fix problem with TypeVar bound to Model passed as a parameter

django-stubs/contrib/auth/models.pyi

@@ -21,12 +21,6 @@ class Permission(models.Model):
     name: str = ...
     content_type: Any = ...
     codename: str = ...
-    objects: Any = ...
-    class Meta:
-        verbose_name: Any = ...
-        verbose_name_plural: Any = ...
-        unique_together: Any = ...
-        ordering: Any = ...
     def natural_key(self) -> Tuple[str, str, str]: ...
 
 class GroupManager(models.Manager):
@@ -40,10 +34,6 @@ class Group(models.Model):
     id: None
     name: str = ...
     permissions: Any = ...
-    objects: Any = ...
-    class Meta:
-        verbose_name: Any = ...
-        verbose_name_plural: Any = ...
     def natural_key(self): ...
 
 class UserManager(BaseUserManager):
@@ -77,7 +67,6 @@ class AbstractUser(AbstractBaseUser, PermissionsMixin):
     email: str = ...
     is_staff: bool = ...
     date_joined: datetime.datetime = ...
-    objects: Any = ...
     EMAIL_FIELD: str = ...
     USERNAME_FIELD: str = ...
     def clean(self) -> None: ...
@@ -85,9 +74,7 @@ class AbstractUser(AbstractBaseUser, PermissionsMixin):
     def get_short_name(self) -> str: ...
     def email_user(self, subject: str, message: str, from_email: str = ..., **kwargs: Any) -> None: ...
 
-class User(AbstractUser):
-    class Meta(AbstractUser.Meta):
-        swappable: str = ...
+class User(AbstractUser): ...
 
 class AnonymousUser:
     id: Any = ...

django-stubs/db/models/base.pyi

@@ -1,12 +1,14 @@
 from typing import Any, List, Optional, Set, Tuple, Dict
 
-class ModelBase(type):
-    pass
+from django.db.models.manager import Manager
+
+class ModelBase(type): ...
 
 class Model(metaclass=ModelBase):
     class DoesNotExist(Exception):
         pass
     pk: Any = ...
+    objects: Manager[Model]
     def __init__(self, **kwargs) -> None: ...
     def delete(self, using: Any = ..., keep_parents: bool = ...) -> Tuple[int, Dict[str, int]]: ...
     def full_clean(self, exclude: Optional[List[str]] = ..., validate_unique: bool = ...) -> None: ...

django-stubs/db/models/manager.pyi

@@ -3,7 +3,7 @@ from typing import Any, Dict, List, Optional, Tuple, Type, TypeVar
 from django.db.models.base import Model
 from django.db.models.query import QuerySet
 
-_T = TypeVar("_T", bound=Model)
+_T = TypeVar("_T", bound=Model, covariant=True)
 
 class BaseManager(QuerySet[_T]):
     creation_counter: int = ...
@@ -24,7 +24,7 @@ class BaseManager(QuerySet[_T]):
 class Manager(BaseManager[_T]): ...
 
 class RelatedManager(Manager[_T]):
-    def add(self, *objs: _T, bulk: bool = ...) -> None: ...
+    def add(self, *objs: Model, bulk: bool = ...) -> None: ...
     def clear(self) -> None: ...
 
 class ManagerDescriptor:

django-stubs/db/models/query.pyi

@@ -6,7 +6,7 @@ from django.db import models
 from django.db.models import Manager
 from django.db.models.sql.query import Query, RawQuery
 
-_T = TypeVar("_T", bound=models.Model)
+_T = TypeVar("_T", bound=models.Model, covariant=True)
 
 class QuerySet(Iterable[_T], Sized):
     def __init__(

mypy_django_plugin/plugins/models.py

@@ -93,8 +93,13 @@ class InjectAnyAsBaseForNestedMeta(ModelClassInitializer):
 
 
 class AddDefaultObjectsManager(ModelClassInitializer):
+    def is_default_objects_attr(self, sym: SymbolTableNode) -> bool:
+        return sym.fullname == helpers.MODEL_CLASS_FULLNAME + '.' + 'objects'
+
     def run(self) -> None:
-        if 'objects' in self.model_classdef.info.names:
+        existing_objects_sym = self.model_classdef.info.get('objects')
+        if (existing_objects_sym is not None
+            and not self.is_default_objects_attr(existing_objects_sym)):
             return None
 
         if self.is_abstract_model():

test-data/typecheck/models.test

@@ -8,7 +8,7 @@ reveal_type(User.objects.get())  # E: Revealed type is 'main.User*'
 [CASE test_leave_as_is_if_objects_is_set_and_fill_typevars_with_outer_class]
 from django.db import models
 
-class UserManager(models.Manager):
+class UserManager(models.Manager[User]):
     def get_or_404(self) -> User:
         pass
 
@@ -19,3 +19,31 @@ reveal_type(User.objects)  # E: Revealed type is 'main.UserManager'
 reveal_type(User.objects.get())  # E: Revealed type is 'main.User*'
 reveal_type(User.objects.get_or_404())  # E: Revealed type is 'main.User'
 
+[CASE test_model_objects_attribute_present_in_case_of_model_cls_passed_as_parameter]
+from typing import Type
+from django.db import models
+
+class Base:
+    def __init__(self, model_cls: Type[models.Model]):
+        self.model_cls = model_cls
+class MyModel(models.Model):
+    pass
+reveal_type(Base(MyModel).model_cls.objects)  # E: Revealed type is 'django.db.models.manager.Manager[django.db.models.base.Model]'
+
+[CASE test_model_objects_attribute_present_in_case_of_model_cls_passed_as_generic_parameter]
+from typing import TypeVar, Generic, Type
+from django.db import models
+
+_T = TypeVar('_T', bound=models.Model)
+class Base(Generic[_T]):
+    def __init__(self, model_cls: Type[_T]):
+        self.model_cls = model_cls
+        reveal_type(self.model_cls.objects)  # E: Revealed type is 'django.db.models.manager.Manager[django.db.models.base.Model]'
+class MyModel(models.Model):
+    pass
+base_instance = Base(MyModel)
+reveal_type(base_instance.model_cls.objects)  # E: Revealed type is 'django.db.models.manager.Manager[main.MyModel]'
+
+class Child(Base[MyModel]):
+    def method(self) -> None:
+        reveal_type(self.model_cls.objects)  # E: Revealed type is 'django.db.models.manager.Manager[main.MyModel]'