Method test_descriptors_with_abstractmethod

Lib/test/test_abc.py:199–227

(self)

                self.assertTrue(isabstract(F))

        def test_descriptors_with_abstractmethod(self):
            class C(metaclass=abc_ABCMeta):
                @property
                @abc.abstractmethod
                def foo(self): return 3
                @foo.setter
                @abc.abstractmethod
                def foo(self, val): pass
            self.assertRaises(TypeError, C)
            class D(C):
                @C.foo.getter
                def foo(self): return super().foo
            self.assertRaises(TypeError, D)
            class E(D):
                @D.foo.setter
                def foo(self, val): pass
            self.assertEqual(E().foo, 3)
            # check that the property's __isabstractmethod__ descriptor does the
            # right thing when presented with a value that fails truth testing:
            class NotBool(object):
                def __bool__(self):
                    raise ValueError()
                __len__ = __bool__
            with self.assertRaises(ValueError):
                class F(C):
                    def bar(self):
                        pass
                    bar.__isabstractmethod__ = NotBool()
                    foo = property(bar)


        def test_customdescriptors_with_abstractmethod(self):