Details::preRenderDetails

public static Details::preRenderDetails($element)

public static function preRenderDetails($element) {
  Element::setAttributes($element, array('id'));

  // The .js-form-wrapper class is required for #states to treat details like
  // containers.
  static::setAttributes($element, array('js-form-wrapper', 'form-wrapper'));

  // Collapsible details.
  $element['#attached']['library'][] = 'core/drupal.collapse';
  if (!empty($element['#open'])) {
    $element['#attributes']['open'] = 'open';
  }

  // Do not render optional details elements if there are no children.
  if (isset($element['#parents'])) {
    $group = implode('][', $element['#parents']);
    if (!empty($element['#optional']) && !Element::getVisibleChildren($element['#groups'][$group])) {
      $element['#printed'] = TRUE;
    }
  }

  return $element;
}