Walker_Page::start_el( string $output, WP_Post $data_object, int $depth = 0, array $args = array(), int $current_object_id = 0 )

105	public function start_el( &$output, $data_object, $depth = 0, $args = array(), $current_object_id = 0 ) {106		// Restores the more descriptive, specific name for use within this method.107		$page = $data_object;108 109		$current_page_id = $current_object_id;110 111		if ( isset( $args['item_spacing'] ) && 'preserve' === $args['item_spacing'] ) {112			$t = "\t";113			$n = "\n";114		} else {115			$t = '';116			$n = '';117		}118		if ( $depth ) {119			$indent = str_repeat( $t, $depth );120		} else {121			$indent = '';122		}123 124		$css_class = array( 'page_item', 'page-item-' . $page->ID );125 126		if ( isset( $args['pages_with_children'][ $page->ID ] ) ) {127			$css_class[] = 'page_item_has_children';128		}129 130		if ( ! empty( $current_page_id ) ) {131			$_current_page = get_post( $current_page_id );132 133			if ( $_current_page && in_array( $page->ID, $_current_page->ancestors, true ) ) {134				$css_class[] = 'current_page_ancestor';135			}136 137			if ( $page->ID === (int) $current_page_id ) {138				$css_class[] = 'current_page_item';139			} elseif ( $_current_page && $page->ID === $_current_page->post_parent ) {140				$css_class[] = 'current_page_parent';141			}142		} elseif ( (int) get_option( 'page_for_posts' ) === $page->ID ) {143			$css_class[] = 'current_page_parent';144		}145 146		/**147		 * Filters the list of CSS classes to include with each page item in the list.148		 *149		 * @since 2.8.0150		 *151		 * @see wp_list_pages()152		 *153		 * @param string[] $css_class       An array of CSS classes to be applied to each list item.154		 * @param WP_Post  $page            Page data object.155		 * @param int      $depth           Depth of page, used for padding.156		 * @param array    $args            An array of arguments.157		 * @param int      $current_page_id ID of the current page.158		 */159		$css_classes = implode( ' ', apply_filters( 'page_css_class', $css_class, $page, $depth, $args, $current_page_id ) );160		$css_classes = $css_classes ? ' class="' . esc_attr( $css_classes ) . '"' : '';161 162		if ( '' === $page->post_title ) {163			/* translators: %d: ID of a post. */164			$page->post_title = sprintf( __( '#%d (no title)' ), $page->ID );165		}166 167		$args['link_before'] = empty( $args['link_before'] ) ? '' : $args['link_before'];168		$args['link_after']  = empty( $args['link_after'] ) ? '' : $args['link_after'];169 170		$atts                 = array();171		$atts['href']         = get_permalink( $page->ID );172		$atts['aria-current'] = ( $page->ID === (int) $current_page_id ) ? 'page' : '';173 174		/**175		 * Filters the HTML attributes applied to a page menu item's anchor element.176		 *177		 * @since 4.8.0178		 *179		 * @param array $atts {180		 *     The HTML attributes applied to the menu item's `<a>` element, empty strings are ignored.181		 *182		 *     @type string $href         The href attribute.183		 *     @type string $aria-current The aria-current attribute.184		 * }