<!DOCTYPE html>
<html>
<body>
<script src="../../resources/js-test-pre.js"></script>
<script>
description("Tests support for 'once' member in AddEventListenerOptions.");

var listenerCallCount = 0;
function listenerFunction()
{
    ++listenerCallCount;
}

evalAndLog("document.body.addEventListener('test', listenerFunction, { 'once': true })");
shouldBe("listenerCallCount", "0");
evalAndLog("document.body.dispatchEvent(new Event('test'))");
shouldBe("listenerCallCount", "1");
evalAndLog("document.body.dispatchEvent(new Event('test'))");
shouldBe("listenerCallCount", "1");

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