test_connection.py 文件源码

def test_set_isolation_level(self):
        conn = self.connect()
        curs = conn.cursor()

        levels = [
            ('read uncommitted',
                ext.ISOLATION_LEVEL_READ_UNCOMMITTED),
            ('read committed', ext.ISOLATION_LEVEL_READ_COMMITTED),
            ('repeatable read', ext.ISOLATION_LEVEL_REPEATABLE_READ),
            ('serializable', ext.ISOLATION_LEVEL_SERIALIZABLE),
        ]
        for name, level in levels:
            conn.set_isolation_level(level)

            # the only values available on prehistoric PG versions
            if conn.server_version < 80000:
                if level in (
                        ext.ISOLATION_LEVEL_READ_UNCOMMITTED,
                        ext.ISOLATION_LEVEL_REPEATABLE_READ):
                    name, level = levels[levels.index((name, level)) + 1]

            self.assertEqual(conn.isolation_level, level)

            curs.execute('show transaction_isolation;')
            got_name = curs.fetchone()[0]

            self.assertEqual(name, got_name)
            conn.commit()

        self.assertRaises(ValueError, conn.set_isolation_level, -1)
        self.assertRaises(ValueError, conn.set_isolation_level, 5)