public void AddReplyTest() { //Arrange var repo = new FakeMessageRepository(); var messageController = new MessageController(repo); var message = repo.Messages[0]; var beforeCountR = message.Replies.Count; // Act messageController.AddReply("Nicolette", "Molitor", "*****@*****.**", "I'll bring potatoes", message.MessageId); //Assert Assert.Equal(beforeCountR + 1, message.Replies.Count); }