DataLoader::getPreparedFilter

protected function getPreparedFilter(array $fields)
{
	$result = [];
	$filter = $this->getFilter();
	if (!empty($filter) && is_array($filter))
	{
		$dataFilter = new DataFilter();
		$dataFilter->setFields($fields);
		$result = $dataFilter->create($filter);
		unset($dataFilter);
	}
	return $result;
}