test_weakref.py 文件源码

def test_equality(self):
        def _eq(a, b):
            self.assertTrue(a == b)
            self.assertFalse(a != b)
        def _ne(a, b):
            self.assertTrue(a != b)
            self.assertFalse(a == b)
        x = Object(1)
        y = Object(1)
        a = weakref.WeakMethod(x.some_method)
        b = weakref.WeakMethod(y.some_method)
        c = weakref.WeakMethod(x.other_method)
        d = weakref.WeakMethod(y.other_method)
        # Objects equal, same method
        _eq(a, b)
        _eq(c, d)
        # Objects equal, different method
        _ne(a, c)
        _ne(a, d)
        _ne(b, c)
        _ne(b, d)
        # Objects unequal, same or different method
        z = Object(2)
        e = weakref.WeakMethod(z.some_method)
        f = weakref.WeakMethod(z.other_method)
        _ne(a, e)
        _ne(a, f)
        _ne(b, e)
        _ne(b, f)
        del x, y, z
        gc.collect()
        # Dead WeakMethods compare by identity
        refs = a, b, c, d, e, f
        for q in refs:
            for r in refs:
                self.assertEqual(q == r, q is r)
                self.assertEqual(q != r, q is not r)