WordPress 4.0

[autoinstalls/wordpress.git] / wp-admin / includes / nav-menu.php

diff --git a/wp-admin/includes/nav-menu.php b/wp-admin/includes/nav-menu.php
index 7e9fe6ad6425c7f6aff9bdc0ffbf166928ebbc19..44f3ee08435263e7a797ccff328847fb0c95053e 100644 (file)
--- a/wp-admin/includes/nav-menu.php
+++ b/wp-admin/includes/nav-menu.php
@@ -9,36 +9,47 @@
  */
 class Walker_Nav_Menu_Edit extends Walker_Nav_Menu {
        /**
  */
 class Walker_Nav_Menu_Edit extends Walker_Nav_Menu {
        /**

+        * Starts the list before the elements are added.
+        *

         * @see Walker_Nav_Menu::start_lvl()
         * @see Walker_Nav_Menu::start_lvl()

+        *

         * @since 3.0.0
         *
         * @param string $output Passed by reference.
         * @since 3.0.0
         *
         * @param string $output Passed by reference.

+        * @param int    $depth  Depth of menu item. Used for padding.
+        * @param array  $args   Not used.

         */
         */

-       function start_lvl( &$output, $depth = 0, $args = array() ) {}
+       public function start_lvl( &$output, $depth = 0, $args = array() ) {}

 
        /**
 
        /**

+        * Ends the list of after the elements are added.
+        *

         * @see Walker_Nav_Menu::end_lvl()
         * @see Walker_Nav_Menu::end_lvl()

+        *

         * @since 3.0.0
         *
         * @param string $output Passed by reference.
         * @since 3.0.0
         *
         * @param string $output Passed by reference.

+        * @param int    $depth  Depth of menu item. Used for padding.
+        * @param array  $args   Not used.

         */
         */

-       function end_lvl( &$output, $depth = 0, $args = array() ) {}
+       public function end_lvl( &$output, $depth = 0, $args = array() ) {}

 
        /**
 
        /**

-        * @see Walker::start_el()
+        * Start the element output.
+        *
+        * @see Walker_Nav_Menu::start_el()

         * @since 3.0.0
         *
         * @param string $output Passed by reference. Used to append additional content.
         * @since 3.0.0
         *
         * @param string $output Passed by reference. Used to append additional content.

-        * @param object $item Menu item data object.
-        * @param int $depth Depth of menu item. Used for padding.
-        * @param object $args
+        * @param object $item   Menu item data object.
+        * @param int    $depth  Depth of menu item. Used for padding.
+        * @param array  $args   Not used.
+        * @param int    $id     Not used.

         */
         */

-       function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
+       public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {

                global $_wp_nav_menu_max_depth;
                $_wp_nav_menu_max_depth = $depth > $_wp_nav_menu_max_depth ? $depth : $_wp_nav_menu_max_depth;
 
                global $_wp_nav_menu_max_depth;
                $_wp_nav_menu_max_depth = $depth > $_wp_nav_menu_max_depth ? $depth : $_wp_nav_menu_max_depth;
 

-               $indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';
-

                ob_start();
                $item_id = esc_attr( $item->ID );
                $removed_args = array(
                ob_start();
                $item_id = esc_attr( $item->ID );
                $removed_args = array(


@@ -57,7 +68,7 @@ class Walker_Nav_Menu_Edit extends Walker_Nav_Menu {
                                $original_title = false;
                } elseif ( 'post_type' == $item->type ) {
                        $original_object = get_post( $item->object_id );
                                $original_title = false;
                } elseif ( 'post_type' == $item->type ) {
                        $original_object = get_post( $item->object_id );

-                       $original_title = $original_object->post_title;
+                       $original_title = get_the_title( $original_object->ID );

                }
 
                $classes = array(
                }
 
                $classes = array(


@@ -214,42 +225,68 @@ class Walker_Nav_Menu_Edit extends Walker_Nav_Menu {
                <?php
                $output .= ob_get_clean();
        }
                <?php
                $output .= ob_get_clean();
        }

-}
+
+} // Walker_Nav_Menu_Edit

 
 /**
  * Create HTML list of nav menu input items.
  *
 
 /**
  * Create HTML list of nav menu input items.
  *

- * @package WordPress

  * @since 3.0.0
  * @uses Walker_Nav_Menu
  */
 class Walker_Nav_Menu_Checklist extends Walker_Nav_Menu {
  * @since 3.0.0
  * @uses Walker_Nav_Menu
  */
 class Walker_Nav_Menu_Checklist extends Walker_Nav_Menu {

