Set custom queryset methods as manager attrs instead of method copies (#820)

Instead of copying methods over from a QuerySet passed to a basemanager
when invoking '<BaseManager>.from_queryset', any QuerySet methods are
declared as attributes on the manager.

This allows us to properly lookup any QuerySet method types via a
'get_attribute_hook' and will thus remove disorienting phantom errors
occuring from mypy trying to resolve types only existing in the module
where the _original_ (and real) queryset method was declared.

mypy_django_plugin/lib/helpers.py

@@ -34,7 +34,7 @@ from mypy.plugin import (
     MethodContext,
     SemanticAnalyzerPluginInterface,
 )
-from mypy.plugins.common import add_method
+from mypy.plugins.common import add_method_to_class
 from mypy.semanal import SemanticAnalyzer
 from mypy.types import AnyType, CallableType, Instance, NoneTyp, TupleType
 from mypy.types import Type as MypyType
@@ -383,7 +383,9 @@ def copy_method_to_another_class(
             return
 
         arguments, return_type = build_unannotated_method_args(method_node)
-        add_method(ctx, new_method_name, args=arguments, return_type=return_type, self_type=self_type)
+        add_method_to_class(
+            semanal_api, ctx.cls, new_method_name, args=arguments, return_type=return_type, self_type=self_type
+        )
         return
 
     method_type = method_node.type
@@ -421,7 +423,9 @@ def copy_method_to_another_class(
         argument.set_line(original_argument)
         arguments.append(argument)
 
-    add_method(ctx, new_method_name, args=arguments, return_type=return_type, self_type=self_type)
+    add_method_to_class(
+        semanal_api, ctx.cls, new_method_name, args=arguments, return_type=return_type, self_type=self_type
+    )
 
 
 def add_new_manager_base(api: SemanticAnalyzerPluginInterface, fullname: str) -> None:

mypy_django_plugin/main.py

@@ -24,7 +24,10 @@ import mypy_django_plugin.transformers.orm_lookups
 from mypy_django_plugin.django.context import DjangoContext
 from mypy_django_plugin.lib import fullnames, helpers
 from mypy_django_plugin.transformers import fields, forms, init_create, meta, querysets, request, settings
-from mypy_django_plugin.transformers.managers import create_new_manager_class_from_from_queryset_method
+from mypy_django_plugin.transformers.managers import (
+    create_new_manager_class_from_from_queryset_method,
+    resolve_manager_method,
+)
 from mypy_django_plugin.transformers.models import (
     handle_annotated_type,
     process_model_class,
@@ -302,6 +305,7 @@ class NewSemanalDjangoPlugin(Plugin):
                 mypy_django_plugin.transformers.orm_lookups.typecheck_queryset_filter,
                 django_context=self.django_context,
             )
+
         return None
 
     def get_base_class_hook(self, fullname: str) -> Optional[Callable[[ClassDefContext], None]]:
@@ -330,6 +334,13 @@ class NewSemanalDjangoPlugin(Plugin):
             return partial(request.set_auth_user_model_as_type_for_request_user, django_context=self.django_context)
         if info and info.has_base(fullnames.ABSTRACT_USER_MODEL_FULLNAME) and attr_name in ("is_staff", "is_active"):
             return partial(set_auth_user_model_boolean_fields, django_context=self.django_context)
+        if (
+            info
+            and info.has_base(fullnames.BASE_MANAGER_CLASS_FULLNAME)
+            and class_name in self._get_current_manager_bases()
+        ):
+            return partial(resolve_manager_method, django_context=self.django_context)
+
         return None
 
     def get_type_analyze_hook(self, fullname: str) -> Optional[Callable[[AnalyzeTypeContext], MypyType]]:

mypy_django_plugin/transformers/managers.py

@@ -1,14 +1,137 @@
-from mypy.checker import fill_typevars
-from mypy.nodes import GDEF, Decorator, FuncDef, MemberExpr, NameExpr, RefExpr, StrExpr, SymbolTableNode, TypeInfo
-from mypy.plugin import ClassDefContext, DynamicClassDefContext
-from mypy.types import CallableType, Instance, TypeVarType, UnboundType, get_proper_type
+from typing import Optional, Union
 
