BP_Walker_Nav_Menu::start_el( string $output, object $item, int $depth, array $args = array(), int $id )

	public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
		// If we're someway down the tree, indent the HTML with the appropriate number of tabs.
		$indent = $depth ? str_repeat( "\t", $depth ) : '';

		/**
		 * Filters the classes to be added to the nav menu markup.
		 *
		 * @since BuddyPress 1.7.0
		 *
		 * @param array  $value Array of classes to be added.
		 * @param object $item  Menu item data object.
		 * @param array  $args  Array of arguments for the item.
		 */
		$class_names = join( ' ', apply_filters( 'bp_nav_menu_css_class', array_filter( $item->class ), $item, $args ) );
		$class_names = ! empty( $class_names ) ? ' class="' . esc_attr( $class_names ) . '"' : '';

		// Add HTML ID
		$id = sanitize_html_class( $item->css_id . '-personal-li' );  // Backpat with BP pre-1.7.

		/**
		 * Filters the value to be used for the nav menu ID attribute.
		 *
		 * @since BuddyPress 1.7.0
		 *
		 * @param string $id   ID attribute to be added to the menu item.
		 * @param object $item Menu item data object.
		 * @param array  $args Array of arguments for the item.
		 */
		$id = apply_filters( 'bp_nav_menu_item_id', $id, $item, $args );
		$id = ! empty( $id ) ? ' id="' . esc_attr( $id ) . '"' : '';

		// Opening tag; closing tag is handled in Walker_Nav_Menu::end_el().
		$output .= $indent . '<li' . $id . $class_names . '>';

		// Add href attribute.
		$attributes = ! empty( $item->link ) ? ' href="' . esc_url( $item->link ) . '"' : '';

		// Construct the link.
		$item_output = $args->before;
		$item_output .= '<a' . $attributes . '>';

		/**
		 * Filters the link text to be added to the item output.
		 *
		 * @since BuddyPress 1.7.0
		 *
		 * @param string $name  Item text to be applied.
		 * @param int    $value Post ID the title is for.
		 */
		$item_output .= $args->link_before . apply_filters( 'the_title', $item->name, 0 ) . $args->link_after;
		$item_output .= '</a>';
		$item_output .= $args->after;

		/**
		 * Filters the final result for the menu item.
		 *
		 * @since BuddyPress 1.7.0
		 *
		 * @param string $item_output Constructed output for the menu item to append to output.
		 * @param object $item        Menu item data object.
		 * @param int    $depth       Depth of menu item. Used for padding.
		 * @param array  $args        Array of arguments for the item.
		 */
		$output .= apply_filters( 'bp_walker_nav_menu_start_el', $item_output, $item, $depth, $args );
	}