Changeset 55950

Timestamp:

06/20/2023 05:52:32 PM (11 months ago)

Author:

flixos90

Message:

Editor: Introduce WP_Theme_JSON::prepend_to_selector() to improve code quality and performance.

The WP_Theme_JSON::append_to_selector() method was previously used for both appending and prepending which violated the single responsibility principle. It resulted in additional conditionals which also came at a performance cost, particularly because the method is called over 1,000 times during a regular WordPress request.

With the new WP_Theme_JSON::prepend_to_selector() method, there are now two distinct methods for the two distinct purposes. The now useless third parameter on WP_Theme_JSON::append_to_selector() has been removed (rather than deprecated), which is acceptable given that it is a protected method on a class that is not intended for extensions.

Props bor0, costdev, flixos90, isabel_brison, oandregal, spacedmonkey.
Fixes #58193.
See #58457.

File:

• trunk/src/wp-includes/class-wp-theme-json.php (modified) (3 diffs)

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

@@ -796 +796 @@
      * @since 5.8.0
      * @since 6.1.0 Added append position.
+     * @since 6.3.0 Removed append position parameter.
      *
      * @param string $selector  Original selector.
      * @param string $to_append Selector to append.
-     * @param string $position  A position sub-selector should be appended. Default 'right'.
      * @return string The new selector.
      */
-    protected static function append_to_selector( $selector, $to_append, $position = 'right' ) {
+    protected static function append_to_selector( $selector, $to_append ) {
         if ( ! str_contains( $selector, ',' ) ) {
-            return 'right' === $position ? $selector . $to_append : $to_append . $selector;
+            return $selector . $to_append;
         }
         $new_selectors = array();
         $selectors     = explode( ',', $selector );
         foreach ( $selectors as $sel ) {
-            $new_selectors[] = 'right' === $position ? $sel . $to_append : $to_append . $sel;
+            $new_selectors[] = $sel . $to_append;
+        }
+        return implode( ',', $new_selectors );
+    }
+
+    /**
+     * Prepends a sub-selector to an existing one.
+     *
+     * Given the compounded $selector "h1, h2, h3"
+     * and the $to_prepend selector ".some-class " the result will be
+     * ".some-class h1, .some-class  h2, .some-class  h3".
+     *
+     * @since 6.3.0
+     *
+     * @param string $selector   Original selector.
+     * @param string $to_prepend Selector to prepend.
+     * @return string The new selector.
+     */
+    protected static function prepend_to_selector( $selector, $to_prepend ) {
+        if ( ! str_contains( $selector, ',' ) ) {
+            return $to_prepend . $selector;
+        }
+        $new_selectors = array();
+        $selectors     = explode( ',', $selector );
+        foreach ( $selectors as $sel ) {
+            $new_selectors[] = $to_prepend . $sel;
         }
         return implode( ',', $new_selectors );
@@ -901 +926 @@
                         break;
                     }
-                    $element_selector[] = static::append_to_selector( $el_selector, $selector . ' ', 'left' );
+                    $element_selector[] = static::prepend_to_selector( $el_selector, $selector . ' ' );
                 }
                 static::$blocks_metadata[ $block_name ]['elements'][ $el_name ] = implode( ',', $element_selector );
@@ -1538 +1563 @@
             foreach ( $preset_metadata['classes'] as $class => $property ) {
                 foreach ( $slugs as $slug ) {
-                    $css_var     = static::replace_slug_in_string( $preset_metadata['css_vars'], $slug );
-                    $class_name  = static::replace_slug_in_string( $class, $slug );
-                    $stylesheet .= static::to_ruleset(
-                        static::append_to_selector( $selector, $class_name ),
+                    $css_var    = static::replace_slug_in_string( $preset_metadata['css_vars'], $slug );
+                    $class_name = static::replace_slug_in_string( $class, $slug );
+
+                    // $selector is often empty, so we can save ourselves the `append_to_selector()` call then.
+                    $new_selector = '' === $selector ? $class_name : static::append_to_selector( $selector, $class_name );
+                    $stylesheet  .= static::to_ruleset(
+                        $new_selector,
                         array(
                             array(