diff -r 490d5cc509ed -r cf61fcea0001 wp/wp-includes/widgets/class-wp-nav-menu-widget.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/widgets/class-wp-nav-menu-widget.php	Mon Oct 14 17:39:30 2019 +0200
@@ -0,0 +1,159 @@
+<?php
+/**
+ * Widget API: WP_Nav_Menu_Widget class
+ *
+ * @package WordPress
+ * @subpackage Widgets
+ * @since 4.4.0
+ */
+
+/**
+ * Core class used to implement the Navigation Menu widget.
+ *
+ * @since 3.0.0
+ *
+ * @see WP_Widget
+ */
+class WP_Nav_Menu_Widget extends WP_Widget {
+
+	/**
+	 * Sets up a new Navigation Menu widget instance.
+	 *
+	 * @since 3.0.0
+	 */
+	public function __construct() {
+		$widget_ops = array(
+			'description' => __( 'Add a navigation menu to your sidebar.' ),
+			'customize_selective_refresh' => true,
+		);
+		parent::__construct( 'nav_menu', __('Navigation Menu'), $widget_ops );
+	}
+
+	/**
+	 * Outputs the content for the current Navigation Menu widget instance.
+	 *
+	 * @since 3.0.0
+	 *
+	 * @param array $args     Display arguments including 'before_title', 'after_title',
+	 *                        'before_widget', and 'after_widget'.
+	 * @param array $instance Settings for the current Navigation Menu widget instance.
+	 */
+	public function widget( $args, $instance ) {
+		// Get menu
+		$nav_menu = ! empty( $instance['nav_menu'] ) ? wp_get_nav_menu_object( $instance['nav_menu'] ) : false;
+
+		if ( ! $nav_menu ) {
+			return;
+		}
+
+		$title = ! empty( $instance['title'] ) ? $instance['title'] : '';
+
+		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */
+		$title = apply_filters( 'widget_title', $title, $instance, $this->id_base );
+
+		echo $args['before_widget'];
+
+		if ( $title ) {
+			echo $args['before_title'] . $title . $args['after_title'];
+		}
+
+		$nav_menu_args = array(
+			'fallback_cb' => '',
+			'menu'        => $nav_menu
+		);
+
+		/**
+		 * Filters the arguments for the Navigation Menu widget.
+		 *
+		 * @since 4.2.0
+		 * @since 4.4.0 Added the `$instance` parameter.
+		 *
+		 * @param array    $nav_menu_args {
+		 *     An array of arguments passed to wp_nav_menu() to retrieve a navigation menu.
+		 *
+		 *     @type callable|bool $fallback_cb Callback to fire if the menu doesn't exist. Default empty.
+		 *     @type mixed         $menu        Menu ID, slug, or name.
+		 * }
+		 * @param WP_Term  $nav_menu      Nav menu object for the current menu.
+		 * @param array    $args          Display arguments for the current widget.
+		 * @param array    $instance      Array of settings for the current widget.
+		 */
+		wp_nav_menu( apply_filters( 'widget_nav_menu_args', $nav_menu_args, $nav_menu, $args, $instance ) );
+
+		echo $args['after_widget'];
+	}
+
+	/**
+	 * Handles updating settings for the current Navigation Menu widget instance.
+	 *
+	 * @since 3.0.0
+	 *
+	 * @param array $new_instance New settings for this instance as input by the user via
+	 *                            WP_Widget::form().
+	 * @param array $old_instance Old settings for this instance.
+	 * @return array Updated settings to save.
+	 */
+	public function update( $new_instance, $old_instance ) {
+		$instance = array();
+		if ( ! empty( $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'];
+		}
+		return $instance;
+	}
+
+	/**
+	 * Outputs the settings form for the Navigation Menu widget.
+	 *
+	 * @since 3.0.0
+	 *
+	 * @param array $instance Current settings.
+	 * @global WP_Customize_Manager $wp_customize
+	 */
+	public function form( $instance ) {
+		global $wp_customize;
+		$title = isset( $instance['title'] ) ? $instance['title'] : '';
+		$nav_menu = isset( $instance['nav_menu'] ) ? $instance['nav_menu'] : '';
+
+		// Get menus
+		$menus = wp_get_nav_menus();
+
+		// If no menus exists, direct the user to go and create some.
+		?>
+		<p class="nav-menu-widget-no-menus-message" <?php if ( ! empty( $menus ) ) { echo ' style="display:none" '; } ?>>
+			<?php
+			if ( $wp_customize instanceof WP_Customize_Manager ) {
+				$url = 'javascript: wp.customize.panel( "nav_menus" ).focus();';
+			} else {
+				$url = admin_url( 'nav-menus.php' );
+			}
+			?>
+			<?php echo sprintf( __( 'No menus have been created yet. <a href="%s">Create some</a>.' ), esc_attr( $url ) ); ?>
+		</p>
+		<div class="nav-menu-widget-form-controls" <?php if ( empty( $menus ) ) { echo ' style="display:none" '; } ?>>
+			<p>
+				<label for="<?php echo $this->get_field_id( 'title' ); ?>"><?php _e( 'Title:' ) ?></label>
+				<input type="text" class="widefat" id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" value="<?php echo esc_attr( $title ); ?>"/>
+			</p>
+			<p>
+				<label for="<?php echo $this->get_field_id( 'nav_menu' ); ?>"><?php _e( 'Select Menu:' ); ?></label>
+				<select id="<?php echo $this->get_field_id( 'nav_menu' ); ?>" name="<?php echo $this->get_field_name( 'nav_menu' ); ?>">
+					<option value="0"><?php _e( '&mdash; Select &mdash;' ); ?></option>
+					<?php foreach ( $menus as $menu ) : ?>
+						<option value="<?php echo esc_attr( $menu->term_id ); ?>" <?php selected( $nav_menu, $menu->term_id ); ?>>
+							<?php echo esc_html( $menu->name ); ?>
+						</option>
+					<?php endforeach; ?>
+				</select>
+			</p>
+			<?php if ( $wp_customize instanceof WP_Customize_Manager ) : ?>
+				<p class="edit-selected-nav-menu" style="<?php if ( ! $nav_menu ) { echo 'display: none;'; } ?>">
+					<button type="button" class="button"><?php _e( 'Edit Menu' ) ?></button>
+				</p>
+			<?php endif; ?>
+		</div>
+		<?php
+	}
+}