public async Task GetPhotoByIdAndAnyPhotoColumnNameShouldReturnNotFound() { // Arrange var id = 45; string coldwater = "coldwater"; // hotwater, gas, energy, heat; mockRepo.Setup(x => x.Photo).Returns(_photoRepoMock.Object); _photoRepoMock.Setup(x => x.GetPhotoByIdOneColumn(id, coldwater)).ReturnsAsync(() => null); // Act var result = await _sut.GetPhotoByIdAndAnyPhotoColumnName(id, coldwater); // Assert Assert.IsType <NotFoundResult>(result); Assert.IsNotType <OkObjectResult>(result); }