[Issue] Declare optional argument after required.

[m2-assistant]

This issue is automatically created based on existing pull request: #31275: Declare optional argument after required.

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Description

This prevents PHP fatal error when a plugin is added to the one of parent classes.

Manual testing scenarios

1. Create a plugin for \Magento\Framework\View\Element\BlockInterface.
2. Navigate to Content > Pages.

Plugin example

Open Magento/Cms/etc/di.xml and add the following code:

<type name="Magento\Framework\View\Element\BlockInterface">
    <plugin name="cms_plugin" type="Magento\Cms\Plugin\Block" />
</type>

Create Magento\Cms\Plugin\Block class:

<?php

namespace Magento\Cms\Plugin;

class Block
{
    /**
     * @param mixed $subject
     * @param mixed $result
     * @return mixed
     */
    public function afterToHtml(
        $subject,
        $result
    ) {
        return $result;
    }
}

Actual Result: ✖️ A fatal error will be rendered: 'Error: Cannot instantiate interface Magento\Framework\Data\OptionSourceInterface'Magento\Framework\Data\OptionSourceInterface

Expected Result: ✔️ The page is successfully loaded

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds are green)

[magento-engcom-team]

✅ Confirmed by @engcom-Alfa
Thank you for verifying the issue. Based on the provided information internal tickets MC-39947 were created

Issue Available: @engcom-Alfa, You will be automatically unassigned. Contributors/Maintainers can claim this issue to continue. To reclaim and continue work, reassign the ticket to yourself.

[magento-engcom-team]

Hi @m2-assistant[bot]. Thank you for your report.
The issue has been fixed in #31275 by @vovayatsyuk in 2.4-develop branch
Related commit(s):

• b54e7ae78916d215288b4ddb89d7351b5e183cef

The fix will be available with the upcoming 2.4.3 release.