[4.2.3]: getDiscountByCode(): Argument #1 ($code) must be of type string, null given

[kaspar-allenbach]

What happened?

Description

I migrated to craft 4 according to the migration guide and everything went well.

Steps to reproduce

1. Migrate to craft 4
2. Add something into the cart
3. On the Cart template there is the following error on the cart page:

craft\commerce\services\Discounts::getDiscountByCode(): Argument #1 ($code) must be of type string, null given, called in /Users/atelierworkstation/Documents/git-local/atelier-shop/vendor/twig/twig/src/Extension/CoreExtension.php on line 1607

Stack Trace

TypeError: craft\commerce\services\Discounts::getDiscountByCode(): Argument #1 ($code) must be of type string, null given, called in /vendor/twig/twig/src/Extension/CoreExtension.php on line 1607 and defined in /vendor/craftcms/commerce/src/services/Discounts.php:382
Stack trace:
#0 /vendor/twig/twig/src/Extension/CoreExtension.php(1607): craft\commerce\services\Discounts->getDiscountByCode(NULL)
#1 /vendor/craftcms/cms/src/helpers/Template.php(110): twig_get_attribute(Object(craft\web\twig\Environment), Object(Twig\Source), Object(craft\commerce\services\Discounts), 'getDiscountByCo...', Array, 'method', false, false)
#2 /storage/runtime/compiled_templates/48/4814239c41dedafc8391a1b70140a2d5.php(59): craft\helpers\Template::attribute(Object(craft\web\twig\Environment), Object(Twig\Source), Object(craft\commerce\services\Discounts), 'getDiscountByCo...', Array, 'method')
#3 /vendor/twig/twig/src/Template.php(171): __TwigTemplate_fc9f511b5bd2fbee71b2e2d81933d7e6->block_main(Array, Array)
#4 /storage/runtime/compiled_templates/1c/1c64b2042fe0dfe96716d9e6f05f4b31.php(332): Twig\Template->displayBlock('main', Array, Array)
#5 /vendor/twig/twig/src/Template.php(171): __TwigTemplate_f939a9e67f563b6befd17836bf1b98ec->block_body(Array, Array)
#6 /storage/runtime/compiled_templates/1c/1c64b2042fe0dfe96716d9e6f05f4b31.php(304): Twig\Template->displayBlock('body', Array, Array)
#7 /vendor/twig/twig/src/Template.php(394): __TwigTemplate_f939a9e67f563b6befd17836bf1b98ec->doDisplay(Array, Array)
#8 /vendor/twig/twig/src/Template.php(367): Twig\Template->displayWithErrorHandling(Array, Array)
#9 /storage/runtime/compiled_templates/06/06430c5474c19a0e396cb203c104bc63.php(53): Twig\Template->display(Array, Array)
#10 /vendor/twig/twig/src/Template.php(394): __TwigTemplate_f1d0c467d20bbb79bcf56d6786094c73->doDisplay(Array, Array)
#11 /vendor/twig/twig/src/Template.php(367): Twig\Template->displayWithErrorHandling(Array, Array)
#12 /storage/runtime/compiled_templates/48/4814239c41dedafc8391a1b70140a2d5.php(46): Twig\Template->display(Array, Array)
#13 /vendor/twig/twig/src/Template.php(394): __TwigTemplate_fc9f511b5bd2fbee71b2e2d81933d7e6->doDisplay(Array, Array)
#14 /vendor/twig/twig/src/Template.php(367): Twig\Template->displayWithErrorHandling(Array, Array)
#15 /vendor/twig/twig/src/Template.php(379): Twig\Template->display(Array)
#16 /vendor/twig/twig/src/TemplateWrapper.php(40): Twig\Template->render(Array, Array)
#17 /vendor/twig/twig/src/Environment.php(277): Twig\TemplateWrapper->render(Array)
#18 /vendor/craftcms/cms/src/web/View.php(451): Twig\Environment->render('purchase/cart', Array)
#19 /vendor/craftcms/cms/src/web/View.php(504): craft\web\View->renderTemplate('purchase/cart', Array)
#20 /vendor/craftcms/cms/src/web/TemplateResponseFormatter.php(56): craft\web\View->renderPageTemplate('purchase/cart', Array, 'site')
#21 /vendor/yiisoft/yii2/web/Response.php(1098): craft\web\TemplateResponseFormatter->format(Object(craft\web\Response))
#22 /vendor/craftcms/cms/src/web/Response.php(286): yii\web\Response->prepare()
#23 /vendor/yiisoft/yii2/web/Response.php(339): craft\web\Response->prepare()
#24 /vendor/yiisoft/yii2/base/Application.php(390): yii\web\Response->send()
#25 /www/index.php(32): yii\base\Application->run()
#26 {main}

Craft CMS version

4.4.3

Craft Commerce version

4.2.3

PHP version

8.1.1

Operating system and version

No response

Database type and version

No response

Image driver and version

No response

Installed plugins and versions

[kaspar-allenbach]

Nothing?

[pdaleramirez]

@kaspar-allenbach It seems to be a templating issue. You are calling the getDiscountByCode somewhere in the site template without passing a value. Can you test this on the example templates to see if you are still having issues?

[lukeholder]

@kaspar-allenbach Can you try craft.commerce.discounts.getDiscountByCode(cart.couponCode ?? '') in your example templates. The ?? '' will pass a string if no coupon is on the cart.

We will relax the getDiscountByCode's param type so that null can be passed again.