Comments: Catch PHP errors when malformed POST is submitted

[tbradsha]

I saw these errors in the WP Cloud logs:

PHP Fatal error: Uncaught TypeError: str_contains(): Argument #1 ($haystack) must be of type string, array given in /wordpress/plugins/jetpack/14.7/modules/comments/comments.php:652
PHP Fatal error: Uncaught TypeError: hash_equals(): Argument #2 ($user_string) must be of type string, array given in /wordpress/plugins/jetpack/14.7/modules/comments/comments.php:666

The method is triggered by the pre_comment_on_post action. As we know, anything can happen in actions, so I'm not sure if $POST was manipulated somewhere there or by some other thing that sent bad data, but this PR adds two is_string() checks to prevent the fatal.

Proposed changes:

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
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Jetpack product discussion

Does this pull request change what data or activity we track or use?

Testing instructions:

I'm not sure the best way to reproduce this. 🤷

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WoA dev site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin (Jetpack), and enable the fix/jetpack/php_errors_with_malformed_POST branch.
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bin/jetpack-downloader test jetpack fix/jetpack/php_errors_with_malformed_POST

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[github-actions]

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Jetpack plugin:

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[jp-launch-control]

Code Coverage Summary

This PR did not change code coverage!

That could be good or bad, depending on the situation. Everything covered before, and still is? Great! Nothing was covered before? Not so great. 🤷

Full summary · PHP report · JS report