chromium/third_party/blink/web_tests/external/wpt/css/css-scroll-snap/snap-on-focus.html

<!DOCTYPE html>
<title>Scroll snap on Element.focus()</title>
<link rel="help" href="https://drafts.csswg.org/css-scroll-snap/" />
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
div {
  position: absolute;
  margin: 0;
}

#scroller {
  height: 500px;
  width: 500px;
  overflow-y: scroll;
  scroll-snap-type: y mandatory;
}

.snap {
  width: 100%;
  height: 300px;
  top: 100px;
  left: 0;
  background-color: green;
  scroll-snap-align: start none;
}

.no-snap {
  width: 100%;
  height: 300px;
  top: 100px;
  left: 0;
  background-color: red;
}

.area {
  width: 100%;
  height: 2000px;
}
</style>

<div id="scroller">
  <div class="area"></div>
  <div class="snap" style="top: 0px;"></div>
  <div class="no-snap" style="top: 1000px;" tabindex=-1></div>
  <div class="snap" style="top: 1200px;"></div>
</div>

<script>
promise_test(async () => {
  document.querySelector(".no-snap").focus();
  await new Promise(resolve => step_timeout(resolve, 0));
  assert_equals(scroller.scrollTop, 1200);
}, "scroll snap should happens on Element.focus()");

</script>