public ActionResult EditProduct(int productId)
        {
            var productDataService = new ProductDataService();
            var product            = productDataService.GetProductById(productId);

            return(PartialView(new ProductViewModel(product)));
        }
        public void GetProductById()
        {
            //Arrange
            var service = new ProductDataService(repository);

            //Act
            var product = service.GetProductById(1);

            //Assert
            Assert.IsNotNull(product);
        }