public async void Shelf_Update_length()
        {
            Mock <IProductInventoryRepository> productInventoryRepository = new Mock <IProductInventoryRepository>();

            productInventoryRepository.Setup(x => x.Get(It.IsAny <int>())).Returns(Task.FromResult(new ProductInventory()));

            var validator = new ApiProductInventoryRequestModelValidator(productInventoryRepository.Object);
            await validator.ValidateUpdateAsync(default(int), new ApiProductInventoryRequestModel());

            validator.ShouldHaveValidationErrorFor(x => x.Shelf, new string('A', 11));
        }
        public async void Shelf_Create_null()
        {
            Mock <IProductInventoryRepository> productInventoryRepository = new Mock <IProductInventoryRepository>();

            productInventoryRepository.Setup(x => x.Get(It.IsAny <int>())).Returns(Task.FromResult(new ProductInventory()));

            var validator = new ApiProductInventoryRequestModelValidator(productInventoryRepository.Object);
            await validator.ValidateCreateAsync(new ApiProductInventoryRequestModel());

            validator.ShouldHaveValidationErrorFor(x => x.Shelf, null as string);
        }