+from mypy.checker import TypeChecker, fill_typevars
+from mypy.nodes import (
+    GDEF,
+    Decorator,
+    FuncBase,
+    FuncDef,
+    MemberExpr,
+    NameExpr,
+    OverloadedFuncDef,
+    RefExpr,
+    StrExpr,
+    SymbolTableNode,
+    TypeInfo,
+    Var,
+)
+from mypy.plugin import AttributeContext, ClassDefContext, DynamicClassDefContext
+from mypy.types import AnyType, CallableType, Instance, ProperType
+from mypy.types import Type as MypyType
+from mypy.types import TypeOfAny, TypeVarType, UnboundType, get_proper_type
+
+from mypy_django_plugin.django.context import DjangoContext
 from mypy_django_plugin.lib import fullnames, helpers
 
 
+def get_method_type_from_dynamic_manager(
+    api: TypeChecker, method_name: str, manager_type_info: TypeInfo
+) -> Optional[ProperType]:
+    """
+    Attempt to resolve a method on a manager that was built from '.from_queryset'
+    """
+    if (
+        "django" not in manager_type_info.metadata
+        or "from_queryset_manager" not in manager_type_info.metadata["django"]
+    ):
+        # Manager isn't dynamically added
+        return None
+
+    queryset_fullname = manager_type_info.metadata["django"]["from_queryset_manager"]
+    assert isinstance(queryset_fullname, str)
+    queryset_info = helpers.lookup_fully_qualified_typeinfo(api, queryset_fullname)
+    assert queryset_info is not None
+
+    def get_funcdef_type(definition: Union[FuncBase, Decorator, None]) -> Optional[ProperType]:
+        # TODO: Handle @overload?
+        if isinstance(definition, FuncBase) and not isinstance(definition, OverloadedFuncDef):
+            return definition.type
+        elif isinstance(definition, Decorator):
+            return definition.func.type
+        return None
+
+    method_type = get_funcdef_type(queryset_info.get_method(method_name))
+    if method_type is None:
+        return None
+
+    assert isinstance(method_type, CallableType)
+    # Drop any 'self' argument as our manager is already initialized
+    return method_type.copy_modified(
+        arg_types=method_type.arg_types[1:],
+        arg_kinds=method_type.arg_kinds[1:],
+        arg_names=method_type.arg_names[1:],
+    )
+
+
+def get_method_type_from_reverse_manager(
+    api: TypeChecker, method_name: str, manager_type_info: TypeInfo
+) -> Optional[ProperType]:
+    """
+    Attempts to resolve a reverse manager's method via the '_default_manager' manager on the related model
+    From Django docs:
+      "By default the RelatedManager used for reverse relations is a subclass of the default manager for that model."
+    Ref: https://docs.djangoproject.com/en/dev/topics/db/queries/#using-a-custom-reverse-manager
+    """
+    is_reverse_manager = (
+        "django" in manager_type_info.metadata and "related_manager_to_model" in manager_type_info.metadata["django"]
+    )
+    if not is_reverse_manager:
+        return None
+
+    related_model_fullname = manager_type_info.metadata["django"]["related_manager_to_model"]
+    assert isinstance(related_model_fullname, str)
+    model_info = helpers.lookup_fully_qualified_typeinfo(api, related_model_fullname)
+    if model_info is None:
+        return None
+
+    # We should _always_ have a '_default_manager' on a model
+    assert "_default_manager" in model_info.names
+    assert isinstance(model_info.names["_default_manager"].node, Var)
+    manager_instance = model_info.names["_default_manager"].node.type
+    return (
+        get_method_type_from_dynamic_manager(api, method_name, manager_instance.type)
+        # TODO: Can we assert on None and Instance?
+        if manager_instance is not None and isinstance(manager_instance, Instance)
+        else None
+    )
+
+
+def resolve_manager_method(ctx: AttributeContext, django_context: DjangoContext) -> MypyType:
+    """
+    A 'get_attribute_hook' that is intended to be invoked whenever the TypeChecker encounters
+    an attribute on a class that has 'django.db.models.BaseManager' as a base.
+    """
+    api = helpers.get_typechecker_api(ctx)
+    # Skip (method) type that is currently something other than Any
+    if not isinstance(ctx.default_attr_type, AnyType):
+        return ctx.default_attr_type
+
+    # (Current state is:) We wouldn't end up here when looking up a method from a custom _manager_.
+    # That's why we only attempt to lookup the method for either a dynamically added or reverse manager.
+    assert isinstance(ctx.context, MemberExpr)
+    method_name = ctx.context.name
+    manager_instance = ctx.type
+    assert isinstance(manager_instance, Instance)
+    method_type = get_method_type_from_dynamic_manager(
+        api, method_name, manager_instance.type
+    ) or get_method_type_from_reverse_manager(api, method_name, manager_instance.type)
+
+    return method_type if method_type is not None else ctx.default_attr_type
+
+
 def create_new_manager_class_from_from_queryset_method(ctx: DynamicClassDefContext) -> None:
+    """
+    Insert a new manager class node for a: '<Name> = <Manager>.from_queryset(<QuerySet>)'.
+    When the assignment expression lives at module level.
+    """
     semanal_api = helpers.get_semanal_api(ctx)
 
