/**
* Return all descendant nodes
* @param TreeNode $node
* @return TreeNode[]
*/
private function findAllDescendants(TreeNode $node)
{
$descendants = [];
foreach ($node->findNodes() as $subNode) {
$descendants[$subNode->getKey()] = $subNode;
$descendants += $node->findAllDescendants($subNode);
}
return $descendants;
}
