public async Task UpdatePhotoTags() { var photoIds = _fixture.CreateMany <int>(5); var tagStates = _fixture.CreateMany <TagState>(5); var batchUpdate = new BatchUpdateTags { PhotoIds = photoIds.ToList(), TagStates = tagStates.ToList() }; _photosService.Setup(m => m.UpdatePhotoTags(It.IsAny <List <int> >(), It.IsAny <List <string> >(), It.IsAny <List <int> >())); var response = await _tagsController.TagPhotos(batchUpdate); _photosService.Verify(m => m.UpdatePhotoTags(It.IsAny <List <int> >(), It.IsAny <List <string> >(), It.IsAny <List <int> >()), Times.Once); Assert.IsType <OkResult>(response); }