def test_observer(self):
observer = Observer()
self.assertEqual(0, observer.count())
# Check for no crash
observer.notify()
observer.clear()
self.assertRaises(KeyError, observer.remove, 'no exist')
values = {}
def func(value):
values['value'] = value
observer.add(func)
self.assertEqual(1, observer.count())
observer.notify('a')
self.assertEqual('a', values['value'])
observer.clear()
observer.notify()
self.assertEqual(0, observer.count())
