Commit 28db4af8 authored by Tim Graham's avatar Tim Graham
Browse files

Fixed #24135 -- Made RenameModel rename many-to-many tables. 

Thanks Simon and Markus for reviews.
parent 3f9ec12d

django/db/migrations/operations/models.py

+21 −0
Original line number Diff line number Diff line
@@ -216,6 +216,27 @@ class RenameModel(Operation): 
                    related_object.field,

                    to_field,

                )

            # Rename M2M fields whose name is based on this model's name.

            fields = zip(old_model._meta.local_many_to_many, new_model._meta.local_many_to_many)

            for (old_field, new_field) in fields:

                # Skip self-referential fields as these are renamed above.

                if new_field.model == new_field.related_model or not new_field.rel.through._meta.auto_created:

                    continue

                # Rename the M2M table that's based on this model's name.

                old_m2m_model = old_field.rel.through

                new_m2m_model = new_field.rel.through

                schema_editor.alter_db_table(

                    new_m2m_model,

                    old_m2m_model._meta.db_table,

                    new_m2m_model._meta.db_table,

                )

                # Rename the column in the M2M table that's based on this

                # model's name.

                schema_editor.alter_field(

                    new_m2m_model,

                    old_m2m_model._meta.get_field(old_model._meta.model_name),

                    new_m2m_model._meta.get_field(new_model._meta.model_name),

                )



    def database_backwards(self, app_label, schema_editor, from_state, to_state):

        self.new_name_lower, self.old_name_lower = self.old_name_lower, self.new_name_lower

docs/releases/1.7.4.txt

+3 −0
Original line number Diff line number Diff line
@@ -11,3 +11,6 @@ Bugfixes 


* Fixed a migration crash when unapplying ``contrib.contenttypes``’s or

  ``contrib.auth``’s first migration (:ticket:`24075`).



* Made the migration's ``RenameModel`` operation rename ``ManyToManyField``

  tables (:ticket:`24135`).

tests/migrations/test_operations.py

+26 −0
Original line number Diff line number Diff line
@@ -553,6 +553,32 @@ class OperationTests(OperationTestBase): 
        pony = Pony.objects.create()

        pony.ponies.add(pony)



    def test_rename_model_with_m2m(self):

        app_label = "test_rename_model_with_m2m"

        project_state = self.apply_operations(app_label, ProjectState(), operations=[

            migrations.CreateModel("Rider", fields=[]),

            migrations.CreateModel("Pony", fields=[

                ("riders", models.ManyToManyField("Rider")),

            ]),

        ])

        Pony = project_state.apps.get_model(app_label, "Pony")

        Rider = project_state.apps.get_model(app_label, "Rider")

        pony = Pony.objects.create()

        rider = Rider.objects.create()

        pony.riders.add(rider)



        project_state = self.apply_operations(app_label, project_state, operations=[

            migrations.RenameModel("Pony", "Pony2"),

        ])

        Pony = project_state.apps.get_model(app_label, "Pony2")

        Rider = project_state.apps.get_model(app_label, "Rider")

        pony = Pony.objects.create()

        rider = Rider.objects.create()

        pony.riders.add(rider)

        self.assertEqual(Pony.objects.count(), 2)

        self.assertEqual(Rider.objects.count(), 2)

        self.assertEqual(Pony._meta.get_field('riders').rel.through.objects.count(), 2)



    def test_add_field(self):

        """

        Tests the AddField operation.