Method test_slots_special

Lib/test/test_descr.py:1335–1372

(self)

        self.assertEqual(x, (1, 2, 3))

    def test_slots_special(self):
        # Testing __dict__ and __weakref__ in __slots__...
        class D(object):
            __slots__ = ["__dict__"]
        a = D()
        self.assertHasAttr(a, "__dict__")
        self.assertNotHasAttr(a, "__weakref__")
        a.foo = 42
        self.assertEqual(a.__dict__, {"foo": 42})
        with self.assertRaises(TypeError):
            weakref.ref(a)

        class W(object):
            __slots__ = ["__weakref__"]
        a = W()
        self.assertHasAttr(a, "__weakref__")
        self.assertNotHasAttr(a, "__dict__")
        with self.assertRaises(AttributeError):
            a.foo = 42
        self.assertIs(weakref.ref(a)(), a)

        class C1(W, D):
            __slots__ = []
        a = C1()
        self.assertHasAttr(a, "__dict__")
        self.assertHasAttr(a, "__weakref__")
        a.foo = 42
        self.assertEqual(a.__dict__, {"foo": 42})
        self.assertIs(weakref.ref(a)(), a)

        class C2(D, W):
            __slots__ = []
        a = C2()
        self.assertHasAttr(a, "__dict__")
        self.assertHasAttr(a, "__weakref__")
        a.foo = 42
        self.assertEqual(a.__dict__, {"foo": 42})
        self.assertIs(weakref.ref(a)(), a)

    @unittest.skipIf(_testcapi is None, 'need the _testcapi module')
    def test_slots_special_before_items(self):