Merge branch 'feature/20201112_套餐价格计算_yu.sun' into qa

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

@@ -86,7 +86,8 @@ public class SetMealCalculation {
                             comboxmaterialPrice+= null !=  materialGoods.getFinalPrice() ? materialGoods.getFinalPrice() * cartGoods.getQty() : 0;
                         }
                     }
-                    comboxGoods.setAmount(comboxGoods.getAmount()+comboxmaterialPrice);
+                    comboxGoods.setAmount((null == comboxGoods.getAmount() ? 0 :
+                            comboxGoods.getAmount())+comboxmaterialPrice);
                     materialPrice = materialPrice + comboxmaterialPrice;
                 }
             }