WP_Customize_Nav_Menu_Item_Setting::sanitize

	public function sanitize( $menu_item_value ) {
		// Menu is marked for deletion.
		if ( false === $menu_item_value ) {
			return $menu_item_value;
		}

		// Invalid.
		if ( ! is_array( $menu_item_value ) ) {
			return null;
		}

		$default                     = array(
			'object_id'        => 0,
			'object'           => '',
			'menu_item_parent' => 0,
			'position'         => 0,
			'type'             => 'custom',
			'title'            => '',
			'url'              => '',
			'target'           => '',
			'attr_title'       => '',
			'description'      => '',
			'classes'          => '',
			'xfn'              => '',
			'status'           => 'publish',
			'original_title'   => '',
			'nav_menu_term_id' => 0,
			'_invalid'         => false,
		);
		$menu_item_value             = array_merge( $default, $menu_item_value );
		$menu_item_value             = wp_array_slice_assoc( $menu_item_value, array_keys( $default ) );
		$menu_item_value['position'] = intval( $menu_item_value['position'] );

		foreach ( array( 'object_id', 'menu_item_parent', 'nav_menu_term_id' ) as $key ) {
			// Note we need to allow negative-integer IDs for previewed objects not inserted yet.
			$menu_item_value[ $key ] = intval( $menu_item_value[ $key ] );
		}

		foreach ( array( 'type', 'object', 'target' ) as $key ) {
			$menu_item_value[ $key ] = sanitize_key( $menu_item_value[ $key ] );
		}

		foreach ( array( 'xfn', 'classes' ) as $key ) {
			$value = $menu_item_value[ $key ];
			if ( ! is_array( $value ) ) {
				$value = explode( ' ', $value );
			}
			$menu_item_value[ $key ] = implode( ' ', array_map( 'sanitize_html_class', $value ) );
		}

		$menu_item_value['original_title'] = sanitize_text_field( $menu_item_value['original_title'] );

		// Apply the same filters as when calling wp_insert_post().

		/** This filter is documented in wp-includes/post.php */
		$menu_item_value['title'] = wp_unslash( apply_filters( 'title_save_pre', wp_slash( $menu_item_value['title'] ) ) );

		/** This filter is documented in wp-includes/post.php */
		$menu_item_value['attr_title'] = wp_unslash( apply_filters( 'excerpt_save_pre', wp_slash( $menu_item_value['attr_title'] ) ) );

		/** This filter is documented in wp-includes/post.php */
		$menu_item_value['description'] = wp_unslash( apply_filters( 'content_save_pre', wp_slash( $menu_item_value['description'] ) ) );

		if ( '' !== $menu_item_value['url'] ) {
			$menu_item_value['url'] = esc_url_raw( $menu_item_value['url'] );
			if ( '' === $menu_item_value['url'] ) {
				return new WP_Error( 'invalid_url', __( 'Invalid URL.' ) ); // Fail sanitization if URL is invalid.
			}
		}
		if ( 'publish' !== $menu_item_value['status'] ) {
			$menu_item_value['status'] = 'draft';
		}

		$menu_item_value['_invalid'] = (bool) $menu_item_value['_invalid'];

		/** This filter is documented in wp-includes/class-wp-customize-setting.php */
		return apply_filters( "customize_sanitize_{$this->id}", $menu_item_value, $this );
	}