public void DeletebyProduct_CallsDeleteMethodbyProductOnMockRepoWithCorrectId_ReturnsOkObject()
{
//Arrange
long expectedId = 12;
mockRepo.Setup(repo => repo.DeletebyProduct(expectedId));
//Act
var result = controller.DeletebyProduct(expectedId);
var resultObj = result as OkObjectResult;
var model = resultObj.Value as String;
//Assert
mockRepo.Verify(repo => repo.DeletebyProduct(expectedId), Times.Once);
Assert.IsType <OkObjectResult>(result);
Assert.Equal(200, resultObj.StatusCode);
Assert.Equal(model, $"Product at {expectedId} is deleted");
}