+    # Don't redeclare the manager class if we've already defined it.
+    manager_node = semanal_api.lookup_current_scope(ctx.name)
+    if manager_node and isinstance(manager_node.node, TypeInfo):
+        # This is just a deferral run where our work is already finished
+        return
+
     callee = ctx.call.callee
     assert isinstance(callee, MemberExpr)
     assert isinstance(callee.expr, RefExpr)
@@ -54,9 +177,11 @@ def create_new_manager_class_from_from_queryset_method(ctx: DynamicClassDefConte
     new_manager_info.defn.type_vars = base_manager_info.defn.type_vars
     new_manager_info.defn.line = ctx.call.line
     new_manager_info.metaclass_type = new_manager_info.calculate_metaclass_type()
-
-    current_module = semanal_api.cur_mod_node
-    current_module.names[ctx.name] = SymbolTableNode(GDEF, new_manager_info, plugin_generated=True)
+    # Stash the queryset fullname which was passed to .from_queryset
+    # So that our 'resolve_manager_method' attribute hook can fetch the method from that QuerySet class
+    new_manager_info.metadata.setdefault("django", {})
+    new_manager_info.metadata["django"].setdefault("from_queryset_manager", {})
+    new_manager_info.metadata["django"]["from_queryset_manager"] = derived_queryset_fullname
 
     if len(ctx.call.args) > 1:
         expr = ctx.call.args[1]
@@ -66,8 +191,7 @@ def create_new_manager_class_from_from_queryset_method(ctx: DynamicClassDefConte
         custom_manager_generated_name = base_manager_info.name + "From" + derived_queryset_info.name
 
     custom_manager_generated_fullname = ".".join(["django.db.models.manager", custom_manager_generated_name])
-    if "from_queryset_managers" not in base_manager_info.metadata:
-        base_manager_info.metadata["from_queryset_managers"] = {}
+    base_manager_info.metadata.setdefault("from_queryset_managers", {})
     base_manager_info.metadata["from_queryset_managers"][custom_manager_generated_fullname] = new_manager_info.fullname
 
     # So that the plugin will reparameterize the manager when it is constructed inside of a Model definition
@@ -76,13 +200,10 @@ def create_new_manager_class_from_from_queryset_method(ctx: DynamicClassDefConte
     class_def_context = ClassDefContext(cls=new_manager_info.defn, reason=ctx.call, api=semanal_api)
     self_type = fill_typevars(new_manager_info)
     assert isinstance(self_type, Instance)
-    queryset_method_names = []
 
