Python django.db.migrations.DeleteModel() Examples

def test_remove_field_m2m_with_through(self):
        project_state = self.set_up_test_model("test_rmflmmwt", second_model=True)

        self.assertTableNotExists("test_rmflmmwt_ponystables")
        project_state = self.apply_operations("test_rmflmmwt", project_state, operations=[
            migrations.CreateModel("PonyStables", fields=[
                ("pony", models.ForeignKey('test_rmflmmwt.Pony', models.CASCADE)),
                ("stable", models.ForeignKey('test_rmflmmwt.Stable', models.CASCADE)),
            ]),
            migrations.AddField(
                "Pony", "stables",
                models.ManyToManyField("Stable", related_name="ponies", through='test_rmflmmwt.PonyStables')
            )
        ])
        self.assertTableExists("test_rmflmmwt_ponystables")

        operations = [migrations.RemoveField("Pony", "stables"), migrations.DeleteModel("PonyStables")]
        self.apply_operations("test_rmflmmwt", project_state, operations=operations) 

def test_delete_model(self):
        """
        Tests the DeleteModel operation.
        """
        project_state = self.set_up_test_model("test_dlmo")
        # Test the state alteration
        operation = migrations.DeleteModel("Pony")
        self.assertEqual(operation.describe(), "Delete model Pony")
        new_state = project_state.clone()
        operation.state_forwards("test_dlmo", new_state)
        self.assertNotIn(("test_dlmo", "pony"), new_state.models)
        # Test the database alteration
        self.assertTableExists("test_dlmo_pony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dlmo", editor, project_state, new_state)
        self.assertTableNotExists("test_dlmo_pony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dlmo", editor, new_state, project_state)
        self.assertTableExists("test_dlmo_pony")
        # And deconstruction
        definition = operation.deconstruct()
        self.assertEqual(definition[0], "DeleteModel")
        self.assertEqual(definition[1], [])
        self.assertEqual(list(definition[2]), ["name"]) 

def test_optimize_elidable_operation(self):
        elidable_operation = operations.base.Operation()
        elidable_operation.elidable = True
        self.assertOptimizesTo(
            [
                elidable_operation,
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                elidable_operation,
                migrations.CreateModel("Bar", [("size", models.IntegerField())]),
                elidable_operation,
                migrations.RenameModel("Foo", "Phou"),
                migrations.DeleteModel("Bar"),
                elidable_operation,
            ],
            [
                migrations.CreateModel("Phou", [("name", models.CharField(max_length=255))]),
            ],
        ) 

def test_optimize_through_fields(self):
        """
        field-level through checking is working. This should manage to collapse
        model Foo to nonexistence, and model Bar to a single IntegerField
        called "width".
        """
        self.assertOptimizesTo(
            [
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                migrations.CreateModel("Bar", [("size", models.IntegerField())]),
                migrations.AddField("Foo", "age", models.IntegerField()),
                migrations.AddField("Bar", "width", models.IntegerField()),
                migrations.AlterField("Foo", "age", models.IntegerField()),
                migrations.RenameField("Bar", "size", "dimensions"),
                migrations.RemoveField("Foo", "age"),
                migrations.RenameModel("Foo", "Phou"),
                migrations.RemoveField("Bar", "dimensions"),
                migrations.RenameModel("Phou", "Fou"),
                migrations.DeleteModel("Fou"),
            ],
            [
                migrations.CreateModel("Bar", [("width", models.IntegerField())]),
            ],
        ) 

def test_optimize_through_fields(self):
        """
        field-level through checking is working. This should manage to collapse
        model Foo to nonexistence, and model Bar to a single IntegerField
        called "width".
        """
        self.assertOptimizesTo(
            [
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                migrations.CreateModel("Bar", [("size", models.IntegerField())]),
                migrations.AddField("Foo", "age", models.IntegerField()),
                migrations.AddField("Bar", "width", models.IntegerField()),
                migrations.AlterField("Foo", "age", models.IntegerField()),
                migrations.RenameField("Bar", "size", "dimensions"),
                migrations.RemoveField("Foo", "age"),
                migrations.RenameModel("Foo", "Phou"),
                migrations.RemoveField("Bar", "dimensions"),
                migrations.RenameModel("Phou", "Fou"),
                migrations.DeleteModel("Fou"),
            ],
            [
                migrations.CreateModel("Bar", [("width", models.IntegerField())]),
            ],
        ) 

def test_optimize_elidable_operation(self):
        elidable_operation = operations.base.Operation()
        elidable_operation.elidable = True
        self.assertOptimizesTo(
            [
                elidable_operation,
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                elidable_operation,
                migrations.CreateModel("Bar", [("size", models.IntegerField())]),
                elidable_operation,
                migrations.RenameModel("Foo", "Phou"),
                migrations.DeleteModel("Bar"),
                elidable_operation,
            ],
            [
                migrations.CreateModel("Phou", [("name", models.CharField(max_length=255))]),
            ],
        ) 

