GetOptionKit\Option::validator PHP Method

    public function validator($cb)
    {
        $this->validator = $cb;
        return $this;
    }

 /**
  * @expectedException InvalidArgumentException
  */
 public function testValidatorReturnValue()
 {
     $opt = new Option('scope');
     $opt->validator(function ($val) {
         return 123454;
     });
     $ret = $opt->validate('public');
 }