function assertValidXhtml($message = null)
{
require_once AK_LIB_DIR . DS . 'AkXhtmlValidator.php';
$response = $this->_response;
$validator = new AkXhtmlValidator();
$valid = $validator->validate($response);
if (!$valid) {
$message = empty($message) ? 'Non valid Xhtml: %errors' : $message;
$message = str_replace('%errors', strip_tags(join("\n- ", $validator->getErrors())), $message);
$this->fail($message);
} else {
$message = empty($message) ? 'XHtml valid' : $message;
$this->pass($message);
}
}
