public void GetAllImages_ReturnsOkObjectResult_WithListOfImages() { // Arrange mockRepo.Setup(repo => repo.GetAllImages()).Returns(GetTestImages()); var controller = new ImagesController(mockRepo.Object, mockGCS.Object, mockMapper.Object); // Act var result = controller.GetAllImages(); // Assert var okObjectResult = Assert.IsType <OkObjectResult>(result.Result); var model = Assert.IsAssignableFrom <IEnumerable <Image> >( okObjectResult.Value); Assert.Equal(GetTestImages().Count, model.Count()); }