gistfile1.txt

 public function addOrderItem($orderItem, $qtyFlag = null)
    {
        /* @var $orderItem \Magento\Sales\Model\Order\Item */
        if ($orderItem->getParentItem() === null) {
            $storeId = $this->_storeManager->getStore()->getId();
            try {
                $product = $this->productRepository->getById($orderItem->getProductId(), false, $storeId);
            } catch (NoSuchEntityException $e) {
                return $this;
            }
            $info = $orderItem->getProductOptionByCode('info_buyRequest');
            $info = new \Magento\Framework\DataObject($info);
            if ($qtyFlag === null) {
                $info->setQty($orderItem->getQtyOrdered());
            } else {
                $info->setQty(1);
            }

            $this->addProduct($product, $info);
        }
        return $this;
    }