public void Should_Success_ProductSKU_When_latestCodeIsEmpty()
        {
            var latestcode    = "";
            var codeGenerator = DocumentCodeGenerator.ProductSKU(latestcode);

            Assert.NotEmpty(codeGenerator);
        }
        public void Should_Success_Intantiate_When_yearNowCode_NotEqual_yearCode()
        {
            var monthNowCode  = DateTime.Now.Month.ToString().PadLeft(2, '0');
            var latestcode    = "00" + monthNowCode;
            var codeGenerator = DocumentCodeGenerator.ProductSKU(latestcode);

            Assert.NotEmpty(codeGenerator);
        }