Ticket #27177: 27177.diff

src/wp-includes/default-filters.php

@@ -215 +215 @@
 add_action( 'wp_print_footer_scripts', '_wp_footer_scripts'                 );
 add_action( 'init',                'check_theme_switched',            99    );
 add_action( 'after_switch_theme',  '_wp_sidebars_changed'                   );
+add_action( 'after_switch_theme',  '_maybe_inherit_theme_mods',       10, 2 );
 
 if ( isset( $_GET['replytocom'] ) )
     add_action( 'wp_head', 'wp_no_robots' );

src/wp-includes/theme.php

@@ -1891 +1891 @@
 }
 
 /**
+ * Updates the new theme with the theme mods of the old theme.
+ *
+ * @param string   $template Old theme name.
+ * @param WP_Theme $theme    WP_Theme instance of the old theme.
+ */
+function _maybe_inherit_theme_mods( $template, $theme = null ) {
+        // If the old theme exists, $template is the theme name.
+        if ( $template_exists = is_a( $theme, 'WP_Theme' ) ) {
+                $template = $theme->get_stylesheet();
+        }
+
+        // If the old theme is the new themes parent...
+        if ( wp_get_theme()->get_template() === $template ) {
+
+                // Check legacy theme mods if the old theme exists.
+                if ( false === ( $mods = get_option( "theme_mods_$template" ) ) && $template_exists ) {
+                        $theme_name = $theme->get( 'Name' );
+                        $mods = get_option( "mods_$theme_name" ); // Deprecated location.
+                }
+
+                // ...and it has theme mods, pass them on.
+                if ( false !== $mods ) {
+                        foreach ( (array) $mods as $name => $value ) {
+                                if ( 'sidebars_widgets' == $name ) {
+                                        continue;
+                                }
+                                set_theme_mod( $name, $value );
+                        }
+                }
+        }
+}
+
+/**
  * Includes and instantiates the WP_Customize_Manager class.
  *
  * Fires when ?wp_customize=on or on wp-admin/customize.php.