-    # we need to copy all methods in MRO before django.db.models.query.QuerySet
+    # We collect and mark up all methods before django.db.models.query.QuerySet as class members
     for class_mro_info in derived_queryset_info.mro:
         if class_mro_info.fullname == fullnames.QUERYSET_CLASS_FULLNAME:
-            for name, sym in class_mro_info.names.items():
-                queryset_method_names.append(name)
             break
         for name, sym in class_mro_info.names.items():
             if isinstance(sym.node, FuncDef):
@@ -91,10 +212,17 @@ def create_new_manager_class_from_from_queryset_method(ctx: DynamicClassDefConte
                 func_node = sym.node.func
             else:
                 continue
-            helpers.copy_method_to_another_class(
-                class_def_context, self_type, new_method_name=name, method_node=func_node
-            )
 
+            # Insert the queryset method name as a class member. Note that the type of
+            # the method is set as Any. Figuring out the type is the job of the
+            # 'resolve_manager_method' attribute hook, which comes later.
+            #
+            # class BaseManagerFromMyQuerySet(BaseManager):
+            #    queryset_method: Any = ...
+            #
+            helpers.add_new_sym_for_info(new_manager_info, name=name, sym_type=AnyType(TypeOfAny.special_form))
+
+    # we need to copy all methods in MRO before django.db.models.query.QuerySet
     # Gather names of all BaseManager methods
     manager_method_names = []
     for manager_mro_info in new_manager_info.mro:
@@ -150,3 +278,6 @@ def create_new_manager_class_from_from_queryset_method(ctx: DynamicClassDefConte
                 return_type=return_type,
                 original_module_name=class_mro_info.module_name,
             )
+
+    # Insert the new manager (dynamic) class
+    assert semanal_api.add_symbol_table_node(ctx.name, SymbolTableNode(GDEF, new_manager_info, plugin_generated=True))

mypy_django_plugin/transformers/models.py

@@ -68,6 +68,20 @@ class ModelClassInitializer:
             return
         self.run_with_model_cls(model_cls)
 
+    def get_generated_manager_mappings(self, base_manager_fullname: str) -> Dict[str, str]:
+        base_manager_info = self.lookup_typeinfo(base_manager_fullname)
+        if base_manager_info is None or "from_queryset_managers" not in base_manager_info.metadata:
+            return {}
+        return base_manager_info.metadata["from_queryset_managers"]
+
+    def get_generated_manager_info(self, manager_fullname: str, base_manager_fullname: str) -> Optional[TypeInfo]:
+        generated_managers = self.get_generated_manager_mappings(base_manager_fullname)
+        real_manager_fullname = generated_managers.get(manager_fullname)
+        if real_manager_fullname:
+            return self.lookup_typeinfo(real_manager_fullname)
+        # Not a generated manager
+        return None
+
     def run_with_model_cls(self, model_cls):
         raise NotImplementedError("Implement this in subclasses")
 
@@ -179,12 +193,6 @@ class AddManagers(ModelClassInitializer):
     def is_any_parametrized_manager(self, typ: Instance) -> bool:
         return typ.type.fullname in fullnames.MANAGER_CLASSES and isinstance(typ.args[0], AnyType)
 
-    def get_generated_manager_mappings(self, base_manager_fullname: str) -> Dict[str, str]:
-        base_manager_info = self.lookup_typeinfo(base_manager_fullname)
-        if base_manager_info is None or "from_queryset_managers" not in base_manager_info.metadata:
-            return {}
-        return base_manager_info.metadata["from_queryset_managers"]
-
     def create_new_model_parametrized_manager(self, name: str, base_manager_info: TypeInfo) -> Instance:
         bases = []
         for original_base in base_manager_info.bases:
@@ -230,23 +238,25 @@ class AddManagers(ModelClassInitializer):
                 if not self.api.final_iteration:
                     raise exc
                 else:
+                    # On final round, see if we can find info for a generated (dynamic class) manager
                     base_manager_fullname = helpers.get_class_fullname(manager.__class__.__bases__[0])
-                    generated_managers = self.get_generated_manager_mappings(base_manager_fullname)
-                    if manager_fullname not in generated_managers:
-                        # not a generated manager, continue with the loop
-                        continue
-                    real_manager_fullname = generated_managers[manager_fullname]
-                    manager_info = self.lookup_typeinfo(real_manager_fullname)
+                    manager_info = self.get_generated_manager_info(manager_fullname, base_manager_fullname)
                     if manager_info is None:
                         continue
-                    manager_class_name = real_manager_fullname.rsplit(".", maxsplit=1)[1]
+                    _, manager_class_name = manager_info.fullname.rsplit(".", maxsplit=1)
 
