Bug report: 100% discount causes a fatal error and makes the website unusable

-- HikaShop version -- : 6.0.0
-- Joomla version -- : 4.4.3
-- PHP version -- : 8.2
-- Browser(s) name and version -- : Chrome
-- Error-message(debug-mod must be tuned on) -- : Attempt to assign property "tax_amount" on null

Hi,

we have the following discount code set up in HikaShop:
prnt.sc/MqVO4V_4aAYr

In combination with particular products in the cart, it results in the following error:

Attempt to assign property "tax_amount" on null

Screenshot:
prnt.sc/yvZW_qPkwnz_

The user can no longer use the website at all as every page visit results in the same error.

Stack trace:
prnt.sc/vOAmxB1yOVZ9

Our developer investigated this and determined it is indeed a bug.

Here is what he said:

For a quick fix, I updated the file:
\\administrator\components\com_hikashop\classes\discount.php and around line 703 added:

if ( ! isset( $cart->coupon->total->prices[0]->taxes ) && isset ( $cart->coupon->total->prices[0]->taxes_without_discount ) ) $cart->coupon->total->prices[0]->taxes = $cart->coupon->total->prices[0]->taxes_without_discount; # seyi_code