/**
* @param AbstractRevision $revision
* @return MWTimestamp
* @throws Exception
* @throws TimestampException
* @throws \Flow\Exception\DataModelException
*/
protected function getUpdateTimestamp(AbstractRevision $revision)
{
$timestamp = $revision->getRevisionId()->getTimestampObj();
if (!$revision instanceof PostRevision) {
return $timestamp;
}
foreach ($revision->getChildren() as $child) {
// go recursive, find timestamp of most recent child post
$comparison = $this->getUpdateTimestamp($child);
$diff = $comparison->diff($timestamp);
// invert will be 1 if the diff is a negative time period from
// child timestamp ($comparison) to $timestamp, which means that
// $comparison is more recent than our current $timestamp
if ($diff->invert) {
$timestamp = $comparison;
}
}
return $timestamp;
}