gistfile1.php

  public function cssClasses($classes, $item) {
    $slug = sanitize_title($item->title);

    if ($item->menu_item_parent == 0) {
      $active_class = 'active';
    } else {
      $active_class = 'active-child';
    }

    if ($this->cpt) {
      $classes = str_replace('current_page_parent', '', $classes);

      if (Utils\url_compare($this->archive, $item->url)) {
        $classes[] = $active_class;
      }
    }

    $classes = preg_replace('/(current(-menu-|[-_]page[-_])(item|parent|ancestor))/', $active_class, $classes);
    $classes = preg_replace('/^((menu|page)[-_\w+]+)+/', '', $classes);

    $classes[] = 'menu-' . $slug;

    $classes = array_unique($classes);

    return array_filter($classes, 'Roots\\Sage\\Utils\\is_element_empty');
  }