             if manager_name not in self.model_classdef.info.names:
                 manager_type = Instance(manager_info, [Instance(self.model_classdef.info, [])])
                 self.add_new_node_to_model_class(manager_name, manager_type)
             else:
-                # creates new MODELNAME_MANAGERCLASSNAME class that represents manager parametrized with current model
-                if not self.has_any_parametrized_manager_as_base(manager_info):
+                # Ending up here could for instance be due to having a custom _Manager_
+                # that is not built from a custom QuerySet. Another example is a
+                # related manager.
+                # Don't interfere with dynamically generated manager classes
+                is_dynamically_generated = "django" in manager_info.metadata and manager_info.metadata["django"].get(
+                    "from_queryset_manager"
+                )
+                if not self.has_any_parametrized_manager_as_base(manager_info) or is_dynamically_generated:
                     continue
 
                 custom_model_manager_name = manager.model.__name__ + "_" + manager_class_name
@@ -262,10 +272,25 @@ class AddManagers(ModelClassInitializer):
 
 class AddDefaultManagerAttribute(ModelClassInitializer):
     def run_with_model_cls(self, model_cls: Type[Model]) -> None:
-        # add _default_manager
-        if "_default_manager" not in self.model_classdef.info.names:
-            default_manager_fullname = helpers.get_class_fullname(model_cls._meta.default_manager.__class__)
+        if "_default_manager" in self.model_classdef.info.names:
+            return None
+
+        default_manager_cls = model_cls._meta.default_manager.__class__
+        default_manager_fullname = helpers.get_class_fullname(default_manager_cls)
+        try:
             default_manager_info = self.lookup_typeinfo_or_incomplete_defn_error(default_manager_fullname)
+        except helpers.IncompleteDefnException as exc:
+            if not self.api.final_iteration:
+                raise exc
+            else:
+                base_manager_fullname = helpers.get_class_fullname(default_manager_cls.__bases__[0])
+                generated_manager_info = self.get_generated_manager_info(
+                    default_manager_fullname, base_manager_fullname
+                )
+                if generated_manager_info is None:
+                    return
+                default_manager_info = generated_manager_info
+
         default_manager = Instance(default_manager_info, [Instance(self.model_classdef.info, [])])
         self.add_new_node_to_model_class("_default_manager", default_manager)
 
@@ -300,6 +325,8 @@ class AddRelatedManagers(ModelClassInitializer):
                     related_manager_info = self.lookup_typeinfo_or_incomplete_defn_error(
                         fullnames.RELATED_MANAGER_CLASS
                     )  # noqa: E501
+                    # TODO: Use default manager instead of 'objects'
+                    # See: https://docs.djangoproject.com/en/dev/topics/db/queries/#using-a-custom-reverse-manager
                     objects = related_model_info.get("objects")
                     if not objects:
                         raise helpers.IncompleteDefnException()
@@ -325,15 +352,10 @@ class AddRelatedManagers(ModelClassInitializer):
                 name = model_cls.__name__ + "_" + related_model_cls.__name__ + "_" + "RelatedManager"
                 bases = [parametrized_related_manager_type, default_manager_type]
                 new_related_manager_info = self.add_new_class_for_current_module(name, bases)
+                new_related_manager_info.metadata["django"] = {"related_manager_to_model": related_model_info.fullname}
 
                 self.add_new_node_to_model_class(attname, Instance(new_related_manager_info, []))
 
