Fixed #24812 -- Fixed app registry RuntimeWarnings in schema and migrations tests.

tests/migrations/test_state.py

@@ -396,17 +396,22 @@ class StateTests(TestCase):
         #24573 - Adding relations to existing models should reload the
         referenced models too.
         """
+        new_apps = Apps()
+
         class A(models.Model):
             class Meta:
                 app_label = 'something'
+                apps = new_apps
 
         class B(A):
             class Meta:
                 app_label = 'something'
+                apps = new_apps
 
         class C(models.Model):
             class Meta:
                 app_label = 'something'
+                apps = new_apps
 
         project_state = ProjectState()
         project_state.add_model(ModelState.from_model(A))
@@ -447,15 +452,19 @@ class StateTests(TestCase):
         #24225 - Tests that relations between models are updated while
         remaining the relations and references for models of an old state.
         """
+        new_apps = Apps()
+
         class A(models.Model):
             class Meta:
                 app_label = "something"
+                apps = new_apps
 
         class B(models.Model):
             to_a = models.ForeignKey(A)
 
             class Meta:
                 app_label = "something"
+                apps = new_apps
 
         def get_model_a(state):
             return [mod for mod in state.apps.get_models() if mod._meta.model_name == 'a'][0]

tests/schema/tests.py

@@ -765,8 +765,10 @@ class SchemaTests(TransactionTestCase):
                 app_label = 'schema'
                 apps = new_apps
 
-        self.local_models = [LocalBookWithM2M]
-
+        self.local_models = [
+            LocalBookWithM2M,
+            LocalBookWithM2M._meta.get_field('tags').remote_field.through,
+        ]
         # Create the tables
         with connection.schema_editor() as editor:
             editor.create_model(Author)
@@ -845,6 +847,7 @@ class SchemaTests(TransactionTestCase):
         # Create an M2M field
         new_field = M2MFieldClass("schema.TagM2MTest", related_name="authors")
         new_field.contribute_to_class(LocalAuthorWithM2M, "tags")
+        self.local_models += [new_field.remote_field.through]
         # Ensure there's no m2m table there
         self.assertRaises(DatabaseError, self.column_classes, new_field.remote_field.through)
         # Add the field
@@ -934,7 +937,10 @@ class SchemaTests(TransactionTestCase):
                 app_label = 'schema'
                 apps = new_apps
 
-        self.local_models = [LocalBookWithM2M]
+        self.local_models = [
+            LocalBookWithM2M,
+            LocalBookWithM2M._meta.get_field('tags').remote_field.through,
+        ]
 
         # Create the tables
         with connection.schema_editor() as editor:
@@ -955,6 +961,7 @@ class SchemaTests(TransactionTestCase):
         old_field = LocalBookWithM2M._meta.get_field("tags")
         new_field = M2MFieldClass(UniqueTest)
         new_field.contribute_to_class(LocalBookWithM2M, "uniques")
+        self.local_models += [new_field.remote_field.through]
         with connection.schema_editor() as editor:
             editor.alter_field(LocalBookWithM2M, old_field, new_field)
         # Ensure old M2M is gone