wpcomsh: footer credit

[mgozdis]

Fixes DOTTHEM-343

Proposed changes

• Adds a word boundary to prevent improper replacement of the first instance of "theme" within a footer.php when the active theme does not follow coding standards and have a valid style.css.
• We may want to also just early return entirely if the theme name can't be detected.

Related product discussion/links

• https://linear.app/a8c/issue/DOTTHEM-343/first-instance-of-theme-is-replaced-with-an-empty-string-in-footerphp

Testing instructions

1. Install and activate the following test theme manually via SFTP/SSH (wp-admin has guards to prevent installing a theme with invalid style.css) wp theme activate testtheme - testtheme.zip
2. Review the footer area on the frontend and see if the screenshot.png image displays or is broken.
3. Review the source code of the page in your browser and search for wp-content/s/ to ensure an improper string replacement hasn't been made.

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

No

[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 (WordPress.com Site Helper), and enable the DOTTHEM-343-footer-credit branch.

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

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Wpcomsh plugin:

• Next scheduled release: Atomic deploys happen twice daily on weekdays (p9o2xV-2EN-p2)

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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

[mgozdis]

Closing this to create a new PR instead to check for an empty theme name as this doesn't work.