-    def get_generated_manager_mappings(self, base_manager_fullname: str) -> Dict[str, str]:
-        base_manager_info = self.lookup_typeinfo(base_manager_fullname)
-        if base_manager_info is None or "from_queryset_managers" not in base_manager_info.metadata:
-            return {}
-        return base_manager_info.metadata["from_queryset_managers"]
-
     def try_generate_related_manager(
         self, related_model_cls: Type[Model], related_model_info: TypeInfo
     ) -> Optional[Instance]:

tests/typecheck/fields/test_related.yml

@@ -684,6 +684,7 @@
         reveal_type(User().orders)  # N: Revealed type is "myapp.models.User_Order_RelatedManager1"
         reveal_type(User().orders.get())  # N: Revealed type is "myapp.models.Order*"
         reveal_type(User().orders.manager_method())  # N: Revealed type is "builtins.int"
+        reveal_type(Product.objects.queryset_method())  # N: Revealed type is "builtins.int"
         reveal_type(Order().products)  # N: Revealed type is "myapp.models.Order_Product_RelatedManager1"
         reveal_type(Order().products.get())  # N: Revealed type is "myapp.models.Product*"
         reveal_type(Order().products.queryset_method())  # N: Revealed type is "builtins.int"

tests/typecheck/managers/querysets/test_from_queryset.yml

@@ -22,6 +22,55 @@
                 class MyModel(models.Model):
                     objects = NewManager()
 
+-   case: from_queryset_queryset_imported_from_other_module
+    main: |
+        from myapp.models import MyModel
+        reveal_type(MyModel.objects)  # N: Revealed type is "myapp.models.NewManager[myapp.models.MyModel]"
+        reveal_type(MyModel.objects)  # N: Revealed type is "myapp.models.NewManager[myapp.models.MyModel]"
+        reveal_type(MyModel.objects.get())  # N: Revealed type is "myapp.models.MyModel*"
+        reveal_type(MyModel.objects.queryset_method())  # N: Revealed type is "myapp.querysets.ModelQuerySet"
+        reveal_type(MyModel.objects.queryset_method_2())  # N: Revealed type is "typing.Iterable[myapp.querysets.Custom]"
+        reveal_type(MyModel.objects.queryset_method_3())  # N: Revealed type is "builtins.str"
+        reveal_type(MyModel.objects.queryset_method_4([]))  # N: Revealed type is "None"
+        reveal_type(MyModel.objects.filter(id=1).queryset_method()) # N: Revealed type is "myapp.querysets.ModelQuerySet"
+        reveal_type(MyModel.objects.filter(id=1)) # N: Revealed type is "myapp.querysets.ModelQuerySet[myapp.models.MyModel*]"
+    installed_apps:
+        - myapp
+    files:
+        -   path: myapp/__init__.py
+        -   path: myapp/querysets.py
+            content: |
+                from typing import TYPE_CHECKING, Iterable, Sequence
+                from django.db import models
+                if TYPE_CHECKING:
+                    from .models import MyModel
+
+                class Custom:
+                    ...
+
+                class ModelQuerySet(models.QuerySet["MyModel"]):
+                    def queryset_method(self) -> "ModelQuerySet":
+                        return self.filter()
+
+                    def queryset_method_2(self) -> Iterable[Custom]:
+                        return []
+
+                    def queryset_method_3(self) -> str:
+                        return 'hello'
+
+                    def queryset_method_4(self, arg: Sequence) -> None:
+                        return None
+
+        -   path: myapp/models.py
+            content: |
+                from django.db import models
+                from django.db.models.manager import BaseManager
+                from .querysets import ModelQuerySet
+
+                NewManager = BaseManager.from_queryset(ModelQuerySet)
+                class MyModel(models.Model):
+                    objects = NewManager()
+
 -   case: from_queryset_with_manager
     main: |
         from myapp.models import MyModel
@@ -48,7 +97,7 @@
     main: |
         from myapp.models import MyModel, NewManager
         reveal_type(NewManager())  # N: Revealed type is "myapp.models.NewManager"
-        reveal_type(MyModel.objects)  # N: Revealed type is "myapp.models.MyModel_NewManager[myapp.models.MyModel]"
+        reveal_type(MyModel.objects)  # N: Revealed type is "myapp.models.NewManager[myapp.models.MyModel]"
         reveal_type(MyModel.objects.get())  # N: Revealed type is "Any"
         reveal_type(MyModel.objects.manager_only_method())  # N: Revealed type is "builtins.int"
         reveal_type(MyModel.objects.manager_and_queryset_method())  # N: Revealed type is "builtins.str"
@@ -74,7 +123,7 @@
     main: |
         from myapp.models import MyModel, NewManager
         reveal_type(NewManager())  # N: Revealed type is "myapp.models.NewManager"
-        reveal_type(MyModel.objects)  # N: Revealed type is "myapp.models.MyModel_NewManager[myapp.models.MyModel]"
+        reveal_type(MyModel.objects)  # N: Revealed type is "myapp.models.NewManager[myapp.models.MyModel]"
         reveal_type(MyModel.objects.get())  # N: Revealed type is "Any"
         reveal_type(MyModel.objects.manager_only_method())  # N: Revealed type is "builtins.int"
         reveal_type(MyModel.objects.manager_and_queryset_method())  # N: Revealed type is "builtins.str"
@@ -187,6 +236,7 @@
         from myapp.models import MyModel
         reveal_type(MyModel().objects)  # N: Revealed type is "myapp.models.NewManager[myapp.models.MyModel]"
         reveal_type(MyModel().objects.queryset_method())  # N: Revealed type is "builtins.str"
+        reveal_type(MyModel.objects.queryset_method_2())  # N: Revealed type is "builtins.int"
     installed_apps:
         - myapp
     files:
@@ -200,6 +250,62 @@
                     def queryset_method(self) -> str:
                         return 'hello'
 
