Ticket #64376: 64376.diff

wp-includes/canonical.php

@@ -445 +445 @@
                 $redirect['path'] = $redirect_obj->path;
 
         // Attachment (non-empty attachment_id, no attachment slug, & no other query vars).
-        } elseif ( is_attachment()
-                && ! array_diff( array_keys( $wp->query_vars ), array( 'attachment', 'attachment_id' ) )
-                && ! $redirect_url
-        ) {
-                $redirect_url = get_attachment_link( get_query_var( 'attachment_id' ) );
-                $redirect_obj = get_post( get_query_var( 'attachment_id' ) );
+        } elseif ( is_attachment()
+                && ! array_diff( array_keys( $wp->query_vars ), array( 'attachment', 'attachment_id' ) )
+                && ! $redirect_url
+        ) {
+
+                // Existing WordPress canonical behavior.
+                $redirect_url = get_attachment_link( get_query_var( 'attachment_id' ) );
+                $redirect_obj = get_post( get_query_var( 'attachment_id' ) );
+
+                /**
+                 * NEW: Redirect old media URLs to the new plain-name permalink structure.
+                 *
+                 * OLD:
+                 *   /?attachment_id=123
+                 *   /uploads/2023/10/photo.jpg
+                 *
+                 * NEW:
+                 *   /photo/
+                 */
+                if ( $redirect_obj && 'attachment' === $redirect_obj->post_type ) {
+
+                        // Build clean permalink based on post_name.
+                        $new_structure_url = home_url( '/' . $redirect_obj->post_name . '/' );
+
+                        // Apply redirect only if URL differs from current permalink.
+                        if ( $new_structure_url !== $redirect_url ) {
+                                $redirect_url = $new_structure_url;
+                        }
+                }
+
+                if ( $redirect_url ) {
+                        $redirect['query'] = remove_query_arg( 'attachment_id', $redirect['query'] );
+                }
         }