ShipmentItem::get

protected function get(BitrixSaleShipmentItem $shipmentItem, array $fields=[])
{
	/** @var ShipmentItemCollection $collectionShipmentItems */
	$collectionShipmentItems = $shipmentItem->getCollection();
	/** @var BitrixSaleShipment $shipment */
	$shipment = $collectionShipmentItems->getShipment();
	/** @var ShipmentCollection $collectionShipments */
	$collectionShipments = $shipment->getCollection();
	$order = $collectionShipments->getOrder();

	$shipments = $this->toArray($order, $fields)['ORDER']['SHIPMENTS'];
	foreach ($shipments as $shipment)
	{
		foreach ($shipment['SHIPMENT_ITEMS'] as $item)
		{
			if($item['ID']==$shipmentItem->getId())
			{
				return $item;
			}
		}
	}
	return [];
}