def test_delete_proxy_model(self):
        """
        Tests the DeleteModel operation ignores proxy models.
        """
        project_state = self.set_up_test_model("test_dlprmo", proxy_model=True)
        # Test the state alteration
        operation = migrations.DeleteModel("ProxyPony")
        new_state = project_state.clone()
        operation.state_forwards("test_dlprmo", new_state)
        self.assertIn(("test_dlprmo", "proxypony"), project_state.models)
        self.assertNotIn(("test_dlprmo", "proxypony"), new_state.models)
        # Test the database alteration
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dlprmo", editor, project_state, new_state)
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dlprmo", editor, new_state, project_state)
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony") 

def test_delete_proxy_model(self):
        """
        Tests the DeleteModel operation ignores proxy models.
        """
        project_state = self.set_up_test_model("test_dlprmo", proxy_model=True)
        # Test the state alteration
        operation = migrations.DeleteModel("ProxyPony")
        new_state = project_state.clone()
        operation.state_forwards("test_dlprmo", new_state)
        self.assertIn(("test_dlprmo", "proxypony"), project_state.models)
        self.assertNotIn(("test_dlprmo", "proxypony"), new_state.models)
        # Test the database alteration
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dlprmo", editor, project_state, new_state)
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dlprmo", editor, new_state, project_state)
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony") 

def test_delete_mti_model(self):
        project_state = self.set_up_test_model('test_dlmtimo', mti_model=True)
        # Test the state alteration
        operation = migrations.DeleteModel('ShetlandPony')
        new_state = project_state.clone()
        operation.state_forwards('test_dlmtimo', new_state)
        self.assertIn(('test_dlmtimo', 'shetlandpony'), project_state.models)
        self.assertNotIn(('test_dlmtimo', 'shetlandpony'), new_state.models)
        # Test the database alteration
        self.assertTableExists('test_dlmtimo_pony')
        self.assertTableExists('test_dlmtimo_shetlandpony')
        self.assertColumnExists('test_dlmtimo_shetlandpony', 'pony_ptr_id')
        with connection.schema_editor() as editor:
            operation.database_forwards('test_dlmtimo', editor, project_state, new_state)
        self.assertTableExists('test_dlmtimo_pony')
        self.assertTableNotExists('test_dlmtimo_shetlandpony')
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards('test_dlmtimo', editor, new_state, project_state)
        self.assertTableExists('test_dlmtimo_pony')
        self.assertTableExists('test_dlmtimo_shetlandpony')
        self.assertColumnExists('test_dlmtimo_shetlandpony', 'pony_ptr_id') 

def test_delete_proxy_model(self):
        """
        Tests the DeleteModel operation ignores proxy models.
        """
        project_state = self.set_up_test_model("test_dlprmo", proxy_model=True)
        # Test the state alteration
        operation = migrations.DeleteModel("ProxyPony")
        new_state = project_state.clone()
        operation.state_forwards("test_dlprmo", new_state)
        self.assertIn(("test_dlprmo", "proxypony"), project_state.models)
        self.assertNotIn(("test_dlprmo", "proxypony"), new_state.models)
        # Test the database alteration
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dlprmo", editor, project_state, new_state)
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dlprmo", editor, new_state, project_state)
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony") 

def test_delete_model(self):
        """
        Tests the DeleteModel operation.
        """
        project_state = self.set_up_test_model("test_dlmo")
        # Test the state alteration
        operation = migrations.DeleteModel("Pony")
        self.assertEqual(operation.describe(), "Delete model Pony")
        new_state = project_state.clone()
        operation.state_forwards("test_dlmo", new_state)
        self.assertNotIn(("test_dlmo", "pony"), new_state.models)
        # Test the database alteration
        self.assertTableExists("test_dlmo_pony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dlmo", editor, project_state, new_state)
        self.assertTableNotExists("test_dlmo_pony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dlmo", editor, new_state, project_state)
        self.assertTableExists("test_dlmo_pony")
        # And deconstruction
        definition = operation.deconstruct()
        self.assertEqual(definition[0], "DeleteModel")
        self.assertEqual(definition[1], [])
        self.assertEqual(list(definition[2]), ["name"]) 

def test_optimize_elidable_operation(self):
        elidable_operation = operations.base.Operation()
        elidable_operation.elidable = True
        self.assertOptimizesTo(
            [
                elidable_operation,
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                elidable_operation,
                migrations.CreateModel("Bar", [("size", models.IntegerField())]),
                elidable_operation,
                migrations.RenameModel("Foo", "Phou"),
                migrations.DeleteModel("Bar"),
                elidable_operation,
            ],
            [
                migrations.CreateModel("Phou", [("name", models.CharField(max_length=255))]),
            ],
        ) 

