public void CreateConsumers_WhenSettingsIsValid_ShouldCreateConsumers() { //Arrange var numberOfConsumers = 3; var channelReaderMock = new Mock <ChannelReader <Message> >(); var subscriberMock = new Mock <IMQSubscriber>(); Func <IMessageHandler> messageHandlerGetterMock = () => new Mock <IMessageHandler>().Object; var settings = Options.Create(new TuttiFruitCandySettings { NumberOfConsumers = numberOfConsumers }); var sut = new ConsumerFactory(settings, channelReaderMock.Object, subscriberMock.Object, messageHandlerGetterMock); //Act var actionResult = sut.CreateConsumers(); //Assert actionResult.Count().Should().Be(numberOfConsumers); }