+                    @transaction.atomic
+                    @transaction.atomic
+                    def queryset_method_2(self) -> int:
+                        return 2
+
                 NewManager = models.Manager.from_queryset(ModelQuerySet)
                 class MyModel(models.Model):
                     objects = NewManager()
+
+-   case: from_queryset_model_gets_generated_manager_as_default_manager
+    main: |
+        from myapp.models import MyModel
+        reveal_type(MyModel.objects)  # N: Revealed type is "myapp.models.NewManager[myapp.models.MyModel]"
+        reveal_type(MyModel.objects.queryset_method())  # N: Revealed type is "builtins.str"
+        reveal_type(MyModel._default_manager)  # N: Revealed type is "myapp.models.NewManager[myapp.models.MyModel]"
+    installed_apps:
+        - myapp
+    files:
+        -   path: myapp/__init__.py
+        -   path: myapp/models.py
+            content: |
+                from django.db import models
+
+                class ModelQuerySet(models.QuerySet):
+                    def queryset_method(self) -> str:
+                        return 'hello'
+
+                NewManager = models.Manager.from_queryset(ModelQuerySet)
+                class MyModel(models.Model):
+                    objects = NewManager()
+
+-   case: from_queryset_can_resolve_explicit_any_methods
+    main: |
+        from myapp.models import MyModel
+        reveal_type(MyModel.objects)  # N: Revealed type is "myapp.models.NewManager[myapp.models.MyModel]"
+        reveal_type(MyModel.objects.queryset_method(1))  # N: Revealed type is "Any"
+        reveal_type(MyModel.objects.queryset_method)  # N: Revealed type is "def (qarg: Any) -> Any"
+        reveal_type(MyModel.objects.manager_method(2))  # N: Revealed type is "Any"
+        reveal_type(MyModel.objects.manager_method)  # N: Revealed type is "def (marg: Any) -> Any"
+    installed_apps:
+        - myapp
+    files:
+        -   path: myapp/__init__.py
+        -   path: myapp/models.py
+            content: |
+                from django.db import models
+                from typing import Any
+
+                class ModelQuerySet(models.QuerySet):
+                    def queryset_method(self, qarg: Any) -> Any:
+                        return 'hello'
+
+                class MyManager(models.Manager):
+                    def manager_method(self, marg: Any) -> Any:
+                        return 'hello'
+
+                NewManager = MyManager.from_queryset(ModelQuerySet)
+                class MyModel(models.Model):
+                    objects = NewManager()