Forms: Use Core buttons instead of Jetpack buttons

[lezama]

Fixes #

Proposed changes

• Switch Contact-Form submit control to Core Buttons – the block now inserts and recognises the Gutenberg Core Buttons → Button block, gaining all improvements made upstream and a more intuitive editing experience.
• Variations & fallback – every form variation now uses a Core Button (<button type="submit"> with jetpack-form-submit-button class).
• Interactivity – front-end render filter adds data-wp-class--is-submitting & data-wp-bind--aria-disabled so the Core Button integrates with Jetpack Forms’ submit/disable logic.
• Spinner – loading indicator implemented by CSS ::after pseudo-element (no extra markup).
• Backward compatibility – legacy forms that still contain a Jetpack Button continue to work unchanged; detection paths for wp-block-jetpack-button remain intact.

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?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

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

Testing instructions

1. Existing post smoke-test

   • Open a post containing a Contact Form created before this patch (uses Jetpack Button).
   • Confirm there are no editor errors; publish / update.
   • View front-end and submit the form – it should behave as it always did.

2. New form

   • Insert a fresh Contact Form block.
   • Verify the submit control is a Core Button in a Core Buttons wrapper.
   • Publish and submit on the front-end – spinner, disable state and success/error handling should work.

3. Variations

   • Insert each Contact-Form variation (RSVP, Registration, Feedback, etc.).
   • Confirm each uses a Core Button and submits correctly.

4. Editor layout

   • Editing experience should respect the different core/block options when saving.

[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 feature/replace-jetpack-buttons-with-core-buttons branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack feature/replace-jetpack-buttons-with-core-buttons

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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[jp-launch-control]

Code Coverage Summary

Coverage changed in 3 files.

File	Coverage	Δ%	Δ Uncovered
projects/packages/forms/src/blocks/contact-form/class-contact-form-block.php	285/601 (47.42%)	-0.97%	12 💔
projects/packages/forms/src/blocks/contact-form/edit.js	0/234 (0.00%)	0.00%	3 ❤️‍🩹
projects/packages/forms/src/contact-form/class-contact-form.php	586/1062 (55.18%)	-0.10%	2 ❤️‍🩹

Full summary · PHP report · JS report

_{If appropriate, add one of these labels to override the failing coverage check: Covered by non-unit tests Use to ignore the Code coverage requirement check when E2Es or other non-unit tests cover the code Coverage tests to be added later Use to ignore the Code coverage requirement check when tests will be added in a follow-up PR I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage.}

[simison]

Suggested change

	text: __( 'Contact Us', 'jetpack-forms' ),
	text: __( 'Contact us', 'jetpack-forms' ),

Good time to switch to sentence case while we're here.

Although this would need E2E update in calypso 🤦

https://github.com/Automattic/wp-calypso/blob/4c7fb9d7fc5047695e22b12a4708dbb9fb27f8e3/packages/calypso-e2e/src/lib/blocks/block-flows/contact-form.ts#L73

[simison]

Great thing about using core buttons is that they will soon also support pseudo classes like :hover

• [Button Block]: add support for pseudo elements for the block and its variations on theme.json WordPress/gutenberg#71418

[simison]

Rebased

[enejb]

I noticed a couple of things while testing this PR.

1. You are not able to set the width of the buttons block. ( the wrapper block ) This was unexpected since it removed the ability to place a field next to the button.
2. You are able to put multiple button blocks inside the buttons wrapper block. This was unexpected since I would expect there to be only one submit button. I think a reset or cancel or clear button might work be useful but there was no way to create them. (this feature could be done in a future PR and not in this one)
3. I didn't see the spinner that I am used to seeing when the form is submitting.

Nice work Miguel!

[lezama]

You are not able to set the width of the buttons block. ( the wrapper block ) This was unexpected since it removed the ability to place a field next to the button.

That was more of a hack. The idea is that you should use one of the stacking blocks, like columns or rows. Since we are using core buttons, we should take advantage of how they interact with those core layout blocks now.

[simison]

Can we use the core button without its container?

Separately, do I remember wrong or does WP templating allow limiting the number of certain type blocks as inner blocks?

[lezama]

Can we use the core button without its container?

Looks like not: https://github.com/WordPress/gutenberg/blob/trunk/packages/block-library/src/button/block.json#L7