public async void UpdatebyProduct_CallsUpdatebyProductOnMockRepo_ReturnsCreatedObjectResult()
        {
            //Arrange
            int productId  = 1;
            var newProduct = new Product()
            {
            };

            mockRepo.Setup(repo => repo.UpdatebyProduct(newProduct)).Returns(Task.FromResult <Product>(newProduct));

            //Act
            var result = await controller.UpdatebyProduct(productId, newProduct);

            var resultObj = result as OkObjectResult;

            //Asset
            mockRepo.Verify(repo => repo.UpdatebyProduct(newProduct), Times.Once);

            Assert.NotNull(resultObj);
            Assert.Equal(200, resultObj.StatusCode);
        }