test_memoryio.py 文件源码

def test_pickling(self):
        buf = self.buftype("1234567890")
        memio = self.ioclass(buf)
        memio.foo = 42
        memio.seek(2)

        class PickleTestMemIO(self.ioclass):
            def __init__(me, initvalue, foo):
                self.ioclass.__init__(me, initvalue)
                me.foo = foo
            # __getnewargs__ is undefined on purpose. This checks that PEP 307
            # is used to provide pickling support.

        # Pickle expects the class to be on the module level. Here we use a
        # little hack to allow the PickleTestMemIO class to derive from
        # self.ioclass without having to define all combinations explicitly on
        # the module-level.
        import __main__
        PickleTestMemIO.__module__ = '__main__'
        PickleTestMemIO.__qualname__ = PickleTestMemIO.__name__
        __main__.PickleTestMemIO = PickleTestMemIO
        submemio = PickleTestMemIO(buf, 80)
        submemio.seek(2)

        # We only support pickle protocol 2 and onward since we use extended
        # __reduce__ API of PEP 307 to provide pickling support.
        for proto in range(2, pickle.HIGHEST_PROTOCOL + 1):
            for obj in (memio, submemio):
                obj2 = pickle.loads(pickle.dumps(obj, protocol=proto))
                self.assertEqual(obj.getvalue(), obj2.getvalue())
                self.assertEqual(obj.__class__, obj2.__class__)
                self.assertEqual(obj.foo, obj2.foo)
                self.assertEqual(obj.tell(), obj2.tell())
                obj.close()
                self.assertRaises(ValueError, pickle.dumps, obj, proto)
        del __main__.PickleTestMemIO