def test_optimize_through_fields(self):
        """
        field-level through checking is working. This should manage to collapse
        model Foo to nonexistence, and model Bar to a single IntegerField
        called "width".
        """
        self.assertOptimizesTo(
            [
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                migrations.CreateModel("Bar", [("size", models.IntegerField())]),
                migrations.AddField("Foo", "age", models.IntegerField()),
                migrations.AddField("Bar", "width", models.IntegerField()),
                migrations.AlterField("Foo", "age", models.IntegerField()),
                migrations.RenameField("Bar", "size", "dimensions"),
                migrations.RemoveField("Foo", "age"),
                migrations.RenameModel("Foo", "Phou"),
                migrations.RemoveField("Bar", "dimensions"),
                migrations.RenameModel("Phou", "Fou"),
                migrations.DeleteModel("Fou"),
            ],
            [
                migrations.CreateModel("Bar", [("width", models.IntegerField())]),
            ],
        ) 

def test_remove_field_m2m_with_through(self):
        project_state = self.set_up_test_model("test_rmflmmwt", second_model=True)

        self.assertTableNotExists("test_rmflmmwt_ponystables")
        project_state = self.apply_operations("test_rmflmmwt", project_state, operations=[
            migrations.CreateModel("PonyStables", fields=[
                ("pony", models.ForeignKey('test_rmflmmwt.Pony', models.CASCADE)),
                ("stable", models.ForeignKey('test_rmflmmwt.Stable', models.CASCADE)),
            ]),
            migrations.AddField(
                "Pony", "stables",
                models.ManyToManyField("Stable", related_name="ponies", through='test_rmflmmwt.PonyStables')
            )
        ])
        self.assertTableExists("test_rmflmmwt_ponystables")

        operations = [migrations.RemoveField("Pony", "stables"), migrations.DeleteModel("PonyStables")]
        self.apply_operations("test_rmflmmwt", project_state, operations=operations) 

def test_remove_field_m2m_with_through(self):
        project_state = self.set_up_test_model("test_rmflmmwt", second_model=True)

        self.assertTableNotExists("test_rmflmmwt_ponystables")
        project_state = self.apply_operations("test_rmflmmwt", project_state, operations=[
            migrations.CreateModel("PonyStables", fields=[
                ("pony", models.ForeignKey('test_rmflmmwt.Pony', models.CASCADE)),
                ("stable", models.ForeignKey('test_rmflmmwt.Stable', models.CASCADE)),
            ]),
            migrations.AddField(
                "Pony", "stables",
                models.ManyToManyField("Stable", related_name="ponies", through='test_rmflmmwt.PonyStables')
            )
        ])
        self.assertTableExists("test_rmflmmwt_ponystables")

        operations = [migrations.RemoveField("Pony", "stables"), migrations.DeleteModel("PonyStables")]
        self.apply_operations("test_rmflmmwt", project_state, operations=operations) 

def test_create_delete_model(self):
        """
        CreateModel and DeleteModel should collapse into nothing.
        """
        self.assertOptimizesTo(
            [
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                migrations.DeleteModel("Foo"),
            ],
            [],
        ) 

def _test_create_alter_foo_delete_model(self, alter_foo):
        """
        CreateModel, AlterModelTable, AlterUniqueTogether/AlterIndexTogether/
        AlterOrderWithRespectTo, and DeleteModel should collapse into nothing.
        """
        self.assertOptimizesTo(
            [
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                migrations.AlterModelTable("Foo", "woohoo"),
                alter_foo,
                migrations.DeleteModel("Foo"),
            ],
            [],
        ) 

def create_drop_model(field, filters: List[str]):
    """Creates and drops a model with the specified field.

    Arguments:
        field:
            The field to include on the
            model to create and drop.

        filters:
            List of strings to filter
            SQL statements on.
    """

    model = define_fake_model({"title": field})

    with filtered_schema_editor(*filters) as calls:
        apply_migration(
            [
                migrations.CreateModel(
                    model.__name__, fields=[("title", field.clone())]
                ),
                migrations.DeleteModel(model.__name__),
            ]
        )

    yield calls 

def test_simple_migration(self):
        """
        Tests serializing a simple migration.
        """
        fields = {
            'charfield': models.DateTimeField(default=datetime.datetime.utcnow),
            'datetimefield': models.DateTimeField(default=datetime.datetime.utcnow),
        }

        options = {
            'verbose_name': 'My model',
            'verbose_name_plural': 'My models',
        }

