Text based CAPTCHAs don't call update_response_session()

[nickolasgregory]

As text based CAPTCHAs (riddle, math) are rendered without using the route or controller, the method update_response_session() is never called.
Adding this line before the return (string) in render() will fix this;

$this->update_response_session();

---

I guess making captcha.php like;

public function render($html = TRUE);
{
    if ($html)
        $this->update_response_session();
}

and (eg riddle.php) like;

public function render($html = TRUE)
    parent::render($html);
    return $this->riddle;
}

and taking update_response_session() out of the controller would do the trick.
A bit ugly though. Maybe HMVC is the answer.

Note: the if ($html) above stops update_response_session() being called twice.