public void GivenIHaveRegisteredForAMessageType_WhenIClearAllRegistrations_ThenNoMoreMessagesAreReceived() { // Arrange var messageBroker = new MessageBroker(); bool messageReceived = false; messageBroker.Register(this, new Action <TestMessage>(message => messageReceived = true)); messageBroker.Clear(); // Act messageBroker.Send(new TestMessage()); // Assert Assert.That(messageReceived, Is.False); }