-       function __construct( $fields = false ) {
+       public function __construct( $fields = false ) {

                if ( $fields ) {
                        $this->db_fields = $fields;
                }
        }
 
                if ( $fields ) {
                        $this->db_fields = $fields;
                }
        }
 

-       function start_lvl( &$output, $depth = 0, $args = array() ) {
+       /**
+        * Starts the list before the elements are added.
+        *
+        * @see Walker_Nav_Menu::start_lvl()
+        *
+        * @since 3.0.0
+        *
+        * @param string $output Passed by reference. Used to append additional content.
+        * @param int    $depth  Depth of page. Used for padding.
+        * @param array  $args   Not used.
+        */
+       public function start_lvl( &$output, $depth = 0, $args = array() ) {

                $indent = str_repeat( "\t", $depth );
                $output .= "\n$indent<ul class='children'>\n";
        }
 
                $indent = str_repeat( "\t", $depth );
                $output .= "\n$indent<ul class='children'>\n";
        }
 

-       function end_lvl( &$output, $depth = 0, $args = array() ) {
+       /**
+        * Ends the list of after the elements are added.
+        *
+        * @see Walker_Nav_Menu::end_lvl()
+        *
+        * @since 3.0.0
+        *
+        * @param string $output Passed by reference. Used to append additional content.
+        * @param int    $depth  Depth of page. Used for padding.
+        * @param array  $args   Not used.
+        */
+       public function end_lvl( &$output, $depth = 0, $args = array() ) {

                $indent = str_repeat( "\t", $depth );
                $output .= "\n$indent</ul>";
        }
 
        /**
                $indent = str_repeat( "\t", $depth );
                $output .= "\n$indent</ul>";
        }
 
        /**

-        * @see Walker::start_el()
+        * Start the element output.
+        *
+        * @see Walker_Nav_Menu::start_el()
+        *

         * @since 3.0.0
         *
         * @param string $output Passed by reference. Used to append additional content.
         * @since 3.0.0
         *
         * @param string $output Passed by reference. Used to append additional content.

-        * @param object $item Menu item data object.
-        * @param int $depth Depth of menu item. Used for padding.
-        * @param object $args
+        * @param object $item   Menu item data object.
+        * @param int    $depth  Depth of menu item. Used for padding.
+        * @param array  $args   Not used.
+        * @param int    $id     Not used.

         */
         */

-       function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
+       public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {

                global $_nav_menu_placeholder;
 
                $_nav_menu_placeholder = ( 0 > $_nav_menu_placeholder ) ? intval($_nav_menu_placeholder) - 1 : -1;
                global $_nav_menu_placeholder;
 
                $_nav_menu_placeholder = ( 0 > $_nav_menu_placeholder ) ? intval($_nav_menu_placeholder) - 1 : -1;


@@ -261,15 +298,23 @@ class Walker_Nav_Menu_Checklist extends Walker_Nav_Menu {
                $output .= $indent . '<li>';
                $output .= '<label class="menu-item-title">';
                $output .= '<input type="checkbox" class="menu-item-checkbox';
                $output .= $indent . '<li>';
                $output .= '<label class="menu-item-title">';
                $output .= '<input type="checkbox" class="menu-item-checkbox';

-               if ( property_exists( $item, 'front_or_home' ) && $item->front_or_home ) {
-                       $title = sprintf( _x( 'Home: %s', 'nav menu front page title' ), $item->post_title );
+
+               if ( ! empty( $item->front_or_home ) )

                        $output .= ' add-to-top';
                        $output .= ' add-to-top';

-               } elseif ( property_exists( $item, 'label' ) ) {
+
+               $output .= '" name="menu-item[' . $possible_object_id . '][menu-item-object-id]" value="'. esc_attr( $item->object_id ) .'" /> ';
+
+               if ( ! empty( $item->label ) ) {

                        $title = $item->label;
                        $title = $item->label;

+               } elseif ( isset( $item->post_type ) ) {
+                       /** This filter is documented in wp-includes/post-template.php */
+                       $title = apply_filters( 'the_title', $item->post_title, $item->ID );
+                       if ( ! empty( $item->front_or_home ) && _x( 'Home', 'nav menu home label' ) !== $title )
+                               $title = sprintf( _x( 'Home: %s', 'nav menu front page title' ), $title );

