/**
* @param AbstractRevision $revision
* @return AbstractRevision
*/
protected function getRoot(AbstractRevision $revision)
{
if ($revision instanceof PostSummary) {
$topicId = $revision->getSummaryTargetId();
} elseif ($revision instanceof PostRevision && !$revision->isTopicTitle()) {
try {
$topicId = $revision->getCollection()->getWorkflowId();
} catch (DataModelException $e) {
// failed to locate root post (most likely in unit tests, where
// we didn't store the tree)
return $revision;
}
} else {
// if we can't the revision it back to a root, this revision is root
return $revision;
}
$collection = PostCollection::newFromId($topicId);
return $collection->getLastRevision();
}