public static function write(PHPUnit_Extensions_Database_DataSet_IDataSet $dataset, $filename)
{
$pers = new PHPUnit_Extensions_Database_DataSet_Persistors_FlatXml();
$pers->setFileName($filename);
try {
$pers->write($dataset);
} catch (RuntimeException $e) {
throw new PHPUnit_Framework_Exception(__METHOD__ . ' called with an unwritable file.');
}
}