加入购物车库存判断

@@ -303,7 +303,8 @@ class Order extends Api
         $model = new GoodsSpec();
         $sku = $model::get($sku_id);
         if (!$sku) $this->error('规格已失效,请重新选择');
-        if ($sku['stock_num'] < $number) $this->error('已超出最大库存');
+        $cart_number = \app\api\model\Cart::where('sku_id',$sku_id)->sum('number');
+        if ($sku['stock_num'] < $number+$cart_number) $this->error('已超出最大库存');
         $this->success('SUCCESS');
     }