PrestaShop Error Declaration of Cart::getPackageShippingCost

On a PrestaShop site, i get error message

(1/1) ContextErrorException
Warning: Declaration of Cart::getPackageShippingCost($id_carrier = NULL, $use_tax = true, ?Country $default_country = NULL, $product_list = NULL, $id_zone = NULL) should be compatible with CartCore::getPackageShippingCost($id_carrier = NULL, $use_tax = true, ?Country $default_country = NULL, $product_list = NULL, $id_zone = NULL, bool $keepOrderPrices = false)

in Cart.php line 1021
at ErrorHandler->handleError(2, 'Declaration of Cart::getPackageShippingCost($id_carrier = NULL, $use_tax = true, ?Country $default_country = NULL, $product_list = NULL, $id_zone = NULL) should be compatible with CartCore::getPackageShippingCost($id_carrier = NULL, $use_tax = true, ?Country $default_country = NULL, $product_list = NULL, $id_zone = NULL, bool $keepOrderPrices = false)', '/var/www/vhosts/site.com/httpdocs/override/classes/Cart.php', 1021, array('className' => 'Cart', 'classDir' => '/var/www/vhosts/site.com/httpdocs/'))
in PrestaShopAutoload.php line 152

To fix this error, edit the file (location of the file depends on your hosting provider, on cpanel servers, it is public_html folder, on Plesk servers, it is httpdocs).

override/classes/Cart.php

Find line

public function getPackageShippingCost($id_carrier = null, $use_tax = true, Country $default_country = null, $product_list = null, $id_zone = null)

Replace with

public function getPackageShippingCost($id_carrier = null, $use_tax = true, Country $default_country = null, $product_list = null, $id_zone = null, $keepOrderPrices = false)

This is because orderide class have improper function definiation, this may be due to some outdated PrestaShop modules.

See PrestaShop