ItemDataProvider::separateFieldsByParam

protected function separateFieldsByParam(array $fields, string $paramName, $paramValue): array
{
	$separated = [];
	foreach ($fields as $fieldName => $fieldParams)
	{
		if (isset($fieldParams[$paramName]) && $fieldParams[$paramName] === $paramValue)
		{
			$separated[$fieldName] = $fieldParams;
		}
	}

	return $separated;
}