add PlaceholderNode when deferring manager class hook (typeddjango#2228) (#19)

Co-authored-by: Anthony Sottile <[email protected]>

Author: asottile-sentry

mypy_django_plugin/transformers/managers.py

@@ -10,6 +10,7 @@
     MemberExpr,
     Node,
     OverloadedFuncDef,
+    PlaceholderNode,
     RefExpr,
     StrExpr,
     SymbolTableNode,
@@ -314,6 +315,9 @@ def create_new_manager_class_from_from_queryset_method(ctx: DynamicClassDefConte
     new_manager_info = create_manager_info_from_from_queryset_call(semanal_api, ctx.call, ctx.name)
     if new_manager_info is None:
         if not ctx.api.final_iteration:
+            # XXX: hack for python/mypy#17402
+            ph = PlaceholderNode(ctx.api.qualified_name(ctx.name), ctx.call, ctx.call.line, becomes_typeinfo=True)
+            ctx.api.add_symbol_table_node(ctx.name, SymbolTableNode(GDEF, ph))
             ctx.api.defer()
         return
 

tests/typecheck/managers/querysets/test_from_queryset.yml

@@ -822,6 +822,41 @@
                     self.ttl = ttl
                     super().__init__(*a, **k)
 
+-   case: test_from_queryset_with_deferral
+    main: |
+        from myapp.models import Concrete
+        reveal_type(Concrete.objects.qs_meth())  # N: Revealed type is "builtins.int"
+        reveal_type(Concrete.objects.manager_meth())  # N: Revealed type is "builtins.str"
+    mypy_config: |
+        [mypy.plugins.django-stubs]
+        django_settings_module = myapp
+    files:
+        -   path: myapp/__init__.py
+        -   path: myapp/models.py
+            content: |
+                from typing import TypeVar, ClassVar
+                from typing_extensions import Self
+                from django.db import models
+                from django.db.models.manager import Manager
+
+                M = TypeVar("M", bound=models.Model, covariant=True)
+
+                # bogus forward-`metaclass=` to trigger second semanal pass similar to #2224
+                class CustomQuerySet(models.QuerySet[M], metaclass=MCS):
+                    def qs_meth(self) -> int:
+                        return 1
+
+                _base = Manager.from_queryset(CustomQuerySet)
+
+                class CustomBase(_base[M]):
+                    def manager_meth(self) -> str:
+                        return 'hi'
+
+                class Concrete(models.Model):
+                    objects: ClassVar[CustomBase[Self]] = CustomBase()
+
+                class MCS(type): pass
+
 -   case: test_queryset_arg_as_unsupported_expressions
     main: |
         from typing import Union, Generic, TypeVar