                }
                }

-               $output .= '" name="menu-item[' . $possible_object_id . '][menu-item-object-id]" value="'. esc_attr( $item->object_id ) .'" /> ';
+

                $output .= isset( $title ) ? esc_html( $title ) : esc_html( $item->title );
                $output .= isset( $title ) ? esc_html( $title ) : esc_html( $item->title );

-               $output .= '</label>';
+               $output .= '</label>';

 
                // Menu item hidden fields
                $output .= '<input type="hidden" class="menu-item-db-id" name="menu-item[' . $possible_object_id . '][menu-item-db-id]" value="' . $possible_db_id . '" />';
 
                // Menu item hidden fields
                $output .= '<input type="hidden" class="menu-item-db-id" name="menu-item[' . $possible_object_id . '][menu-item-db-id]" value="' . $possible_db_id . '" />';


@@ -283,7 +328,8 @@ class Walker_Nav_Menu_Checklist extends Walker_Nav_Menu {
                $output .= '<input type="hidden" class="menu-item-classes" name="menu-item[' . $possible_object_id . '][menu-item-classes]" value="'. esc_attr( implode( ' ', $item->classes ) ) .'" />';
                $output .= '<input type="hidden" class="menu-item-xfn" name="menu-item[' . $possible_object_id . '][menu-item-xfn]" value="'. esc_attr( $item->xfn ) .'" />';
        }
                $output .= '<input type="hidden" class="menu-item-classes" name="menu-item[' . $possible_object_id . '][menu-item-classes]" value="'. esc_attr( implode( ' ', $item->classes ) ) .'" />';
                $output .= '<input type="hidden" class="menu-item-xfn" name="menu-item[' . $possible_object_id . '][menu-item-xfn]" value="'. esc_attr( $item->xfn ) .'" />';
        }

-}
+
+} // Walker_Nav_Menu_Checklist

 
 /**
  * Prints the appropriate response to a menu quick search.
 
 /**
  * Prints the appropriate response to a menu quick search.


@@ -310,7 +356,6 @@ function _wp_ajax_menu_quick_search( $request = array() ) {
                                if ( 'markup' == $response_format ) {
                                        echo walk_nav_menu_tree( array_map('wp_setup_nav_menu_item', array( get_post( $object_id ) ) ), 0, (object) $args );
                                } elseif ( 'json' == $response_format ) {
                                if ( 'markup' == $response_format ) {
                                        echo walk_nav_menu_tree( array_map('wp_setup_nav_menu_item', array( get_post( $object_id ) ) ), 0, (object) $args );
                                } elseif ( 'json' == $response_format ) {

-                                       $post_obj = get_post( $object_id );

                                        echo json_encode(
                                                array(
                                                        'ID' => $object_id,
                                        echo json_encode(
                                                array(
                                                        'ID' => $object_id,


@@ -456,10 +501,22 @@ function wp_nav_menu_post_type_meta_boxes() {
                return;
 
        foreach ( $post_types as $post_type ) {
                return;
 
        foreach ( $post_types as $post_type ) {

+               /**
+                * Filter whether a menu items meta box will be added for the current
+                * object type.
+                *
+                * If a falsey value is returned instead of an object, the menu items
+                * meta box for the current meta box object will not be added.
+                *
+                * @since 3.0.0
+                *
+                * @param object $meta_box_object The current object to add a menu items
+                *                                meta box for.
+                */

                $post_type = apply_filters( 'nav_menu_meta_box_object', $post_type );
                if ( $post_type ) {
                        $id = $post_type->name;
                $post_type = apply_filters( 'nav_menu_meta_box_object', $post_type );
                if ( $post_type ) {
                        $id = $post_type->name;

-                       // give pages a higher priority
+                       // Give pages a higher priority.

