Changeset 62698 for trunk/src/wp-includes/media.php

Timestamp:

07/12/2026 09:04:58 PM (2 months ago)

Author:

joedolson

Message:

Media: Ensure figcaption/figure IDs are unique.

Using the same image multiple times with a figure and fig caption would result in duplicate IDs, creating unclear relationships and breaking 3rd party expectations for anchor targets. Check id attributes and append a counter to ensure each attribute is unique, while retaining the current expectation of a counter-less ID attribute for the first instance. Update tests to verify.

Developed in ​https://github.com/WordPress/wordpress-develop/pull/11940

Props steelwagstaff, westonruter, jamesbregenzer, joedolson, mukesh27.
Fixes #65315.

File:

• trunk/src/wp-includes/media.php (modified) (2 diffs)

trunk/src/wp-includes/media.php

@@ -2657 +2657 @@
         }
 
+        /**
+         * @var array{
+         *     id: string,
+         *     caption_id: string,
+         *     align: string,
+         *     width: string,
+         *     caption: string,
+         *     class: string,
+         * } $atts
+         */
         $atts = shortcode_atts(
                 array(
@@ -2676 +2686 @@
         }
 
-        $id          = '';
-        $caption_id  = '';
-        $describedby = '';
+        $id               = '';
+        $caption_id       = '';
+        $describedby      = '';
+        $unique_id_value  = '';
+        $caption_id_value = '';
 
         if ( $atts['id'] ) {
-                $atts['id'] = sanitize_html_class( $atts['id'] );
-                $id         = 'id="' . esc_attr( $atts['id'] ) . '" ';
+                $atts['id']      = sanitize_html_class( $atts['id'] );
+                $unique_id_value = (string) preg_replace( '/-1$/', '', wp_unique_prefixed_id( $atts['id'] . '-' ) );
+                $id              = 'id="' . esc_attr( $unique_id_value ) . '" ';
         }
 
         if ( $atts['caption_id'] ) {
+                // User explicitly provided a caption_id - make it unique.
                 $atts['caption_id'] = sanitize_html_class( $atts['caption_id'] );
-        } elseif ( $atts['id'] ) {
-                $atts['caption_id'] = 'caption-' . str_replace( '_', '-', $atts['id'] );
-        }
-
-        if ( $atts['caption_id'] ) {
-                $caption_id  = 'id="' . esc_attr( $atts['caption_id'] ) . '" ';
-                $describedby = 'aria-describedby="' . esc_attr( $atts['caption_id'] ) . '" ';
+                $caption_id_value   = preg_replace( '/-1$/', '', wp_unique_prefixed_id( $atts['caption_id'] . '-' ) );
+        } elseif ( $unique_id_value ) {
+                // Derive from the already-unique figure ID - guaranteed unique, no need for second call.
+                $caption_id_value = 'caption-' . str_replace( '_', '-', $unique_id_value );
+        }
+
+        if ( $caption_id_value ) {
+                $caption_id  = 'id="' . esc_attr( $caption_id_value ) . '" ';
+                $describedby = 'aria-describedby="' . esc_attr( $caption_id_value ) . '" ';
         }