public void Should_dispatch_message_to_registered_handler() { const string messageType = "messageType"; IMessageHandler messageHandler = CreateHandler(messageType); IMessage message = CreateMessage(messageType); _subject.Register(messageHandler); _subject.Dispatch(message); messageHandler.AssertWasCalled(h => h.Handle(message)); _defaultHandler.AssertWasNotCalled(h => h.Handle(Arg <IMessage> .Is.Anything)); }