Commit 22a67d22 authored by Matthew Wilkes's avatar Matthew Wilkes Committed by Tim Graham
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[1.8.x] Refs #24354 -- Prevented repointing of relations on superclasses when... 

[1.8.x] Refs #24354 -- Prevented repointing of relations on superclasses when migrating a subclass's name change

Forwardport of test and release note from stable/1.7.x

Backport of ae87ad00 from master
parent da8b3aa7

docs/releases/1.7.7.txt

+3 −1
Original line number Diff line number Diff line
@@ -9,4 +9,6 @@ Django 1.7.7 fixes several bugs in 1.7.6. 
Bugfixes

========



* ...
 
* Fixed renaming of classes in migrations where renaming a subclass would

  cause incorrect state to be recorded for objects that referenced the

  superclass (:ticket:`24354`).

tests/migrations/test_operations.py

+35 −0
Original line number Diff line number Diff line
@@ -538,6 +538,41 @@ class OperationTests(OperationTestBase): 
            self.assertFKExists("test_rmwsrf_rider", ["friend_id"], ("test_rmwsrf_rider", "id"))

            self.assertFKNotExists("test_rmwsrf_rider", ["friend_id"], ("test_rmwsrf_horserider", "id"))



    def test_rename_model_with_superclass_fk(self):

        """

        Tests the RenameModel operation on a model which has a superclass that

        has a foreign key.

        """

        project_state = self.set_up_test_model("test_rmwsc", related_model=True, mti_model=True)

        # Test the state alteration

        operation = migrations.RenameModel("ShetlandPony", "LittleHorse")

        self.assertEqual(operation.describe(), "Rename model ShetlandPony to LittleHorse")

        new_state = project_state.clone()

        operation.state_forwards("test_rmwsc", new_state)

        self.assertNotIn(("test_rmwsc", "shetlandpony"), new_state.models)

        self.assertIn(("test_rmwsc", "littlehorse"), new_state.models)

        # RenameModel shouldn't repoint the superclass's relations, only local ones

        self.assertEqual(

            project_state.models["test_rmwsc", "rider"].fields[1][1].rel.to,

            new_state.models["test_rmwsc", "rider"].fields[1][1].rel.to

        )

        # Before running the migration we have a table for Shetland Pony, not Little Horse

        self.assertTableExists("test_rmwsc_shetlandpony")

        self.assertTableNotExists("test_rmwsc_littlehorse")

        if connection.features.supports_foreign_keys:

            # and the foreign key on rider points to pony, not shetland pony

            self.assertFKExists("test_rmwsc_rider", ["pony_id"], ("test_rmwsc_pony", "id"))

            self.assertFKNotExists("test_rmwsc_rider", ["pony_id"], ("test_rmwsc_shetlandpony", "id"))

        with connection.schema_editor() as editor:

            operation.database_forwards("test_rmwsc", editor, project_state, new_state)

        # Now we have a little horse table, not shetland pony

        self.assertTableNotExists("test_rmwsc_shetlandpony")

        self.assertTableExists("test_rmwsc_littlehorse")

        if connection.features.supports_foreign_keys:

            # but the Foreign keys still point at pony, not little horse

            self.assertFKExists("test_rmwsc_rider", ["pony_id"], ("test_rmwsc_pony", "id"))

            self.assertFKNotExists("test_rmwsc_rider", ["pony_id"], ("test_rmwsc_littlehorse", "id"))



    def test_rename_model_with_self_referential_m2m(self):

        app_label = "test_rename_model_with_self_referential_m2m"