code: protected function buildGroupMethod($method, $args = array(), $meta = array())
      {
          $str = '';
          if (\in_array($method, array('group','groupCollapsed'))) {
              $label = \array_shift($args);
              $levelClass = isset($meta['level'])
                  ? 'level-'.$meta['level']
                  : null;
              if (!empty($meta['isMethodName'])) {
                  $label = $this->markupClassname($label);
              }
              foreach ($args as $k => $v) {
                  $args[$k] = $this->dump($v);
              }
              $argStr = \implode(', ', $args);
              /*
                  Header
              */
              $str .= $this->debug->utilities->buildTag(
                  'div',
                  array(
                      'class' => array(
                          'group-header',
                          $method == 'groupCollapsed'
                              ? 'collapsed'
                              : 'expanded',
                          $levelClass,
                      ),
                      'data-channel' => $meta['channel'],
                  ),
                  '<span class="group-label">'
                      .$label
                      .(!empty($argStr)
                          ? '(</span>'.$argStr.'<span class="group-label">)'
                          : '')
                  .'</span>'
              )."\n";
              /*
                  Group open
              */
              $str .= '<div'.$this->debug->utilities->buildAttribString(array(
                  'class' => array(
                      'm_group',
                      $levelClass,
                  ),
              )).'>';
          } elseif ($method == 'groupEnd') {
              $str = '</div>';
          }
          return $str;
      }
docs: handle html output of group, groupCollapsed, & groupEnd
  
  @param string $method group|groupCollapsed|groupEnd
  @param array  $args   args passed to method
  @param array  $meta   meta values
  
  @return string