JBZoo\Utils\Arr::firstKey PHP Method

    public static function firstKey(array $array)
    {
        reset($array);
        return key($array);
    }

 public function testFirstKey()
 {
     $test = array('a' => array('a' => 'b', 'c' => 'd'));
     is('a', Arr::firstKey(Vars::get($test['a'])));
 }