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<!DOCTYPE html>
<html>
<meta name="viewport" content="width=device-width; initial-scale=1.0">
<title>Test that preventDefault() in a dynamically-added touchmove listener prevents scrolling</title>
<script src="/tests/SimpleTest/SimpleTest.js"></script>
<script src="/tests/SimpleTest/paint_listener.js"></script>
<script src="apz_test_utils.js"></script>
<script src="apz_test_native_event_utils.js"></script>
<div style="height: 500vh;"></div>
<script>
async function test() {
// A passive touchstart listener dynamically adds an active touchmove
// listener that calls preventDefault(). APZ must re-hit-test on the first
// touchmove to discover the new listener and wait for a content response,
// so that the preventDefault() is respected and scrolling is suppressed.
const touchstartPromise = new Promise(resolve => {
window.addEventListener("touchstart", () => {
document.addEventListener("touchmove", e => {
e.preventDefault();
}, { passive: false, once: true });
resolve();
}, { passive: true, once: true });
});
await promiseApzFlushedRepaints();
await synthesizeNativeTouch(window, 100, 200,
SpecialPowers.DOMWindowUtils.TOUCH_CONTACT);
await touchstartPromise;
// Though as of now fast-path notifiction explicitly schedules a paint,
// it will not in future, so wait two requestAnimationFrames rather than
// waiting for a paint.
await promiseFrame();
await promiseFrame();
await synthesizeNativeTouch(window, 100, 150,
SpecialPowers.DOMWindowUtils.TOUCH_CONTACT);
await synthesizeNativeTouch(window, 100, 100,
SpecialPowers.DOMWindowUtils.TOUCH_CONTACT);
await synthesizeNativeTouch(window, 100, 100,
SpecialPowers.DOMWindowUtils.TOUCH_REMOVE);
await promiseApzFlushedRepaints();
is(window.scrollY, 0, "Should not have scrolled");
}
waitUntilApzStable()
.then(test)
.then(subtestDone, subtestFailed);
</script>
</html>