Changeset 61466

Timestamp:

01/10/2026 06:28:18 PM (8 months ago)

Author:

westonruter

Message:

Widgets: Ensure a widget is registered prior to checking its ID in is_active_widget().

This avoids a possible PHP warning due to an undefined array key.

Developed in ​https://github.com/WordPress/wordpress-develop/pull/10710

Follow-up to [11090], [7080].

Props sageth, josephscott, Ipstenu, mindctrl, westonruter.
See #8441, #6023.
Fixes #57518.

Location:

trunk

Files:

• src/wp-includes/widgets.php (modified) (1 diff)
• tests/phpunit/tests/widgets.php (modified) (1 diff)
• tests/phpunit/tests/widgets/wpBlockThemeRegisterClassicSidebar.php (modified) (2 diffs)

trunk/src/wp-includes/widgets.php

@@ -926 +926 @@
                                 foreach ( $widgets as $widget ) {
                                         if ( ( $callback && isset( $wp_registered_widgets[ $widget ]['callback'] ) && $wp_registered_widgets[ $widget ]['callback'] === $callback ) || ( $id_base && _get_widget_id_base( $widget ) === $id_base ) ) {
-                                                if ( ! $widget_id || $widget_id === $wp_registered_widgets[ $widget ]['id'] ) {
+                                                if ( ! $widget_id || ( isset( $wp_registered_widgets[ $widget ]['id'] ) && $widget_id === $wp_registered_widgets[ $widget ]['id'] ) ) {
                                                         return $sidebar;
                                                 }

trunk/tests/phpunit/tests/widgets.php

@@ -1413 +1413 @@
                 $this->assertSame( array(), $new_sidebars['primary'], 'Primary sidebar should be an empty array after normalization.' );
         }
+
+        /**
+         * Tests that is_active_widget() does not generate a PHP warning when
+         * a widget ID exists in sidebars_widgets but is not in $wp_registered_widgets,
+         * and the function is called with id_base and widget_id parameters.
+         *
+         * This can happen when a widget is saved to a sidebar but the widget class
+         * has not yet been registered (e.g., during early plugin/theme loading).
+         *
+         * @ticket 57518
+         * @covers ::is_active_widget
+         */
+        public function test_is_active_widget_with_unregistered_widget_and_id_base_match() {
+                global $wp_registered_widgets;
+
+                // Set up a sidebar with a widget that is NOT registered in $wp_registered_widgets.
+                update_option(
+                        'sidebars_widgets',
+                        array(
+                                'wp_inactive_widgets' => array(),
+                                'sidebar-1'           => array( 'search-2' ),
+                                'array_version'       => 3,
+                        )
+                );
+
+                // Ensure the widget is NOT in $wp_registered_widgets.
+                unset( $wp_registered_widgets['search-2'] );
+
+                /*
+                 * Call is_active_widget() with id_base and widget_id parameters.
+                 * This should NOT generate a PHP warning about accessing array offset on null.
+                 *
+                 * The bug occurs because when matching by id_base, the code checks
+                 * _get_widget_id_base( $widget ) === $id_base without verifying
+                 * $wp_registered_widgets[ $widget ] exists, then tries to access
+                 * $wp_registered_widgets[ $widget ]['id'] on the next line.
+                 */
+                $result = is_active_widget( false, 'search-2', 'search', true );
+
+                $this->assertFalse( $result, 'The widget is not registered, so the function should return false.' );
+        }
 }

trunk/tests/phpunit/tests/widgets/wpBlockThemeRegisterClassicSidebar.php

@@ -33 +33 @@
                 global $wp_registered_sidebars;
 
+                // Register a sidebar for testing if none exist.
+                if ( empty( $wp_registered_sidebars ) ) {
+                        register_sidebar( array( 'id' => 'test-sidebar' ) );
+                }
+
                 $sidebar_id = array_key_first( $wp_registered_sidebars );
                 $this->assertNotEmpty( $sidebar_id );
@@ -42 +47 @@
         public function test_should_reregister_previous_theme_sidebar() {
                 global $wp_registered_sidebars;
+
+                // Register a sidebar for testing if none exist.
+                if ( empty( $wp_registered_sidebars ) ) {
+                        register_sidebar( array( 'id' => 'test-sidebar' ) );
+                }
 
                 $sidebar_id = array_key_first( $wp_registered_sidebars );