                        $priority = ( 'page' == $post_type->name ? 'core' : 'default' );
                        add_meta_box( "add-{$id}", $post_type->labels->name, 'wp_nav_menu_item_post_type_meta_box', 'nav-menus', 'side', $priority, $post_type );
                }
                        $priority = ( 'page' == $post_type->name ? 'core' : 'default' );
                        add_meta_box( "add-{$id}", $post_type->labels->name, 'wp_nav_menu_item_post_type_meta_box', 'nav-menus', 'side', $priority, $post_type );
                }


@@ -478,6 +535,7 @@ function wp_nav_menu_taxonomy_meta_boxes() {
                return;
 
        foreach ( $taxonomies as $tax ) {
                return;
 
        foreach ( $taxonomies as $tax ) {

+               /** This filter is documented in wp-admin/includes/nav-menu.php */

                $tax = apply_filters( 'nav_menu_meta_box_object', $tax );
                if ( $tax ) {
                        $id = $tax->name;
                $tax = apply_filters( 'nav_menu_meta_box_object', $tax );
                if ( $tax ) {
                        $id = $tax->name;


@@ -486,51 +544,6 @@ function wp_nav_menu_taxonomy_meta_boxes() {
        }
 }
 
        }
 }
 

-/**
- * Displays a metabox for the nav menu theme locations.
- *
- * @since 3.0.0
- */
-function wp_nav_menu_locations_meta_box() {
-       global $nav_menu_selected_id;
-
-       if ( ! current_theme_supports( 'menus' ) ) {
-               // We must only support widgets. Leave a message and bail.
-               echo '<p class="howto">' . __('The current theme does not natively support menus, but you can use the &#8220;Custom Menu&#8221; widget to add any menus you create here to the theme&#8217;s sidebar.') . '</p>';
-               return;
-       }
-
-       $locations = get_registered_nav_menus();
-       $menus = wp_get_nav_menus();
-       $menu_locations = get_nav_menu_locations();
-       $num_locations = count( array_keys($locations) );
-
-       echo '<p class="howto">' . _n( 'Select a menu to use within your theme.', 'Select the menus you will use in your theme.', $num_locations ) . '</p>';
-
-       foreach ( $locations as $location => $description ) {
-               ?>
-               <p>
-                       <label class="howto" for="locations-<?php echo $location; ?>">
-                               <span><?php echo $description; ?></span>
-                               <select name="menu-locations[<?php echo $location; ?>]" id="locations-<?php echo $location; ?>">
-                                       <option value="0"></option>
-                                       <?php foreach ( $menus as $menu ) : ?>
-                                       <option<?php selected( isset( $menu_locations[ $location ] ) && $menu_locations[ $location ] == $menu->term_id ); ?>
-                                               value="<?php echo $menu->term_id; ?>"><?php echo wp_html_excerpt( $menu->name, 40, '&hellip;' ); ?></option>
-                                       <?php endforeach; ?>
-                               </select>
-                       </label>
-               </p>
-       <?php
-       }
-       ?>
-       <p class="button-controls">
-               <?php submit_button( __( 'Save' ), 'primary right', 'nav-menu-locations', false, wp_nav_menu_disabled_check( $nav_menu_selected_id ) ); ?>
-               <span class="spinner"></span>
-       </p>
-       <?php
-}
-

 /**
  * Check whether to disable the Menu Locations meta box submit button
  *
 /**
  * Check whether to disable the Menu Locations meta box submit button
  *


@@ -602,7 +615,7 @@ function wp_nav_menu_item_post_type_meta_box( $object, $post_type ) {
 
        $post_type_name = $post_type['args']->name;
 
 
        $post_type_name = $post_type['args']->name;
 

-       // paginate browsing for large numbers of post objects
+       // Paginate browsing for large numbers of post objects.

        $per_page = 50;
        $pagenum = isset( $_REQUEST[$post_type_name . '-tab'] ) && isset( $_REQUEST['paged'] ) ? absint( $_REQUEST['paged'] ) : 1;
        $offset = 0 < $pagenum ? $per_page * ( $pagenum - 1 ) : 0;
        $per_page = 50;
        $pagenum = isset( $_REQUEST[$post_type_name . '-tab'] ) && isset( $_REQUEST['paged'] ) ? absint( $_REQUEST['paged'] ) : 1;
        $offset = 0 < $pagenum ? $per_page * ( $pagenum - 1 ) : 0;


@@ -629,8 +642,6 @@ function wp_nav_menu_item_post_type_meta_box( $object, $post_type ) {
                return;
        }
 
                return;
        }
 

-       $post_type_object = get_post_type_object($post_type_name);
-

        $num_pages = $get_posts->max_num_pages;
 
        $page_links = paginate_links( array(
        $num_pages = $get_posts->max_num_pages;
 
        $page_links = paginate_links( array(


@@ -649,9 +660,6 @@ function wp_nav_menu_item_post_type_meta_box( $object, $post_type ) {
                'current' => $pagenum
        ));
 
