Subscribe and button blocks: Add email rendering for WC Email Editor

[allilevine]

Fixes https://linear.app/a8c/issue/CML-770/fix-subscribe-block
Fixes https://linear.app/a8c/issue/CML-860/fix-email-rendering-for-buttons

Proposed changes:

This PR adds email rendering for the Jetpack button block, using the core/button block email rendering already available in the WC Email Editor package. We then use the button block email rendering in the subscribe block. Also adds tests.

Known issue: the core button block rendering doesn't support gradients. We can follow up on that in the package.

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

https://linear.app/a8c/project/switch-to-centralized-email-rendering-solution-aacb0b060431/issues?layout=list&ordering=priority&grouping=workflowState&subGrouping=none&showCompletedIssues=all&showSubIssues=true&showTriageIssues=false

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

N/A

Testing instructions:

• Apply these changes to your sandbox using bin/jetpack-downloader test jetpack add/subscribe-block-wc-email-rendering.
• Sandbox the API and turn on write access.
• Add the wc-email-editor sticker to a test site. See PCYsg-eQj-p2
• Create a post with a button block and a subscribe block. Try changing the button styles.
• Send yourself a test email.
• Click the buttons in the email.

Notes:

• To test with a WoA dev or self-hosted site you'll need to set it up to connect to your sandbox.

[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 add/subscribe-block-wc-email-rendering branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack add/subscribe-block-wc-email-rendering

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]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

• ✅ Include a description of your PR changes.
  
• ✅ Add a "[Status]" label (In Progress, Needs Review, ...).
  
• 🔴 Add a "[Type]" label (Bug, Enhancement, Janitorial, Task).
  
• ✅ Add testing instructions.
  
• ✅ Specify whether this PR includes any changes to data or privacy.
  
• ✅ Add changelog entries to affected projects
  

This comment will be updated as you work on your PR and make changes. If you think that some of those checks are not needed for your PR, please explain why you think so. Thanks for cooperation 🤖

---

Follow this PR Review Process:

1. Ensure all required checks appearing at the bottom of this PR are passing.
2. Make sure to test your changes on all platforms that it applies to. You're responsible for the quality of the code you ship.
3. You can use GitHub's Reviewers functionality to request a review.
4. When it's reviewed and merged, you will be pinged in Slack to deploy the changes to WordPress.com simple once the build is done.

If you have questions about anything, reach out in #jetpack-developers for guidance!

---

Jetpack plugin:

No scheduled milestone found for this plugin.

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.

[jp-launch-control]

Code Coverage Summary

Coverage changed in 2 files.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/jetpack/extensions/blocks/button/button.php	18/204 (8.82%)	8.82%	27 💔
projects/plugins/jetpack/extensions/blocks/subscriptions/subscriptions.php	122/678 (17.99%)	3.53%	0 💚

Full summary · PHP report · JS report

_{Coverage check overridden by I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage. .}

[simison]

A couple of thoughts:

• Could the code delegate rendering to jetpack/button block, and then we can use the same email rendering to render buttons for all sorts of things like donations block, payment blocks, paywalls in emails, subscription block, jetpack forms, etc.
• Alternatively, delegate to core/button which we should also support.

[allilevine]

A couple of thoughts:

• Could the code delegate rendering to jetpack/button block, and then we can use the same email rendering to render buttons for all sorts of things like donations block, payment blocks, paywalls in emails, subscription block, jetpack forms, etc.
• Alternatively, delegate to core/button which we should also support.

I'll try it out, thanks for the suggestion! We do support core/button here.

[yuliyan]

The button and jetpack/subscriptions work pretty well overall - nice work! I just noticed a few minor styling issues and left comments on those.