Site Health: get_test_theme_version() + WP_DEFAULT_THEME = use get_core_default_theme() !

[juliobox]

Hello there

The test for get_test_theme_version() is checking if WP_DEFAULT_THEME is set to one of our installed theme. If not, the SH will tell us to use one.
But since I have a twentystuff theme on my installation, WordPress will find a fallback. Thanks to get_core_default_theme()!

We should also use this as a check.
I just did this:

<?php
if ( ! $has_default_theme ) {

becomes:

<?php
if ( ! $has_default_theme && ! WP_Theme::get_core_default_theme() ) {

That does the correct test I guess.

Thank you!

[SergeyBiryukov]

Makes sense to me, populate_options() and validate_current_theme() do the same.

[ajayghaghretiya1]

updated the file with the patch, Also check class exist.

[desrosj]

Moving Site Health tickets into their lovely new home, the Site Health component.

[SergeyBiryukov]

In 45732:

Site Health: If WP_DEFAULT_THEME doesn't exist, use WP_Theme::get_core_default_theme() as a fallback.

Props ajayghaghretiya1, juliobox, SergeyBiryukov.
Fixes #47299.