public void Registered_handlers_recieve_raised_events()
        {
            var bus          = new InMemoryMessageBus();
            var eventHandler = Substitute.For <IEventListener>();
            var fakeEvent    = new FakeEvent();

            bus.RegisterEventHandler(eventHandler);

            bus.RaiseEvent <FakeEvent>(fakeEvent);

            eventHandler.Received().Handle(fakeEvent);
        }