calculator.php

См. документацию.

<?php
 
namespace Sale\Handlers\Delivery\Spsr;
 
use Bitrix\Main\Error;
use Bitrix\Sale\Result;
use Bitrix\Sale\Shipment;

class Calculator
{
    public static function calculate(Shipment $shipment, $additional)
    {
        return (new Result())->addError(new Error('The company no longer exists'));
    }
}