test_data_migrations.py 文件源码

def setUp(self):
        assert self.migrate_from and self.migrate_to, \
            "TestCase '{}' must define migrate_from and migrate_to properties".format(type(self).__name__)

        migrate_from = [(self.app, self.migrate_from)]
        migrate_to = [(self.app, self.migrate_to)]
        executor = MigrationExecutor(connection)
        old_apps = executor.loader.project_state(migrate_from).apps

        # Reverse to the original migration
        executor.migrate(migrate_from)

        self.setUpBeforeMigration(old_apps)

        # Run the migration to test
        executor = MigrationExecutor(connection)
        executor.loader.build_graph()  # reload.
        executor.migrate(migrate_to)

        self.apps = executor.loader.project_state(migrate_to).apps