<!DOCTYPE HTML>
<meta charset=utf-8>
<title>Long Animation Frame Timing: basic</title>
<meta name="timeout" content="long">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/utils.js"></script>
<body>
<h1>Long Animation Frame: basic</h1>
<div id="log"></div>
<script>
promise_test(async t => {
await expect_long_frame(() => busy_wait(), t);
}, 'A long busy wait is a long animation frame');
promise_test(async t => {
await expect_long_frame(() => requestAnimationFrame(busy_wait), t);
}, 'A long busy wait in a requestAnimationFrame is a long animation frame');
promise_test(async t => {
const segment_duration = very_long_frame_duration / 2;
const entry = await expect_long_frame(async () => {
busy_wait(segment_duration);
await new Promise(resolve => requestAnimationFrame(() => {
busy_wait(segment_duration)
resolve();
}));
}, t);
assert_not_equals(entry, "timeout");
assert_greater_than_equal(entry.renderStart - entry.startTime, segment_duration);
}, 'A long busy wait split between a task and a requestAnimationFrame is a long animation frame');
promise_test(async t => {
const segment_duration = very_long_frame_duration / 3;
const entry = await expect_long_frame(async () => {
const element = document.createElement("div");
document.body.appendChild(element);
t.add_cleanup(() => element.remove());
busy_wait(segment_duration);
requestAnimationFrame(() => {
busy_wait(segment_duration);
});
new ResizeObserver(() => {
busy_wait(segment_duration);
}).observe(element);
}, t);
assert_not_equals(entry, "timeout");
assert_greater_than_equal(entry.renderStart - entry.startTime, segment_duration);
assert_greater_than_equal(entry.styleAndLayoutStart - entry.renderStart, segment_duration);
}, 'ResizeObservers should create a long-frame and affect layoutStartTime');
</script>
</body>
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