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<meta charset="utf-8">
<meta name="viewport" content="width=device-width; initial-scale=1.0">
<title>Sanity panning test</title>
<script type="application/javascript" src="apz_test_native_event_utils.js"></script>
<script type="application/javascript" src="apz_test_utils.js"></script>
<script src="/tests/SimpleTest/paint_listener.js"></script>
<script src="/tests/SimpleTest/EventUtils.js"></script>
<script type="application/javascript">
async function test() {
let scrEvt = new EventCounter(window, "scroll");
let visScrEvt = new EventCounter(window.visualViewport, "scroll");
// Our internal visual viewport events aren't restricted to the visual view-
// port itself, so we can listen on the window itself, however the event
// listener needs to be in the system group.
let visScrEvtInternal = new EventCounter(window, "mozvisualscroll",
{ mozSystemGroup: true });
// This listener will trigger the test to continue once APZ is done with
// processing the scroll.
let transformEndPromise = promiseTransformEnd();
await synthesizeNativeTouchDrag(document.body, 10, 100, 0, -50);
dump("Finished native drag, waiting for transform-end observer...\n");
// Wait for the APZ:TransformEnd to be fired after touch events are processed.
await transformEndPromise;
// Flush state.
await promiseApzFlushedRepaints();
is(window.scrollY, 50, "check that the window scrolled");
// Check we've got the expected events.
// This page is using "width=device-width; initial-scale=1.0" and we haven't
// pinch-zoomed any further, so layout and visual viewports have the same
// size and will scroll together. Therefore we should be getting layout
// viewport "scroll" events as well.
ok(scrEvt.count > 0, "Got some layout viewport scroll events");
// This one is a bit tricky: Visual viewport "scroll" events are supposed to
// fire only when the relative offset between layout and visual viewport
// changes. Even when they're both scrolling together, we may update their
// positions independently, though, leading to some jitter in the offset and
// triggering the event after all.
// At least for the case here, where both viewports are the same size and we
// have a freshly loaded page, we should however be able to keep the offset at
// a constant zero and therefore not cause any visual viewport scroll events
// to fire.
is(visScrEvt.count, 0, "Got no visual viewport scroll events");
// Our internal visual viewport scroll event on the other hand only cares
// about the absolute offset of the visual viewport and should therefore
// definitively fire.
ok(visScrEvtInternal.count > 0, "Got some mozvisualscroll events");
.then(subtestDone, subtestFailed);
<div style="height: 5000px; background-color: lightgreen;">
This div makes the page scrollable.