Guidelines CPT: Changes slug from wp_content_guidelines to wp_guidelines

[iamchughmayank]

What?

Closes

See #76384

Renames the Content Guidelines custom post type slug from wp_content_guideline to wp_guideline.

Why?

Before the 22.7 release, the public-facing name was simplified from "Content Guidelines" to just "Guidelines" — recognizing the feature extends beyond content to design guidelines, coding standards, and more (announcement
post).

This PR aligns the internal CPT slug with that direction. As noted in the core review comments, wp_guideline follows WordPress's CPT naming convention (wp_block,
wp_template, wp_global_styles).

How?

Two changes:

• Gutenberg_Content_Guidelines_Post_Type::POST_TYPE constant → 'wp_guideline'
• Gutenberg_Content_Guidelines_Revisions_Controller constructor default → 'wp_guideline'

All other code references the POST_TYPE constant, so they pick up the change automatically. The rest_base remains content-guidelines. Meta keys (_content_guideline_*) are unchanged.

Testing Instructions

Setup: Boot up local WordPress using npm run wp-env start

1. Enable the experiment in Settings > Experiments under the label: "Guidelines"
2. Navigate to Settings > Guidelines.
3. Add text in the Copy and Images fields, click Save.
4. Refresh — verify saved guidelines load correctly.

Testing Instructions for Keyboard

No special steps for keyboard testing required

Screenshots or screencast

Before	After

No visual changes

Use of AI Tools

Claude Opus used for planning the task and creating summarised draft of PR description

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Co-authored-by: gziolo <gziolo@git.wordpress.org>

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[gziolo]

These atomic changes look good. I couldn't locate more occurrences of wp_content_guideline. The rest of the code will need to be updated to reflect the changes, like the names of both modified classes and files.

[gziolo]

I verified this change locally by running a new e2e suite I put up in #77192 against this branch. All three specs pass with the renamed wp_guideline slug, including the full Copy + Images save-and-refresh round-trip from the Testing Instructions here.

If you're open to it, it would be great to pull #77192 into your local branch (or rebase on top once it lands) and re-run npm run test:e2e -- test/e2e/specs/admin/guidelines.spec.js as part of the verification for this PR. That would make future CPT/REST/admin-page changes in this area much easier to validate and protect the feature from regressions while it's still experimental.

[iamchughmayank]

I verified this change locally by running a new e2e suite I put up in #77192 against this branch. All three specs pass with the renamed wp_guideline slug, including the full Copy + Images save-and-refresh round-trip from the Testing Instructions here.

If you're open to it, it would be great to pull #77192 into your local branch (or rebase on top once it lands) and re-run npm run test:e2e -- test/e2e/specs/admin/guidelines.spec.js as part of the verification for this PR. That would make future CPT/REST/admin-page changes in this area much easier to validate and protect the feature from regressions while it's still experimental.

Thanks! I pulled the linked PR with E2Es and the tests are working fine ( #77192 (comment) )