Changeset 65317 for trunk/src/wp-includes/class-wp-theme.php

Timestamp:

11/06/2026 07:34:18 PM (3 days ago)

Author:

SergeyBiryukov

Message:

Code Modernization: Simplify isset() guards that initialize empty arrays.

Covering one recognizable idiom: initializing a container to an empty array before writing into it.

-if ( ! isset( $widget_options[ $widget_id ] ) ) {
-       $widget_options[ $widget_id ] = array();
-}
+$widget_options[ $widget_id ] ??= array();

Every one of the 54 changed guards is an isset() check whose entire body is a single = array(); assignment to the tested expression. Each one is handled by one of four rules, so no case needs individual judgement:

1. Convert the guard to ??= (35 places).
2. Collapse nested guard chains to the deepest key, since ??= autovivifies missing parent arrays (add_meta_box(), remove_meta_box()):

   $wp_meta_boxes[ $page ][ $context ] ??= array();
   

3. Remove the guard where the next statement writes into the same array or property anyway, since that write creates it (9 places):

   -if ( ! isset( $object_terms[ $id ] ) ) {
   -       $object_terms[ $id ] = array();
   -}
    $object_terms[ $id ][ $taxonomy ] = array();
   

4. Inline the default where the next statement reassigns the same expression from an array_merge() call (3 places):

   $this->headers[ $key ] = array_merge( $this->headers[ $key ] ?? array(), $value );
   

Why this is safe

• ??= requires PHP 7.4, which is already the minimum supported version.
• ??=, ?? and ! isset() test the same condition, so the default is used in exactly the same cases.
• Only blocks whose body is a single assignment were changed. Any guard containing further statements was skipped, since ??= would let those statements run unconditionally.
• Removed guards are only those directly followed by a write into the same array, or into a property of a stdClass object, where PHP creates the missing container the same way.
• No behavior change.

Developed in ​https://github.com/WordPress/wordpress-develop/pull/12912.

Props Soean, mukesh27, westonruter.
See #65823.

File:

• trunk/src/wp-includes/class-wp-theme.php (modified) (1 diff)

trunk/src/wp-includes/class-wp-theme.php

@@ -1395 +1395 @@
 
                                 foreach ( $types as $type ) {
-                                        $type = sanitize_key( $type );
-                                        if ( ! isset( $post_templates[ $type ] ) ) {
-                                                $post_templates[ $type ] = array();
-                                        }
+                                        $type                      = sanitize_key( $type );
+                                        $post_templates[ $type ] ??= array();
 
                                         $post_templates[ $type ][ $file ] = $headers['TemplateName'];