_user_cancel

_user_cancel($edit, $account, $method)

function _user_cancel($edit, $account, $method) {
  $logger = \Drupal::logger('user');

  switch ($method) {
    case 'user_cancel_block':
    case 'user_cancel_block_unpublish':
    default:
      // Send account blocked notification if option was checked.
      if (!empty($edit['user_cancel_notify'])) {
        _user_mail_notify('status_blocked', $account);
      }
      $account->block();
      $account->save();
      drupal_set_message(t('%name has been disabled.', array('%name' => $account->getDisplayName())));
      $logger->notice('Blocked user: %name %email.', array('%name' => $account->getAccountName(), '%email' => '<' . $account->getEmail() . '>'));
      break;

    case 'user_cancel_reassign':
    case 'user_cancel_delete':
      // Send account canceled notification if option was checked.
      if (!empty($edit['user_cancel_notify'])) {
        _user_mail_notify('status_canceled', $account);
      }
      $account->delete();
      drupal_set_message(t('%name has been deleted.', array('%name' => $account->getDisplayName())));
      $logger->notice('Deleted user: %name %email.', array('%name' => $account->getAccountName(), '%email' => '<' . $account->getEmail() . '>'));
      break;
  }

  // After cancelling account, ensure that user is logged out. We can't destroy
  // their session though, as we might have information in it, and we can't
  // regenerate it because batch API uses the session ID, we will regenerate it
  // in _user_cancel_session_regenerate().
  if ($account->id() == \Drupal::currentUser()->id()) {
    \Drupal::currentUser()->setAccount(new AnonymousUserSession());
  }
}