| Index: third_party/WebKit/LayoutTests/fast/layout/scroll-anchoring/feedback-loop.html
|
| diff --git a/third_party/WebKit/LayoutTests/fast/layout/scroll-anchoring/feedback-loop.html b/third_party/WebKit/LayoutTests/fast/layout/scroll-anchoring/feedback-loop.html
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..2bfe126d2c264769398928f19f913f217f593c61
|
| --- /dev/null
|
| +++ b/third_party/WebKit/LayoutTests/fast/layout/scroll-anchoring/feedback-loop.html
|
| @@ -0,0 +1,53 @@
|
| +<!DOCTYPE html>
|
| +<script src="../../../resources/testharness.js"></script>
|
| +<script src="../../../resources/testharnessreport.js"></script>
|
| +<style>
|
| +
|
| +body { margin: 0; height: 5000px; }
|
| +#evil { height: 200px; width: 200px; background-color: #fcc; }
|
| +
|
| +</style>
|
| +<div id="evil"></div>
|
| +<script>
|
| +
|
| +internals.runtimeFlags.scrollAnchoringEnabled = true;
|
| +
|
| +var kMaxAdjustments = 20; // Keep in sync with kMaxAdjustments in ScrollAnchor.cpp
|
| +
|
| +var evil = document.querySelector('#evil');
|
| +onscroll = () => { evil.style.marginTop = scrollY + "px"; };
|
| +
|
| +var frame = () => new Promise((resolve) => { requestAnimationFrame(resolve); });
|
| +
|
| +var waitFor = function(condition, failmsg, deadline) {
|
| + if (!deadline) deadline = Date.now() + 1000;
|
| + if (condition()) return Promise.resolve();
|
| + else if (Date.now() > deadline) return Promise.reject(failmsg);
|
| + else return frame().then(() => waitFor(condition, failmsg, deadline));
|
| +};
|
| +
|
| +var waitFrames = function(n, condition, failmsg) {
|
| + var p = Promise.resolve();
|
| + var check = () => (!condition || condition() ?
|
| + Promise.resolve() : Promise.reject(failmsg));
|
| + while (n--)
|
| + p = p.then(check).then(frame);
|
| + return p.then(check);
|
| +};
|
| +
|
| +var scrollSettlesAt = function(expectedY) {
|
| + return waitFor(() => (scrollY == expectedY),
|
| + "scroll did not reach " + expectedY)
|
| + .then(() => waitFrames(3))
|
| + .then(() => waitFrames(3, () => (scrollY == expectedY),
|
| + "scroll did not stay at " + expectedY));
|
| +};
|
| +
|
| +promise_test(function() {
|
| + var y = 10;
|
| + return Promise.resolve()
|
| + .then(() => { scrollTo(0, y); })
|
| + .then(() => scrollSettlesAt(y + kMaxAdjustments * y));
|
| +}, "Scroll anchoring with scroll event handler feedback loop");
|
| +
|
| +</script>
|
|
|
Chromium Code Reviews
Issue 2118683002:
Limit ScrollAnchor to 20 adjustments between user scrolls. (Closed)
Base URL: https://chromium.googlesource.com/chromium/src.git@master