[1.7.x] Fixed #23160 -- Correctly rename models with self referential fields. (6b2473d3) · Commits · Dom Sekotill / django

django/db/migrations/operations/models.py

+19 −7

Original line number	Diff line number	Diff line
		@@ -124,6 +124,10 @@ class RenameModel(Operation):
		del state.models[app_label, self.old_name.lower()]
		# Repoint the FKs and M2Ms pointing to us
		for related_object in (related_objects + related_m2m_objects):
		# Use the new related key for self referential related objects.
		if related_object.model == model:
		related_key = (app_label, self.new_name.lower())
		else:
		related_key = (
		related_object.model._meta.app_label,
		related_object.model._meta.object_name.lower(),
		@@ -152,12 +156,20 @@ class RenameModel(Operation):
		related_objects = old_model._meta.get_all_related_objects()
		related_m2m_objects = old_model._meta.get_all_related_many_to_many_objects()
		for related_object in (related_objects + related_m2m_objects):
		to_field = new_apps.get_model(
		if related_object.model == old_model:
		model = new_model
		related_key = (app_label, self.new_name.lower())
		else:
		model = related_object.model
		related_key = (
		related_object.model._meta.app_label,
		related_object.model._meta.object_name.lower(),
		)
		to_field = new_apps.get_model(
		*related_key
		)._meta.get_field_by_name(related_object.field.name)[0]
		schema_editor.alter_field(
		related_object.model,
		model,
		related_object.field,
		to_field,
		)

tests/migrations/test_operations.py

+37 −0

Original line number	Diff line number	Diff line
		@@ -111,6 +111,7 @@ class OperationTestBase(MigrationTestBase):
		[
		("id", models.AutoField(primary_key=True)),
		("pony", models.ForeignKey("Pony")),
		("friend", models.ForeignKey("self"))
		],
		))
		if mti_model:
		@@ -406,6 +407,42 @@ class OperationTests(OperationTestBase):
		self.assertFKExists("test_rnmo_rider", ["pony_id"], ("test_rnmo_pony", "id"))
		self.assertFKNotExists("test_rnmo_rider", ["pony_id"], ("test_rnmo_horse", "id"))

		def test_rename_model_with_self_referential_fk(self):
		"""
		Tests the RenameModel operation on model with self referential FK.
		"""
		project_state = self.set_up_test_model("test_rmwsrf", related_model=True)
		# Test the state alteration
		operation = migrations.RenameModel("Rider", "HorseRider")
		self.assertEqual(operation.describe(), "Rename model Rider to HorseRider")
		new_state = project_state.clone()
		operation.state_forwards("test_rmwsrf", new_state)
		self.assertNotIn(("test_rmwsrf", "rider"), new_state.models)
		self.assertIn(("test_rmwsrf", "horserider"), new_state.models)
		# Remember, RenameModel also repoints all incoming FKs and M2Ms
		self.assertEqual("test_rmwsrf.HorseRider", new_state.models["test_rmwsrf", "horserider"].fields[2][1].rel.to)
		# Test the database alteration
		self.assertTableExists("test_rmwsrf_rider")
		self.assertTableNotExists("test_rmwsrf_horserider")
		if connection.features.supports_foreign_keys:
		self.assertFKExists("test_rmwsrf_rider", ["friend_id"], ("test_rmwsrf_rider", "id"))
		self.assertFKNotExists("test_rmwsrf_horserider", ["friend_id"], ("test_rmwsrf_horserider", "id"))
		with connection.schema_editor() as editor:
		operation.database_forwards("test_rmwsrf", editor, project_state, new_state)
		self.assertTableNotExists("test_rmwsrf_rider")
		self.assertTableExists("test_rmwsrf_horserider")
		if connection.features.supports_foreign_keys:
		self.assertFKNotExists("test_rmwsrf_rider", ["friend_id"], ("test_rmwsrf_rider", "id"))
		self.assertFKExists("test_rmwsrf_horserider", ["friend_id"], ("test_rmwsrf_horserider", "id"))
		# And test reversal
		with connection.schema_editor() as editor:
		operation.database_backwards("test_rmwsrf", editor, new_state, project_state)
		self.assertTableExists("test_rmwsrf_rider")
		self.assertTableNotExists("test_rmwsrf_horserider")
		if connection.features.supports_foreign_keys:
		self.assertFKExists("test_rmwsrf_rider", ["friend_id"], ("test_rmwsrf_rider", "id"))
		self.assertFKNotExists("test_rmwsrf_horserider", ["friend_id"], ("test_rmwsrf_horserider", "id"))

		def test_add_field(self):
		"""
		Tests the AddField operation.