fix bug

shopping-cart-application-service/src/main/java/cn/freemud/service/impl/mcoffee/ShoppingCartMCoffeeServiceImpl.java

@@ -237,7 +237,7 @@ public class ShoppingCartMCoffeeServiceImpl {
                     //使用券的是，如果购物车已经存在这个券，先清除，再添加
                     cartGoods.setQty(0);
                 }
-                if (StringUtils.isNotEmpty(goodsId) && StringUtils.isBlank(couponCode) && goodsId.equals(cartGoods.getSkuId())) {
+                if (StringUtils.isNotEmpty(goodsId) && StringUtils.isNotEmpty(couponCode) && goodsId.equals(cartGoods.getSkuId())) {
                     if (cartGoods.getQty() > 1 ){
                         cartGoods.setQty(cartGoods.getQty() - 1);
                     }else {