Commit dab83e5b authored by Loïc Bistuer's avatar Loïc Bistuer
Browse files

Fixed #26881 -- Fixed duplicate managers in migrations. 

When both parent and child models had managers with the same name and
a migrations opt-in both were added to the migration state.
parent ba53da89

django/db/migrations/state.py

+10 −2
Original line number Diff line number Diff line
@@ -447,12 +447,19 @@ class ModelState(object): 
            bases = (models.Model,)



        managers = []

        manager_names = set()

        default_manager_shim = None

        for manager in model._meta.managers:

            if manager.use_in_migrations:

            manager_name = force_text(manager.name)

            if manager_name in manager_names:

                # Skip overridden managers.

                continue

            elif manager.use_in_migrations:

                # Copy managers usable in migrations.

                new_manager = copy.copy(manager)

                new_manager._set_creation_counter()

            elif manager is model._base_manager or manager is model._default_manager:

                # Shim custom managers used as default and base managers.

                new_manager = models.Manager()

                new_manager.model = manager.model

                new_manager.name = manager.name
@@ -460,7 +467,8 @@ class ModelState(object): 
                    default_manager_shim = new_manager

            else:

                continue

            managers.append((force_text(manager.name), new_manager))

            manager_names.add(manager_name)

            managers.append((manager_name, new_manager))



        # Ignore a shimmed default manager called objects if it's the only one.

        if managers == [('objects', default_manager_shim)]:

tests/migrations/test_state.py

+31 −0
Original line number Diff line number Diff line
@@ -210,6 +210,37 @@ class StateTests(SimpleTestCase): 
        author_state = project_state.models['migrations', 'author']

        self.assertEqual(author_state.managers, [])



    def test_no_duplicate_managers(self):

        """

        When a manager is added with `use_in_migrations = True` and a parent

        model had a manager with the same name and `use_in_migrations = True`,

        the parent's manager shouldn't appear in the model state (#26881).

        """

        new_apps = Apps(['migrations'])



        class PersonManager(models.Manager):

            use_in_migrations = True



        class Person(models.Model):

            objects = PersonManager()



            class Meta:

                abstract = True



        class BossManager(PersonManager):

            use_in_migrations = True



        class Boss(Person):

            objects = BossManager()



            class Meta:

                app_label = 'migrations'

                apps = new_apps



        project_state = ProjectState.from_apps(new_apps)

        boss_state = project_state.models['migrations', 'boss']

        self.assertEqual(boss_state.managers, [('objects', Boss.objects)])



    def test_custom_default_manager(self):

        new_apps = Apps(['migrations'])