Changeset 61981

Timestamp:

03/12/2026 05:44:22 AM (2 months ago)

Author:

westonruter

Message:

Script Loader: Move wp_load_classic_theme_block_styles_on_demand() from init to wp_default_styles.

This ensures the filters to opt in to loading separate block styles on demand are added at the moment WP_Styles is constructed. This accounts for styles being registered at the init action before register_core_block_style_handles() runs at priority 9. Without this, the wp-block-library stylesheet may get registered with the full combined block styles as style.css instead of just common.css, due to wp_should_load_block_assets_on_demand() still returning false. The wp_default_styles action still runs during init.

Developed in ​https://github.com/WordPress/wordpress-develop/pull/11232

Follow-up to r61008.

Props westonruter, adamsilverstein.
See #64099.
Fixes #64846.

Location:

trunk

Files:

• src/wp-includes/default-filters.php (modified) (1 diff)
• src/wp-includes/script-loader.php (modified) (1 diff)
• tests/phpunit/tests/template.php (modified) (2 diffs)

trunk/src/wp-includes/default-filters.php

@@ -608 +608 @@
 add_action( 'enqueue_block_assets', 'wp_enqueue_registered_block_scripts_and_styles' );
 add_action( 'enqueue_block_assets', 'enqueue_block_styles_assets', 30 );
-add_action( 'init', 'wp_load_classic_theme_block_styles_on_demand', 8 ); // Must happen before register_core_block_style_handles() at priority 9.
+add_action( 'wp_default_styles', 'wp_load_classic_theme_block_styles_on_demand', 0 ); // Must happen before wp_default_styles() and register_core_block_style_handles().
 /*
  * `wp_enqueue_registered_block_scripts_and_styles` is bound to both

trunk/src/wp-includes/script-loader.php

@@ -3675 +3675 @@
  * Adds hooks to load block styles on demand in classic themes.
  *
+ * This function must be called before {@see wp_default_styles()} and {@see register_core_block_style_handles()} so that
+ * the filters are added to cause {@see wp_should_load_separate_core_block_assets()} to return true.
+ *
  * @since 6.9.0
+ * @since 7.0.0 This is now invoked at the `wp_default_styles` action with priority 0 instead of at `init` with priority 8.
  *
  * @see _add_default_theme_supports()
  */
-function wp_load_classic_theme_block_styles_on_demand() {
+function wp_load_classic_theme_block_styles_on_demand(): void {
     // This is not relevant to block themes, as they are opted in to loading separate styles on demand via _add_default_theme_supports().
     if ( wp_is_block_theme() ) {

trunk/tests/phpunit/tests/template.php

@@ -1964 +1964 @@
         self::touch( ABSPATH . WPINC . '/js/wp-emoji-loader.js' );
 
+        if ( $set_up ) {
+            $set_up();
+        }
+
         switch_theme( 'default' );
         global $wp_styles;
@@ -2001 +2005 @@
             }
         );
-
-        if ( $set_up ) {
-            $set_up();
-        }
 
         wp_load_classic_theme_block_styles_on_demand();