Script Loader: Resolve the global script modules instance in hook callbacks

src/wp-includes/class-wp-script-modules.php

@@ -433,7 +433,7 @@ public function print_script_module_translations(): void {
 	public function add_hooks() {
 		$is_block_theme = wp_is_block_theme();
 		$position       = $is_block_theme ? 'wp_head' : 'wp_footer';
-		add_action( $position, array( $this, 'print_import_map' ) );
+		add_action( $position, 'wp_print_script_module_import_map' );
 		if ( $is_block_theme ) {
 			/*
 			 * Modules can only be printed in the head for block themes because only with
@@ -442,28 +442,28 @@ public function add_hooks() {
 			 * template rendering, thus the import map must be printed in the footer,
 			 * followed by all enqueued modules.
 			 */
-			add_action( 'wp_head', array( $this, 'print_head_enqueued_script_modules' ) );
+			add_action( 'wp_head', 'wp_print_head_script_modules' );
 		}
-		add_action( 'wp_footer', array( $this, 'print_enqueued_script_modules' ) );
-		add_action( $position, array( $this, 'print_script_module_preloads' ) );
+		add_action( 'wp_footer', 'wp_print_script_modules' );
+		add_action( $position, 'wp_print_script_module_preloads' );
 
-		add_action( 'admin_print_footer_scripts', array( $this, 'print_import_map' ), 9 );
-		add_action( 'admin_print_footer_scripts', array( $this, 'print_enqueued_script_modules' ) );
-		add_action( 'admin_print_footer_scripts', array( $this, 'print_script_module_preloads' ) );
+		add_action( 'admin_print_footer_scripts', 'wp_print_script_module_import_map', 9 );
+		add_action( 'admin_print_footer_scripts', 'wp_print_script_modules' );
+		add_action( 'admin_print_footer_scripts', 'wp_print_script_module_preloads' );
 
 		/*
 		 * Print translations after classic scripts like wp-i18n are loaded (at
 		 * priority 10 via _wp_footer_scripts), but before the script modules
 		 * execute. Script modules with type="module" are deferred by default,
 		 * so inline translation scripts at priority 11 will execute before them.
 		 */
-		add_action( 'wp_footer', array( $this, 'print_script_module_translations' ), 21 );
-		add_action( 'admin_print_footer_scripts', array( $this, 'print_script_module_translations' ), 11 );
+		add_action( 'wp_footer', 'wp_print_script_module_translations', 21 );
+		add_action( 'admin_print_footer_scripts', 'wp_print_script_module_translations', 11 );
 
-		add_action( 'wp_footer', array( $this, 'print_script_module_data' ) );
-		add_action( 'admin_print_footer_scripts', array( $this, 'print_script_module_data' ) );
-		add_action( 'wp_footer', array( $this, 'print_a11y_script_module_html' ), 20 );
-		add_action( 'admin_print_footer_scripts', array( $this, 'print_a11y_script_module_html' ), 20 );
+		add_action( 'wp_footer', 'wp_print_script_module_data' );
+		add_action( 'admin_print_footer_scripts', 'wp_print_script_module_data' );
+		add_action( 'wp_footer', 'wp_print_a11y_script_module_html', 20 );
+		add_action( 'admin_print_footer_scripts', 'wp_print_a11y_script_module_html', 20 );
 	}
 
 	/**

src/wp-includes/script-modules.php

@@ -159,6 +159,83 @@ function wp_set_script_module_translations( string $id, string $domain = 'defaul
 	return wp_script_modules()->set_translations( $id, $domain, $path );
 }
 
+/**
+ * Prints the import map using a script tag with a type="importmap" attribute.
+ *
+ * @since 7.2.0
+ *
+ * @see WP_Script_Modules::print_import_map()
+ */
+function wp_print_script_module_import_map(): void {
+	wp_script_modules()->print_import_map();
+}
+
+/**
+ * Prints the enqueued script modules in head.
+ *
+ * @since 7.2.0
+ *
+ * @see WP_Script_Modules::print_head_enqueued_script_modules()
+ */
+function wp_print_head_script_modules(): void {
+	wp_script_modules()->print_head_enqueued_script_modules();
+}
+
+/**
+ * Prints the enqueued script modules in footer.
+ *
+ * @since 7.2.0
+ *
+ * @see WP_Script_Modules::print_enqueued_script_modules()
+ */
+function wp_print_script_modules(): void {
+	wp_script_modules()->print_enqueued_script_modules();
+}
+
+/**
+ * Prints the static dependencies of the enqueued script modules using link tags with rel="modulepreload" attributes.
+ *
+ * @since 7.2.0
+ *
+ * @see WP_Script_Modules::print_script_module_preloads()
+ */
+function wp_print_script_module_preloads(): void {
+	wp_script_modules()->print_script_module_preloads();
+}
+
+/**
+ * Prints the translations of the script modules that will be printed on the page.
+ *
+ * @since 7.2.0
+ *
+ * @see WP_Script_Modules::print_script_module_translations()
+ */
+function wp_print_script_module_translations(): void {
+	wp_script_modules()->print_script_module_translations();
+}
+
+/**
+ * Prints the data associated with the script modules that will be printed on the page.
+ *
+ * @since 7.2.0
+ *
+ * @see WP_Script_Modules::print_script_module_data()
+ */
+function wp_print_script_module_data(): void {
+	wp_script_modules()->print_script_module_data();
+}
+
+/**
+ * Prints the HTML regions used by the `@wordpress/a11y` script module.
+ *
+ * @since 7.2.0
+ *
+ * @see WP_Script_Modules::print_a11y_script_module_html()
+ */
+function wp_print_a11y_script_module_html(): void {
+	wp_script_modules()->print_a11y_script_module_html();
+}
+
 /**
  * Registers all the default WordPress Script Modules.
  *

tests/phpunit/tests/script-modules/wpScriptModules.php

@@ -2924,4 +2924,35 @@ static function ( $translations, $file, $handle, $domain ) use ( &$seen_domain )
 		$this->assertSame( 'my-plugin', $seen_domain, 'load_script_module_textdomain() should be called with the overridden domain.' );
 		$this->assertStringContainsString( 'Hola', $output, 'Output should contain the translated string loaded under the overridden domain.' );
 	}
+
+	/**
+	 * Tests that the hooks added by add_hooks() print the script modules of the
+	 * current global instance, not the instance that added the hooks.
+	 *
+	 * @ticket 66100
+	 * @covers WP_Script_Modules::add_hooks
+	 */
+	public function test_add_hooks_callbacks_use_the_current_global_instance() {
+		global $wp_script_modules;
+
+		// Add the hooks the way wp-settings.php does, with the instance that is the global at that moment.
+		wp_script_modules()->add_hooks();
+
+		// Replace the global instance after the hooks have been added.
+		$wp_script_modules = new WP_Script_Modules();
+
+		wp_enqueue_script_module( 'test-hooks-global', '/test-hooks-global.js' );
+
+		$output = get_echo(
+			static function () {
+				do_action( 'admin_print_footer_scripts' );
+			}
+		);
+
+		$this->assertStringContainsString(
+			'test-hooks-global',
+			$output,
+			'The print callbacks added by add_hooks() must read the current global WP_Script_Modules instance.'
+		);
+	}
 }