'Ensure `old` complains when only `old` is defined.'

def test_get_old_defined(self):

    with warnings.catch_warnings(record=True) as recorded:
        warnings.simplefilter(u'ignore')
        class Manager(six.with_metaclass(RenameManagerMethods), ):
            def old(self):
                pass
        warnings.simplefilter(u'always')
        manager = Manager()
        manager.new()
        self.assertEqual(len(recorded), 0)
        manager.old()
        self.assertEqual(len(recorded), 1)
        msg = str(recorded.pop().message)
        self.assertEqual(msg, u'`Manager.old`    is    deprecated,    use    `new`    instead.')
