库存不足时 允许减操作

app/Service/v3/Implementations/ShopCartUpdateService.php

@@ -69,8 +69,21 @@ class ShopCartUpdateService implements ShopCartUpdateServiceInterface
 
         if($goodsCheck !== true)
         {
+            if($goodsCheck === ErrorCode::GOODS_ACTIVITY_INVENTORY_ERROR){
+                $shopcartNum = ShoppingCart::query()
+                    ->where([
+                        'user_id' => $userId,
+                        'goods_id' => $goodsId,
+                        'activity_type' => $activityType
+                    ])
+                    ->value('num');
+                if($num > $shopcartNum){
                     throw new ErrorCodeException($goodsCheck);
                 }
+            }else{
+                throw new ErrorCodeException($goodsCheck);
+            }
+        }
 
         $shoppingCart = ShoppingCart::query()->lockForUpdate()->updateOrCreate(
 				[