test_migrations.py 文件源码

def test_add_field(self):
        project_state = self.set_up_test_model()
        operation = migrations.AddField(
            'Pony',
            'height',
            models.FloatField(null=True, default=5)
        )
        new_state = project_state.clone()
        operation.state_forwards('tests', new_state)
        self.assertColumnNotExists('tests_pony', 'height')
        with connection.schema_editor() as editor:
            operation.database_forwards('tests', editor, project_state, new_state)
        self.assertColumnExists('tests_pony', 'height')
        with connection.schema_editor() as editor:
            operation.database_backwards('tests', editor, new_state, project_state)
        self.assertColumnNotExists('tests_pony', 'height')