实际支付金额增加判断

share-system/src/main/java/share/system/service/impl/SOrderServiceImpl.java

@@ -1057,7 +1057,13 @@ public class SOrderServiceImpl extends ServiceImpl<SOrderMapper, SOrder> impleme
                     throw new BaseException("总金额小于优惠券最小使用金额");
                 }
                 priceResponse.setCouponFee(consumerCoupon.getSubPrice());
-                priceResponse.setPayFee(priceResponse.getTotalFee().subtract(consumerCoupon.getSubPrice()));
+                BigDecimal subtract = priceResponse.getTotalFee().subtract(consumerCoupon.getSubPrice());
+                //判断是否为负数
+                if (subtract.compareTo(BigDecimal.ZERO) < 0) {
+                    priceResponse.setPayFee(BigDecimal.ZERO);
+                } else {
+                    priceResponse.setPayFee(subtract);
+                }
                 break;
             case DURATION://TODO 时长券
                 break;