public void apply_event() { _stream.Setup(x => x.Add(Moq.It.IsAny <IEvent>(), Moq.It.IsAny <IDictionary <string, string> >())); _entity.ApplyEvent(); _stream.Verify(x => x.Add(Moq.It.IsAny <IEvent>(), Moq.It.IsAny <IDictionary <string, string> >()), Moq.Times.Once); }