chromium/third_party/blink/web_tests/external/wpt/css/css-view-transitions/set-current-time-transform.html

<!DOCTYPE html>
<html class=reftest-wait>
<title>View transitions: set current time</title>
<link rel="help" href="https://www.w3.org/TR/css-view-transitions-1/">
<link rel="author" href="mailto:[email protected]">
<link rel="match" href="set-current-time-transform-ref.html">
<script src="/common/reftest-wait.js"></script>
<style>
:root { view-transition-name: unset; }
#target {
  width: 100px;
  height: 100px;
  background: blue;
  view-transition-name: target;
  position: relative;
}
.left {
  left: 0;
}
.right {
  left: 100px;
}

html::view-transition-group(*) {
  animation: unset;
}
html::view-transition-old(*) {
  animation: unset;
  opacity: 0;
}
@keyframes move {
  from {
    transform: translate(500px);
  }
}
html::view-transition-new(target) {
  animation-name: move;
  animation-duration: 1s;
  animation-timing-function: linear;
  animation-play-state: paused;
}
</style>

<div id=target class=left></div>

<script>
failIfNot(document.startViewTransition, "Missing document.startViewTransition");

async function runTest() {
  let transition = document.startViewTransition(() => target.classList.replace("left", "right"));
  transition.ready.then(() => {
    requestAnimationFrame(() => requestAnimationFrame(() => {
      document.getAnimations().forEach((animation) => {
        animation.currentTime = 500;
      });
      requestAnimationFrame(takeScreenshot);
    }));
  });
}
onload = () => requestAnimationFrame(() => requestAnimationFrame(runTest));
</script>