user.php

См. документацию.

<?php
 
namespace Bitrix\Sale\Discount\Context;
 
class User extends BaseContext
{
    public function __construct($user)
    {
        $this->userId = static::resolveUserId($user);
        $this->setUserGroups(\CUser::getUserGroup($this->userId));
    }

    private static function resolveUserId($user)
    {
        if ($user instanceof \CUser)
        {
            return (int)$user->getId();
        }
        elseif(is_numeric($user) && (int)$user > 0)
        {
            return (int)$user;
        }
 
        return static::GUEST_USER_ID;
    }
}