def test_link_message_to_user(self):
feed = Feed()
username = "******"
message = "Hello!"
feed.post_message(username, message)
actual_messages = feed.get_messages_of(username)
self.assertEqual([message], actual_messages)
def test_non_existing_user(self):
feed = Feed()
self.assertEqual([], feed.get_messages_of("John"))