test_refcounts.py 文件源码

def test_1(self):
        try:
            from sys import getrefcount as grc
        except ImportError:
            return unittest.skip("no sys.getrefcount()")

        f = dll._testfunc_callback_i_if
        f.restype = ctypes.c_int
        f.argtypes = [ctypes.c_int, MyCallback]

        def callback(value):
            #print "called back with", value
            return value

        self.assertEqual(grc(callback), 2)
        cb = MyCallback(callback)

        self.assertTrue(grc(callback) > 2)
        result = f(-10, cb)
        self.assertEqual(result, -18)
        cb = None

        gc.collect()

        self.assertEqual(grc(callback), 2)