/**
* recursive way to build tree structure
*
* @param array $keyParts
* @param TreeNode $rootNode
*
* @return TreeNode
*/
protected function createTree(&$keyParts, TreeNode $rootNode) : TreeNode
{
if (!count($keyParts)) {
return $rootNode;
}
$newKey = array_shift($keyParts);
$newNode = new self($rootNode, $newKey, null, $rootNode->getKeyDelimiter());
$rootNode->addChild($newNode);
return $this->createTree($keyParts, $newNode);
}
