<!doctype html>

<script src="../../resources/js-test.js"></script>

<!--
    Each frameset starts with frameborder="no" (border off, so the two columns
    fill the 300px-wide iframe at 150px each). With border="10" turned back on
    the single vertical border between the columns leaves 290px to split, so the
    frames become 145px each. We use that 150<->145 difference to observe the
    m_frameborder state after a dynamic change.
-->
<iframe id="restored-by-yes" data-assert-off-width="150" data-assert-on-width="145">
    <!doctype html>
    <frameset rows="*" cols="50,50" frameborder="no" border="10">
        <frame src="data:text/html,<body bgcolor=red>">
        <frame src="data:text/html,<body bgcolor=blue>">
    </frameset>
</iframe>

<iframe id="restored-by-removal" data-assert-off-width="150" data-assert-on-width="145">
    <!doctype html>
    <frameset rows="*" cols="50,50" frameborder="no" border="10">
        <frame src="data:text/html,<body bgcolor=red>">
        <frame src="data:text/html,<body bgcolor=blue>">
    </frameset>
</iframe>

<script>
    description('Tests that the frameset frameborder state updates correctly on dynamic changes: ' +
        'changing frameborder="no" to a true value restores the border, and removing the attribute ' +
        'restores the default (true) rather than forcing it off.');

    function framesetIn(iframe) {
        // Can't use srcdoc since that wouldn't synchronously load the content.
        iframe.contentDocument.write(iframe.textContent);
        iframe.contentDocument.close();
        return iframe.contentDocument.querySelector('frameset');
    }

    var offWidth = '150';
    var onWidth = '145';

    debug('Changing frameborder="no" to frameborder="yes" restores the border:');
    var frameset = framesetIn(document.getElementById('restored-by-yes'));
    var frames = frameset.querySelectorAll('frame');
    shouldBe('frames[0].offsetWidth', offWidth);
    frameset.setAttribute('frameborder', 'yes');
    shouldBe('frames[0].offsetWidth', onWidth);
    shouldBe('frames[1].offsetWidth', onWidth);
    debug('<br>');

    debug('Removing the frameborder attribute restores the default (true), not false:');
    frameset = framesetIn(document.getElementById('restored-by-removal'));
    frames = frameset.querySelectorAll('frame');
    shouldBe('frames[0].offsetWidth', offWidth);
    frameset.removeAttribute('frameborder');
    shouldBe('frames[0].offsetWidth', onWidth);
    shouldBe('frames[1].offsetWidth', onWidth);
    debug('<br>');
</script>