Show the correct homepage when previewing a theme in the Site Editor

[okmttdhr]

Proposed changes:

Show the correct homepage when previewing a theme in the Site Editor to support Block Theme Previews on dotcom. This is done by overriding the show_on_front option to posts.

I added changes in Jetpack jetpack-mu-wpcom since dotcom wants to support Block Theme Previews both on Simple and Atomic sites.

This PR is part of Automattic/wp-calypso#79221.

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?

No

Testing instructions:

Atomic sites

• Create an Atomic site
• Change your Reading Settings to show a static page as a homepage
• Patch this PR to your site by following Show the correct homepage when previewing a theme in the Site Editor #31929 (comment)
  • Note that you must set define( 'JETPACK_MU_WPCOM_LOAD_VIA_BETA_PLUGIN', true ); to your wp-config.php
• Install a theme
• Go to Block Theme Previews with /wp-admin/site-editor.php?wp_theme_preview=<your-theme> (e.g. ?wp_theme_preview=pendant)
• Verify Block Theme Previews show Index or Home template as a homepage

Simple sites

• Create a site
• Change your Reading Settings to show a static page as a homepage
• Patch this PR to your sandbox by following Show the correct homepage when previewing a theme in the Site Editor #31929 (comment)
• Sandbox your testing site AND public-api.wordpress.com
• Go to Block Theme Previews with /wp-admin/site-editor.php?wp_theme_preview=<your-theme> (e.g. ?wp_theme_preview=pub/pendant)
• Verify Block Theme Previews show Index or Home template as a homepage

self-hosted site

• Patch this PR to your site
  • I used jetpack rsync PCYsg-eg0-p2
• Go to Block Theme Previews with /wp-admin/site-editor.php?wp_theme_preview=<your-installed-theme> (e.g. ?wp_theme_preview=twentytwentytwo)
• Verify nothing breaks on the Site Editor

[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 WordPress.com Simple 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 > Jetpack and enable the add/site-editor-homepage branch.

• To test on Simple, run the following command on your sandbox:

  bin/jetpack-downloader test jetpack-mu-wpcom-plugin add/site-editor-homepage
  

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.
  
• ✅ All commits were linted before commit.
  
• ✅ Add a "[Status]" label (In Progress, Needs Team Review, ...).
  
• ✅ 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 🤖

---

The e2e test report can be found here. Please note that it can take a few minutes after the e2e tests checks are complete for the report to be available.

---

Once your PR is ready for review, check one last time that all required checks (other than "Required review") appearing at the bottom of this PR are passing or skipped.
Then, add the "[Status] Needs Team Review" label and ask someone from your team review the code. Once reviewed, it can then be merged.
If you need an extra review from someone familiar with the codebase, you can update the labels from "[Status] Needs Team Review" to "[Status] Needs Review", and in that case Jetpack Approvers will do a final review of your PR.

---

Jetpack plugin:

• Next scheduled release: August 1, 2023.
• Scheduled code freeze: July 24, 2023.

---

Mu Wpcom plugin:

• Next scheduled release: August 1, 2023.
• Scheduled code freeze: July 24, 2023.

[taipeicoder]

Testes:

Atomic sites: ✅ BTP shows Index of Home template as homepage.
Simple sites: ✅ BTP works as before.
Self-hosted sites: ✅ BTP works as before.

[jeherve]

I'm not sure I fully understand why this is in Jetpack. I think I'm missing some context on this, probably.

If we always want to show the posts page when previewing a new theme, shouldn't we make that change in Core directly, since theme previews will soon be available to everyone?

[arthur791004]

@jeherve Based on pekYwv-1BS-p2 and pekYwv-1BS-p2#comment-1187, I guess Core won't touch the reading settings in the short term since Core won't change the reading settings during the theme switch. So, it makes sense to keep the current reading settings when you're previewing a theme in the site editor on Core.

However, dotcom has a mechanism to update the reading settings based on the headstart annotation of the theme. So, we have to override the show_on_front option dynamically on both simple and atomic sites to make the preview look the same after the theme switch. That's why we made the change on Jetpack.

Does it make sense? Or any thoughts?

[jeherve]

Ok, that makes sense. In this situation, and since this is really only interesting for WordPress.com sites (simple and WoA), maybe this should be shipped in the mu-wpcom plugin instead?
https://github.com/Automattic/jetpack/tree/trunk/projects/plugins/mu-wpcom-plugin

[arthur791004]

👍

[okmttdhr]

@Automattic/lego I requested your reviews again as I resolved conflicts 🙏 Thank you!

[fushar]

Tested by using the following scenarios:

• current theme: Appleton, which has a static homepage set.
• previewing theme: Pendant, which has the Home template.

Atomic site ✅

Before	After

Simple site ❌

Before	After

I am not sure what I'm doing wrong. I have sandboxed my site (see the "Sandboxed" badge at the left-corner of the right screenshot). Log:

$ bin/jetpack-downloader test jetpack-mu-wpcom-plugin add/site-editor-homepage
Current checkout is switch-theme-logic-new. Check out trunk? [Y/n] Y

Updating trunk...
# Request received by "phabricator-b06-29.dfw.automattic.com", forwarding to cluster host "phabricator-b12-10.dfw.automattic.com".
# Acquiring read lock for repository "wpcom-git" on device "phabricator-b12-10.dfw.automattic.com"...
# Acquired read lock immediately.
# Device "phabricator-b12-10.dfw.automattic.com" is already a cluster leader and does not need to be synchronized.
# Cleared to fetch on cluster host "phabricator-b12-10.dfw.automattic.com".

Updating files:  53% (12198/23014)
Updating files:  61% (14039/23014)
Updating files: 100% (23014/23014), done.
Determining jetpack-mu-wpcom-plugin download URL...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 10406  100 10406    0     0  47733      0 --:--:-- --:--:-- --:--:-- 47733
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  8181  100  8181    0     0  71763      0 --:--:-- --:--:-- --:--:-- 72398
Downloading jetpack-mu-wpcom-plugin...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 80835  100 80835    0     0   400k      0 --:--:-- --:--:-- --:--:--  398k
Unpacking jetpack-mu-wpcom-plugin...
jetpack-mu-wpcom-plugin add/site-editor-homepage is now checked out in sun!
If you intend to commit it, use `git add -Af wp-content/mu-plugins/jetpack-mu-wpcom-plugin/sun` to ensure all files are added.
To reset your environment instead, use `jetpack-downloader reset jetpack-mu-wpcom-plugin`.

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Will test on a JN site soon.

[okmttdhr]

I am not sure what I'm doing wrong. I have sandboxed my site (see the "Sandboxed" badge at the left-corner of the right screenshot).

This is weird. 👀 I will check it Monday!
One thing I want to confirm is if you sandboxed public-api.wordpress.com as well. @fushar

[fushar]

Will test on a JN site soon.

Jetpack-connected self-hosted site ✅

Nothing breaks!

[taipeicoder]

Gave a test on Simple Sites, and it works as expected 👍

[fushar]

Update:

Simple site ✅

Before	After

Needed to change .config/jetpack-loader.php from moon to sun.