public function state()
{
$end = $this->pathEnd();
return isset($end['id']) || isset($end['name']) ? self::STATE_NAMED : self::STATE_INCOMPLETE;
} /**
* Use another Key's path as the current Key's ancestor
*
* Given key path will be prepended to any path elements on the current key.
*
* Example:
* ```
* $parent = $datastore->key('Person', 'Dad');
* $key->ancestorKey($parent);
* ```
*
* @param Key $key The ancestor Key.
* @return Key
* @throws InvalidArgumentException
*/
public function ancestorKey(Key $key)
{
if ($key->state() !== self::STATE_NAMED) {
throw new InvalidArgumentException('Cannot use an incomplete key as an ancestor');
}
$path = $key->path();
$this->path = array_merge($path, $this->path);
return $this;
}