+                UserModel = get_user_model()
+
+                class Transaction(models.Model):
+                    user = models.ForeignKey(
+                        UserModel, on_delete=models.CASCADE, related_name="transactions"
+                    )
+
+                class PayoutQuerySet(models.QuerySet["Payout"]):
+                    def unapplied(self) -> Self:
+                        return self
+
+                class Payout(models.Model):
+                    triggered_by = models.ForeignKey(
+                        Transaction, on_delete=models.CASCADE, related_name="payouts"
+                    )
+
+                    objects = PayoutQuerySet.as_manager()
+
+        -   path: accounts/__init__.py
+        -   path: accounts/models.py
+            content: |
+                from django.contrib.auth.models import AbstractUser
+
+                class Account(AbstractUser): pass