        migration = type("Migration", (migrations.Migration,), {
            "operations": [
                migrations.CreateModel("MyModel", tuple(fields.items()), options, (models.Model,)),
                migrations.CreateModel("MyModel2", tuple(fields.items()), bases=(models.Model,)),
                migrations.CreateModel(
                    name="MyModel3", fields=tuple(fields.items()), options=options, bases=(models.Model,)
                ),
                migrations.DeleteModel("MyModel"),
                migrations.AddField("OtherModel", "datetimefield", fields["datetimefield"]),
            ],
            "dependencies": [("testapp", "some_other_one")],
        })
        writer = MigrationWriter(migration)
        output = writer.as_string()
        # We don't test the output formatting - that's too fragile.
        # Just make sure it runs for now, and that things look alright.
        result = self.safe_exec(output)
        self.assertIn("Migration", result) 

def test_delete_ignore_swapped(self):
        """
        Tests the DeleteModel operation ignores swapped models.
        """
        operation = migrations.DeleteModel("Pony")
        project_state, new_state = self.make_test_state("test_dligsw", operation)
        # Test the database alteration
        self.assertTableNotExists("test_dligsw_pony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dligsw", editor, project_state, new_state)
        self.assertTableNotExists("test_dligsw_pony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dligsw", editor, new_state, project_state)
        self.assertTableNotExists("test_dligsw_pony") 

def tearDown(self):
        # Delete table after testing
        if hasattr(self, 'current_state'):
            self.apply_operations('gis', self.current_state, [migrations.DeleteModel('Neighborhood')])
        super().tearDown() 

def reduce_model_create_delete(self, operation, other, in_between):
        """
        Folds a CreateModel and a DeleteModel into nothing.
        """
        if (operation.name_lower == other.name_lower and
                not operation.options.get("proxy", False)):
            return [] 

def tearDown(self):
        # Delete table after testing
        if hasattr(self, 'current_state'):
            self.apply_operations('gis', self.current_state, [migrations.DeleteModel('Neighborhood')])
        super().tearDown() 

def test_delete_ignore_swapped(self):
        """
        Tests the DeleteModel operation ignores swapped models.
        """
        operation = migrations.DeleteModel("Pony")
        project_state, new_state = self.make_test_state("test_dligsw", operation)
        # Test the database alteration
        self.assertTableNotExists("test_dligsw_pony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dligsw", editor, project_state, new_state)
        self.assertTableNotExists("test_dligsw_pony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dligsw", editor, new_state, project_state)
        self.assertTableNotExists("test_dligsw_pony") 

def _test_create_alter_foo_delete_model(self, alter_foo):
        """
        CreateModel, AlterModelTable, AlterUniqueTogether/AlterIndexTogether/
        AlterOrderWithRespectTo, and DeleteModel should collapse into nothing.
        """
        self.assertOptimizesTo(
            [
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                migrations.AlterModelTable("Foo", "woohoo"),
                alter_foo,
                migrations.DeleteModel("Foo"),
            ],
            [],
        ) 

def test_create_delete_model(self):
        """
        CreateModel and DeleteModel should collapse into nothing.
        """
        self.assertOptimizesTo(
            [
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                migrations.DeleteModel("Foo"),
            ],
            [],
        ) 

def test_single(self):
        """
        The optimizer does nothing on a single operation,
        and that it does it in just one pass.
        """
        self.assertOptimizesTo(
            [migrations.DeleteModel("Foo")],
            [migrations.DeleteModel("Foo")],
            exact=1,
        ) 

def dropHistoricalTable(apps, schema_editor):
    """
    Drops the historical sap_success_factors table named herein.
    """
    table_name = 'sap_success_factors_historicalsapsuccessfactorsenterprisecus80ad'
    if table_name in connection.introspection.table_names():
        migrations.DeleteModel(
            name=table_name,
        ) 

def test_delete_ignore_swapped(self):
        """
        Tests the DeleteModel operation ignores swapped models.
        """
        operation = migrations.DeleteModel("Pony")
        project_state, new_state = self.make_test_state("test_dligsw", operation)
        # Test the database alteration
        self.assertTableNotExists("test_dligsw_pony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dligsw", editor, project_state, new_state)
        self.assertTableNotExists("test_dligsw_pony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dligsw", editor, new_state, project_state)
        self.assertTableNotExists("test_dligsw_pony") 

def _test_create_alter_foo_delete_model(self, alter_foo):
        """
        CreateModel, AlterModelTable, AlterUniqueTogether/AlterIndexTogether/
        AlterOrderWithRespectTo, and DeleteModel should collapse into nothing.
        """
        self.assertOptimizesTo(
            [
                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
                migrations.AlterModelTable("Foo", "woohoo"),
                alter_foo,
                migrations.DeleteModel("Foo"),
            ],
            [],
        )