                'current' => $pagenum
        ));
 

-       if ( !$posts )
-               $error = '<li id="error">'. $post_type['args']->labels->not_found .'</li>';
-

        $db_fields = false;
        if ( is_post_type_hierarchical( $post_type_name ) ) {
                $db_fields = array( 'parent' => 'post_parent', 'id' => 'ID' );
        $db_fields = false;
        if ( is_post_type_hierarchical( $post_type_name ) ) {
                $db_fields = array( 'parent' => 'post_parent', 'id' => 'ID' );


@@ -754,7 +762,10 @@ function wp_nav_menu_item_post_type_meta_box( $object, $post_type ) {
                                <?php
                                $args['walker'] = $walker;
 
                                <?php
                                $args['walker'] = $walker;
 

-                               // if we're dealing with pages, let's put a checkbox for the front page at the top of the list
+                               /*
+                                * If we're dealing with pages, let's put a checkbox for the front
+                                * page at the top of the list.
+                                */

                                if ( 'page' == $post_type_name ) {
                                        $front_page = 'page' == get_option('show_on_front') ? (int) get_option( 'page_on_front' ) : 0;
                                        if ( ! empty( $front_page ) ) {
                                if ( 'page' == $post_type_name ) {
                                        $front_page = 'page' == get_option('show_on_front') ? (int) get_option( 'page_on_front' ) : 0;
                                        if ( ! empty( $front_page ) ) {


@@ -778,7 +789,22 @@ function wp_nav_menu_item_post_type_meta_box( $object, $post_type ) {
                                        }
                                }
 
                                        }
                                }
 

-                               $posts = apply_filters( 'nav_menu_items_'.$post_type_name, $posts, $args, $post_type );
+                               /**
+                                * Filter the posts displayed in the 'View All' tab of the current
+                                * post type's menu items meta box.
+                                *
+                                * The dynamic portion of the hook name, $post_type_name,
+                                * refers to the slug of the current post type.
+                                *
+                                * @since 3.2.0
+                                *
+                                * @see WP_Query::query()
+                                *
+                                * @param array  $posts     The posts for the current post type.
+                                * @param array  $args      An array of WP_Query arguments.
+                                * @param object $post_type The current post type object for this menu item meta box.
+                                */
+                               $posts = apply_filters( "nav_menu_items_{$post_type_name}", $posts, $args, $post_type );

                                $checkbox_items = walk_nav_menu_tree( array_map('wp_setup_nav_menu_item', $posts), 0, (object) $args );
 
                                if ( 'all' == $current_tab && ! empty( $_REQUEST['selectall'] ) ) {
                                $checkbox_items = walk_nav_menu_tree( array_map('wp_setup_nav_menu_item', $posts), 0, (object) $args );
 
                                if ( 'all' == $current_tab && ! empty( $_REQUEST['selectall'] ) ) {


@@ -810,7 +836,7 @@ function wp_nav_menu_item_post_type_meta_box( $object, $post_type ) {
                        </span>
 
                        <span class="add-to-menu">
                        </span>
 
                        <span class="add-to-menu">

-                               <input type="submit"<?php wp_nav_menu_disabled_check( $nav_menu_selected_id ); ?> class="button-secondary submit-add-to-menu right" value="<?php esc_attr_e( __( 'Add to Menu' ) ); ?>" name="add-post-type-menu-item" id="<?php esc_attr_e( 'submit-posttype-' . $post_type_name ); ?>" />
+                               <input type="submit"<?php wp_nav_menu_disabled_check( $nav_menu_selected_id ); ?> class="button-secondary submit-add-to-menu right" value="<?php esc_attr_e( 'Add to Menu' ); ?>" name="add-post-type-menu-item" id="<?php echo esc_attr( 'submit-posttype-' . $post_type_name ); ?>" />

                                <span class="spinner"></span>
                        </span>
                </p>
                                <span class="spinner"></span>
                        </span>
                </p>


@@ -831,7 +857,7 @@ function wp_nav_menu_item_taxonomy_meta_box( $object, $taxonomy ) {
        global $nav_menu_selected_id;
        $taxonomy_name = $taxonomy['args']->name;
 
        global $nav_menu_selected_id;
        $taxonomy_name = $taxonomy['args']->name;
 

-       // paginate browsing for large numbers of objects
+       // Paginate browsing for large numbers of objects.

