book_node_type_update

book_node_type_update(NodeTypeInterface $type)

function book_node_type_update(NodeTypeInterface $type) {
  if ($type->getOriginalId() != $type->id()) {
    $config = \Drupal::configFactory()->getEditable('book.settings');
    // Update the list of node types that are allowed to be added to books.
    $allowed_types = $config->get('allowed_types');
    $old_key = array_search($type->getOriginalId(), $allowed_types);

    if ($old_key !== FALSE) {
      $allowed_types[$old_key] = $type->id();
      // Ensure that the allowed_types array is sorted consistently.
      // @see BookSettingsForm::submitForm()
      sort($allowed_types);
      $config->set('allowed_types', $allowed_types);
    }

    // Update the setting for the "Add child page" link.
    if ($config->get('child_type') == $type->getOriginalId()) {
      $config->set('child_type', $type->id());
    }
    $config->save();
  }
}