<!DOCTYPE html>
<html>
<title>View transitions: duplicate tags in the new DOM skip the transition</title>
<link rel="help" href="https://www.w3.org/TR/css-view-transitions-1/">
<link rel="author" href="mailto:[email protected]">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
div {
width: 100px;
height: 100px;
background: blue;
contain: paint;
}
</style>
<div id=first></div>
<div id=second></div>
<script>
promise_test(async t => {
assert_implements(document.startViewTransition, "Missing document.startViewTransition");
return new Promise((resolve, reject) => {
first.style = "view-transition-name: target";
let transition = document.startViewTransition(() => {
first.style = "view-transition-name: target";
second.style = "view-transition-name: target";
});
// First updateCallbackDone resolves since the callback runs successfully.
let updateCallbackDoneResolved = false;
transition.updateCallbackDone.then(() => { updateCallbackDoneResolved = true; }, reject);
// Ready rejects.
let readyRejected = false;
transition.ready.then(reject, () => {
readyRejected = true;
assert_true(updateCallbackDoneResolved, "updateCallbackDone should resolve before ready was rejected");
});
// Then finished resolves since updateCallbackDone was already resolved.
transition.finished.then(() => {
assert_true(readyRejected, "finished should resolve after ready was rejected");
resolve();
}, reject);
});
}, "Two different elements with the same name in the new DOM should skip the transition");
</script>