Commit af4a8478 authored by Andrew Godwin's avatar Andrew Godwin
Browse files

Fixed #21783: (again) Found second source of bug, also squashed it.

parent e8d4aed3

django/db/migrations/operations/fields.py

+9 −1
Original line number Diff line number Diff line
@@ -27,7 +27,15 @@ class AddField(Operation): 
        from_model = from_state.render().get_model(app_label, self.model_name)

        to_model = to_state.render().get_model(app_label, self.model_name)

        if router.allow_migrate(schema_editor.connection.alias, to_model):

            schema_editor.add_field(from_model, to_model._meta.get_field_by_name(self.name)[0])

            field = to_model._meta.get_field_by_name(self.name)[0]

            if not self.preserve_default:

                field.default = self.field.default

            schema_editor.add_field(

                from_model,

                field,

            )

            if not self.preserve_default:

                field.default = NOT_PROVIDED



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

        from_model = from_state.render().get_model(app_label, self.model_name)

tests/migrations/test_operations.py

+8 −0
Original line number Diff line number Diff line
@@ -184,6 +184,14 @@ class OperationTests(MigrationTestBase): 
            if n == "height"

        ][0]

        self.assertEqual(field.default, NOT_PROVIDED)

        # Test the database alteration

        project_state.render().get_model("test_adflpd", "pony").objects.create(

            weight = 4,

        )

        self.assertColumnNotExists("test_adflpd_pony", "height")

        with connection.schema_editor() as editor:

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

        self.assertColumnExists("test_adflpd_pony", "height")



    def test_add_field_m2m(self):

        """