        $per_page = 50;
        $pagenum = isset( $_REQUEST[$taxonomy_name . '-tab'] ) && isset( $_REQUEST['paged'] ) ? absint( $_REQUEST['paged'] ) : 1;
        $offset = 0 < $pagenum ? $per_page * ( $pagenum - 1 ) : 0;
        $per_page = 50;
        $pagenum = isset( $_REQUEST[$taxonomy_name . '-tab'] ) && isset( $_REQUEST['paged'] ) ? absint( $_REQUEST['paged'] ) : 1;
        $offset = 0 < $pagenum ? $per_page * ( $pagenum - 1 ) : 0;


@@ -998,7 +1024,7 @@ function wp_nav_menu_item_taxonomy_meta_box( $object, $taxonomy ) {
                        </span>
 
                        <span class="add-to-menu">
                        </span>
 
                        <span class="add-to-menu">

-                               <input type="submit"<?php wp_nav_menu_disabled_check( $nav_menu_selected_id ); ?> class="button-secondary submit-add-to-menu right" value="<?php esc_attr_e( __( 'Add to Menu' ) ); ?>" name="add-taxonomy-menu-item" id="<?php esc_attr_e( 'submit-taxonomy-' . $taxonomy_name ); ?>" />
+                               <input type="submit"<?php wp_nav_menu_disabled_check( $nav_menu_selected_id ); ?> class="button-secondary submit-add-to-menu right" value="<?php esc_attr_e( 'Add to Menu' ); ?>" name="add-taxonomy-menu-item" id="<?php echo esc_attr( 'submit-taxonomy-' . $taxonomy_name ); ?>" />

                                <span class="spinner"></span>
                        </span>
                </p>
                                <span class="spinner"></span>
                        </span>
                </p>


@@ -1022,21 +1048,26 @@ function wp_save_nav_menu_items( $menu_id = 0, $menu_data = array() ) {
 
        if ( 0 == $menu_id || is_nav_menu( $menu_id ) ) {
 
 
        if ( 0 == $menu_id || is_nav_menu( $menu_id ) ) {
 

-               // Loop through all the menu items' POST values
+               // Loop through all the menu items' POST values.

                foreach( (array) $menu_data as $_possible_db_id => $_item_object_data ) {
                        if (
                foreach( (array) $menu_data as $_possible_db_id => $_item_object_data ) {
                        if (

-                               empty( $_item_object_data['menu-item-object-id'] ) && // checkbox is not checked
+                               // Checkbox is not checked.
+                               empty( $_item_object_data['menu-item-object-id'] ) &&

                                (
                                (

-                                       ! isset( $_item_object_data['menu-item-type'] ) || // and item type either isn't set
-                                       in_array( $_item_object_data['menu-item-url'], array( 'http://', '' ) ) || // or URL is the default
+                                       // And item type either isn't set.
+                                       ! isset( $_item_object_data['menu-item-type'] ) ||
+                                       // Or URL is the default.
+                                       in_array( $_item_object_data['menu-item-url'], array( 'http://', '' ) ) ||

                                        ! ( 'custom' == $_item_object_data['menu-item-type'] && ! isset( $_item_object_data['menu-item-db-id'] ) ) || // or it's not a custom menu item (but not the custom home page)
                                        ! ( 'custom' == $_item_object_data['menu-item-type'] && ! isset( $_item_object_data['menu-item-db-id'] ) ) || // or it's not a custom menu item (but not the custom home page)

-                                       ! empty( $_item_object_data['menu-item-db-id'] ) // or it *is* a custom menu item that already exists
+                                       // Or it *is* a custom menu item that already exists.
+                                       ! empty( $_item_object_data['menu-item-db-id'] )

                                )
                        ) {
                                )
                        ) {

-                               continue; // then this potential menu item is not getting added to this menu
+                               // Then this potential menu item is not getting added to this menu.
+                               continue;

                        }
 
                        }
 

-                       // if this possible menu item doesn't actually have a menu database ID yet
+                       // If this possible menu item doesn't actually have a menu database ID yet.

                        if (
                                empty( $_item_object_data['menu-item-db-id'] ) ||
                                ( 0 > $_possible_db_id ) ||
                        if (
                                empty( $_item_object_data['menu-item-db-id'] ) ||
                                ( 0 > $_possible_db_id ) ||


@@ -1089,20 +1120,20 @@ function _wp_nav_menu_meta_box_object( $object = null ) {
                                'post_status' => 'publish',
                        );
 
                                'post_status' => 'publish',
                        );
 

-               // posts should show only published items
+               // Posts should show only published items.

