public async Task RemoveTest() { var mockSet = new Mock <DbSet <ShowRoomViewer> >().SetupList(_sampleList); var mockContext = new Mock <LiveShowDBContext>(); mockContext.Setup(x => x.ShowRoomViewer).Returns(mockSet.Object); var mockSvc = new ShowRoomViewerSvc(mockContext.Object); await mockSvc.Remove(new ShowRoomViewerDto() { UserId = 1, ShowRoomId = 1 }); mockSet.Verify(x => x.Remove(It.IsAny <ShowRoomViewer>()), Times.Once()); mockContext.Verify(x => x.SaveChanges(), Times.Once()); }