Make forward descriptors generic

django-stubs/db/models/fields/related_descriptors.pyi

@@ -1,5 +1,5 @@
 from collections.abc import Callable
-from typing import Any, Generic, TypeVar
+from typing import Any, Generic, overload, Self, TypeVar
 
 from django.core.exceptions import ObjectDoesNotExist
 from django.db.models.base import Model
@@ -10,60 +10,75 @@ from django.db.models.fields.reverse_related import ManyToManyRel, OneToOneRel
 from django.db.models.query import QuerySet
 
 _T = TypeVar("_T")
+_ModelT = TypeVar("_ModelT", bound=Model)
 
-class ForwardManyToOneDescriptor:
+class ForwardManyToOneDescriptor(Generic[_ModelT]):
     RelatedObjectDoesNotExist: type[ObjectDoesNotExist]
     field: Field[Any, Any] = ...
     def __init__(self, field_with_rel: Field[Any, Any]) -> None: ...
     def is_cached(self, instance: Model) -> bool: ...
-    def get_queryset(self, **hints: Any) -> QuerySet[Any]: ...
+    def get_queryset(self, **hints: Any) -> QuerySet[_ModelT]: ...
     def get_prefetch_queryset(
-        self, instances: list[Model], queryset: QuerySet[Any] | None = ...
+        self, instances: list[Model], queryset: QuerySet[_ModelT] | None = ...
     ) -> tuple[
-        QuerySet[Any], Callable[..., Any], Callable[..., Any], bool, str, bool
+        QuerySet[_ModelT], Callable[..., Any], Callable[..., Any], bool, str, bool
     ]: ...
-    def get_object(self, instance: Model) -> Model: ...
+    def get_object(self, instance: Model) -> _ModelT: ...
+    @overload
     def __get__(
-        self, instance: Model | None, cls: type[Model] = ...
-    ) -> Model | ForwardManyToOneDescriptor | None: ...
-    def __set__(self, instance: Model, value: Model | None) -> None: ...
+        self, instance: None, cls: type[Model] = ...
+    ) -> Self: ...
+    @overload
+    def __get__(
+        self, instance: Model, cls: type[Model] = ...
+    ) -> _ModelT: ...
+    def __set__(self, instance: Model, value: _ModelT | None) -> None: ...
     def __reduce__(self) -> tuple[Callable[..., Any], tuple[type[Model], str]]: ...
 
-class ForwardOneToOneDescriptor(ForwardManyToOneDescriptor):
+class ForwardOneToOneDescriptor(Generic[_ModelT], ForwardManyToOneDescriptor[_ModelT]):
     RelatedObjectDoesNotExist: type[ObjectDoesNotExist]
     field: OneToOneField[Any]  # pyright: ignore[reportIncompatibleVariableOverride]
-    def get_object(self, instance: Model) -> Model: ...
 
-class ReverseOneToOneDescriptor:
+class ReverseOneToOneDescriptor(Generic[_ModelT]):
     RelatedObjectDoesNotExist: type[ObjectDoesNotExist]
     related: OneToOneRel = ...
     def __init__(self, related: OneToOneRel) -> None: ...
     def is_cached(self, instance: Model) -> bool: ...
-    def get_queryset(self, **hints: Any) -> QuerySet[Any]: ...
+    def get_queryset(self, **hints: Any) -> QuerySet[_ModelT]: ...
     def get_prefetch_queryset(
-        self, instances: list[Model], queryset: QuerySet[Any] | None = ...
+        self, instances: list[Model], queryset: QuerySet[_ModelT] | None = ...
     ) -> tuple[
-        QuerySet[Any], Callable[..., Any], Callable[..., Any], bool, str, bool
+        QuerySet[_ModelT], Callable[..., Any], Callable[..., Any], bool, str, bool
     ]: ...
+    @overload
     def __get__(
-        self, instance: Model | None, cls: type[Model] = ...
-    ) -> Model | ReverseOneToOneDescriptor: ...
-    def __set__(self, instance: Model, value: Model | None) -> None: ...
+        self, instance: None, cls: type[Model] = ...
+    ) -> Self: ...
+    @overload
+    def __get__(
+        self, instance: Model, cls: type[Model] = ...
+    ) -> _ModelT: ...
+    def __set__(self, instance: Model, value: _ModelT | None) -> None: ...
     def __reduce__(self) -> tuple[Callable[..., Any], tuple[type[Model], str]]: ...
 
-class ReverseManyToOneDescriptor:
+class ReverseManyToOneDescriptor(Generic[_ModelT]):
     rel: FieldCacheMixin = ...
     field: FieldCacheMixin = ...
     def __init__(self, rel: FieldCacheMixin) -> None: ...
     def related_manager_cls(self) -> Any: ...
+    @overload
+    def __get__(
+        self, instance: None, cls: type[Model] = ...
+    ) -> Self: ...
+    @overload
     def __get__(
         self, instance: Model | None, cls: type[Model] = ...
-    ) -> ReverseManyToOneDescriptor: ...
+    ) -> _ModelT: ...
     def __set__(self, instance: Model, value: list[Model]) -> Any: ...
 
 def create_reverse_many_to_one_manager(superclass: Any, rel: Any) -> Any: ...
 
-class ManyToManyDescriptor(ReverseManyToOneDescriptor):
+class ManyToManyDescriptor(Generic[_ModelT], ReverseManyToOneDescriptor[_ModelT]):
     field: RelatedField[Any, Any]  # pyright: ignore[reportIncompatibleVariableOverride]
     rel: ManyToManyRel  # pyright: ignore[reportIncompatibleVariableOverride]
     reverse: bool = ...