Customize: Prevent dropping backslashes from input on general settings and settings for nav menus and some widgets.

Ensures that intentional backslashes (e.g. "\o/") can be used in:

* Site title
* Site description
* Nav menu name
* Custom Menu widget title
* Tag Cloud widget title
* Text widget body if can't `unfiltered_html`

The latter three are also fixed on the widgets admin page.

Fixes #35898.


git-svn-id: https://develop.svn.wordpress.org/trunk@36622 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-customize-setting.php

@@ -496,7 +496,6 @@ class WP_Customize_Setting {
 	 * @return string|array|null Null if an input isn't valid, otherwise the sanitized value.
 	 */
 	public function sanitize( $value ) {
-		$value = wp_unslash( $value );
 
 		/**
 		 * Filter a Customize setting value in un-slashed form.

src/wp-includes/customize/class-wp-customize-nav-menu-setting.php

@@ -513,14 +513,14 @@ class WP_Customize_Nav_Menu_Setting extends WP_Customize_Setting {
 			$menu_data['menu-name'] = $value['name'];
 
 			$menu_id = $is_placeholder ? 0 : $this->term_id;
-			$r = wp_update_nav_menu_object( $menu_id, $menu_data );
+			$r = wp_update_nav_menu_object( $menu_id, wp_slash( $menu_data ) );
 			$original_name = $menu_data['menu-name'];
 			$name_conflict_suffix = 1;
 			while ( is_wp_error( $r ) && 'menu_exists' === $r->get_error_code() ) {
 				$name_conflict_suffix += 1;
 				/* translators: 1: original menu name, 2: duplicate count */
 				$menu_data['menu-name'] = sprintf( __( '%1$s (%2$d)' ), $original_name, $name_conflict_suffix );
-				$r = wp_update_nav_menu_object( $menu_id, $menu_data );
+				$r = wp_update_nav_menu_object( $menu_id, wp_slash( $menu_data ) );
 			}
 
 			if ( is_wp_error( $r ) ) {

src/wp-includes/nav-menu.php

@@ -196,12 +196,15 @@ function is_nav_menu_item( $menu_item_id = 0 ) {
 /**
  * Creates a navigation menu.
  *
+ * Note that <code>$menu_name</code> is expected to be pre-slashed.
+ *
  * @since 3.0.0
  *
  * @param string $menu_name Menu name.
  * @return int|WP_Error Menu ID on success, WP_Error object on failure.
  */
 function wp_create_nav_menu( $menu_name ) {
+	// expected_slashed ($menu_name)
 	return wp_update_nav_menu_object( 0, array( 'menu-name' => $menu_name ) );
 }
 
@@ -252,6 +255,8 @@ function wp_delete_nav_menu( $menu ) {
 /**
  * Save the properties of a menu or create a new menu with those properties.
  *
+ * Note that <code>$menu_data</code> is expected to be pre-slashed.
+ *
  * @since 3.0.0
  *
  * @param int   $menu_id   The ID of the menu or "0" to create a new menu.
@@ -259,6 +264,7 @@ function wp_delete_nav_menu( $menu ) {
  * @return int|WP_Error Menu ID on success, WP_Error object on failure.
  */
 function wp_update_nav_menu_object( $menu_id = 0, $menu_data = array() ) {
+	// expected_slashed ($menu_data)
 	$menu_id = (int) $menu_id;
 
 	$_menu = wp_get_nav_menu_object( $menu_id );

src/wp-includes/widgets/class-wp-nav-menu-widget.php

@@ -92,7 +92,7 @@
 	public function update( $new_instance, $old_instance ) {
 		$instance = array();
 		if ( ! empty( $new_instance['title'] ) ) {
-			$instance['title'] = sanitize_text_field( stripslashes( $new_instance['title'] ) );
+			$instance['title'] = sanitize_text_field( $new_instance['title'] );
 		}
 		if ( ! empty( $new_instance['nav_menu'] ) ) {
 			$instance['nav_menu'] = (int) $new_instance['nav_menu'];

src/wp-includes/widgets/class-wp-widget-tag-cloud.php

@@ -98,7 +98,7 @@ class WP_Widget_Tag_Cloud extends WP_Widget {
 	 */
 	public function update( $new_instance, $old_instance ) {
 		$instance = array();
-		$instance['title'] = sanitize_text_field( stripslashes( $new_instance['title'] ) );
+		$instance['title'] = sanitize_text_field( $new_instance['title'] );
 		$instance['taxonomy'] = stripslashes($new_instance['taxonomy']);
 		return $instance;
 	}

src/wp-includes/widgets/class-wp-widget-text.php

@@ -80,10 +80,11 @@ class WP_Widget_Text extends WP_Widget {
 	public function update( $new_instance, $old_instance ) {
 		$instance = $old_instance;
 		$instance['title'] = sanitize_text_field( $new_instance['title'] );
-		if ( current_user_can('unfiltered_html') )
-			$instance['text'] =  $new_instance['text'];
-		else
-			$instance['text'] = wp_kses_post( stripslashes( $new_instance['text'] ) );
+		if ( current_user_can( 'unfiltered_html' ) ) {
+			$instance['text'] = $new_instance['text'];
+		} else {
+			$instance['text'] = wp_kses_post( $new_instance['text'] );
+		}
 		$instance['filter'] = ! empty( $new_instance['filter'] );
 		return $instance;
 	}