                } elseif ( 'post' == $object->name ) {
                        $object->_default_query = array(
                                'post_status' => 'publish',
                        );
 
                } elseif ( 'post' == $object->name ) {
                        $object->_default_query = array(
                                'post_status' => 'publish',
                        );
 

-               // cats should be in reverse chronological order
+               // Categories should be in reverse chronological order.

                } elseif ( 'category' == $object->name ) {
                        $object->_default_query = array(
                                'orderby' => 'id',
                                'order' => 'DESC',
                        );
 
                } elseif ( 'category' == $object->name ) {
                        $object->_default_query = array(
                                'orderby' => 'id',
                                'order' => 'DESC',
                        );
 

-               // custom post types should show only published items
+               // Custom post types should show only published items.

                } else {
                        $object->_default_query = array(
                                'post_status' => 'publish',
                } else {
                        $object->_default_query = array(
                                'post_status' => 'publish',


@@ -1135,6 +1166,14 @@ function wp_get_nav_menu_to_edit( $menu_id = 0 ) {
                if( empty($menu_items) )
                        return $result . ' <ul class="menu" id="menu-to-edit"> </ul>';
 
                if( empty($menu_items) )
                        return $result . ' <ul class="menu" id="menu-to-edit"> </ul>';
 

+               /**
+                * Filter the Walker class used when adding nav menu items.
+                *
+                * @since 3.0.0
+                *
+                * @param string $class   The walker class to use. Default 'Walker_Nav_Menu_Edit'.
+                * @param int    $menu_id ID of the menu being rendered.
+                */

                $walker_class_name = apply_filters( 'wp_edit_nav_menu_walker', 'Walker_Nav_Menu_Edit', $menu_id );
 
                if ( class_exists( $walker_class_name ) )
                $walker_class_name = apply_filters( 'wp_edit_nav_menu_walker', 'Walker_Nav_Menu_Edit', $menu_id );
 
                if ( class_exists( $walker_class_name ) )


@@ -1195,7 +1234,7 @@ function _wp_delete_orphaned_draft_menu_items() {
        global $wpdb;
        $delete_timestamp = time() - ( DAY_IN_SECONDS * EMPTY_TRASH_DAYS );
 
        global $wpdb;
        $delete_timestamp = time() - ( DAY_IN_SECONDS * EMPTY_TRASH_DAYS );
 

-       // delete orphaned draft menu items
+       // Delete orphaned draft menu items.

        $menu_items_to_delete = $wpdb->get_col($wpdb->prepare("SELECT ID FROM $wpdb->posts AS p LEFT JOIN $wpdb->postmeta AS m ON p.ID = m.post_id WHERE post_type = 'nav_menu_item' AND post_status = 'draft' AND meta_key = '_menu_item_orphaned' AND meta_value < '%d'", $delete_timestamp ) );
 
        foreach( (array) $menu_items_to_delete as $menu_item_id )
        $menu_items_to_delete = $wpdb->get_col($wpdb->prepare("SELECT ID FROM $wpdb->posts AS p LEFT JOIN $wpdb->postmeta AS m ON p.ID = m.post_id WHERE post_type = 'nav_menu_item' AND post_status = 'draft' AND meta_key = '_menu_item_orphaned' AND meta_value < '%d'", $delete_timestamp ) );
 
        foreach( (array) $menu_items_to_delete as $menu_item_id )


@@ -1279,6 +1318,7 @@ function wp_nav_menu_update_menu_items ( $nav_menu_selected_id, $nav_menu_select
 
        wp_defer_term_counting( false );
 
 
        wp_defer_term_counting( false );
 

+       /** This action is documented in wp-includes/nav-menu.php */

        do_action( 'wp_update_nav_menu', $nav_menu_selected_id );
 
        $messages[] = '<div id="message" class="updated"><p>' . sprintf( __( '<strong>%1$s</strong> has been updated.' ), $nav_menu_selected_title ) . '</p></div>';
        do_action( 'wp_update_nav_menu', $nav_menu_selected_id );
 
        $messages[] = '<div id="message" class="updated"><p>' . sprintf( __( '<strong>%1$s</strong> has been updated.' ), $nav_menu_selected_title ) . '</p></div>';