JS: failing max_length validation on checkbox list with exactly 1 item

[PavelJurasek]

Minimal code in sandbox

protected function createComponentForm()
{
    $form = new Form();
    $form->addCheckboxList('list', NULL, [
        1 => 'one',
    ])->addRule(Form::MAX_LENGTH, 'max is %d', 20);

    $form->addSubmit('submit', 'Submit');
    $form->onSuccess[] = function() {
        dump('success');
    };

    return $form;
}

val.length is undefined (val == TRUE) in netteForms.js

min_length is affected as well

Unfortunately I can't help you with js

[PavelJurasek]

🙏 Thank you!