OrderBuilderRest::prepareDataForSetFields

protected function prepareDataForSetFields(BitrixSaleShipment $shipment, $items)
{
	$result = new Result();
	$shipmentItemCollection = $shipment->getShipmentItemCollection();

	//only for update shipmentItem, where BASKET_ID is imutable
	if(isset($items['ORDER_DELIVERY_BASKET_ID']) && intval($items['ORDER_DELIVERY_BASKET_ID']) > 0)
	{
		if (!$shipmentItem = $shipmentItemCollection->getItemById($items['ORDER_DELIVERY_BASKET_ID']))
		{
			$result->addError( new Error( 'SALE_ORDER_SHIPMENT_BASKET_ORDER_DELIVERY_ID_NOT_FOUND'));
		}
		else
		{
			/** @var ShipmentItem $shipmentItem */
			$items['BASKET_ID'] = $shipmentItem->getBasketId();
		}
	}
	return $result->setData([$items]);
}