[Theme compatibility] WP/PHP compatibility tests for multisite updates

[afragen]

As part of #48491, this ticket is to monitor multisite theme updating. This ticket and patches assume #48491 committed.

If a theme is not compatible with the currently running WP or PHP version, updating will be blocked for multisite.

[afragen]

Yes, I changed values while running to demonstrate the incompatibility.

[afragen]

Pinging @jorbin per our discussion at WCPHX.

[afragen]

updated

[afragen]

Updated to cleanly apply patch.

[Clorith]

Moving this to the 5.5 milestone, as it's marked early, and we are one day away from beta for 5.4

[davidbaumwald]

With 5.5 Beta 1 approaching, the time for early tickets has now passed, and this ticket is being moved to Future Release. If any maintainer or committer feels this can be quickly resolved for 5.5 or wishes to assume ownership of this ticket during a specific cycle, feel free to update the milestone accordingly.

[afragen]

I think this can be easily reviewed and tested. As it is one part of the already committed tickets regarding theme WP/PHP compatibility, I think it really needs to be considered for 5.5.

Pinging @SergeyBiryukov

[melchoyce]

We talked about this in ​today's #design triage.

Can the second line of text be indented to match the first line of text?

Also, the copy sounds pretty technical, and doesn't have an explicit action attached to help people figure out how to fix the issue. Are we able to tell what doesn't match — either the WordPress version, or the PHP version, or both? That can help us write some text that helps people figure out what to do next.

[SergeyBiryukov]

In 48660:

Themes: Display a message on Themes list table if a theme update requires a higher version of PHP or WordPress.

This applies to the Themes screen in Multisite network admin.

Props afragen, SergeyBiryukov.
Fixes #48507. See #48491.

[pbiron]

In 5.5-RC1 I'm getting a Undefined variable: compatible_php warning.

48507.3.diff​ corrects this by passing the correct param to is_php_version_compatible().

[afragen]

@pbiron's above issue should be fixed by his patch.

[SergeyBiryukov]

In 48689:

Themes: Pass correct variable to is_php_version_compatible() in wp_theme_update_row().

This applies to the Themes screen in Multisite network admin.

Follow-up to [48660].

Props pbiron, afragen.
Fixes #48507. See #48491.

[SergeyBiryukov]

Reopening for backporting to the 5.5 branch after a second committer's review.

[peterwilsoncc]

@SergeyBiryukov [48689] reviewed for backporting to 5.5, variable renamed correctly ✅

[SergeyBiryukov]

In 48690:

Themes: Pass correct variable to is_php_version_compatible() in wp_theme_update_row().

This applies to the Themes screen in Multisite network admin.

Follow-up to [48660].

Props pbiron, afragen.
Reviewed by peterwilsoncc, SergeyBiryukov.
Merges [48689] to the 5.5 branch.
Fixes #48507. See #48491.

[justinahinon]

Dev note link: ​https://make.wordpress.org/core/2020/07/30/themes-field-guide-wordpress-5-5/