chromium/third_party/blink/web_tests/external/wpt/css/css-backgrounds/border-radius-dynamic-from-no-radius.html

<!doctype html>
<html class="reftest-wait">
<title>CSS Test: Relative dynamic border-radius change</title>
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:[email protected]">
<link rel="author" title="Mozilla" href="https://mozilla.org">
<link rel="help" href="https://drafts.csswg.org/css-backgrounds/#border-radius">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1554755">
<link rel="match" href="border-radius-dynamic-from-no-radius-ref.html">
<style>
  #outer {
    width: 100px;
    height: 100px;
  }
  #inner {
    width: 100%;
    height: 100%;
    background: green;
    /* The key is that this starts off computing to zero */
    border-radius: calc(100% - 1px);
  }
</style>
<p>Should be a green circle below</p>
<div id="outer" style="width: 1px; height: 1px;">
  <div id="inner"></div>
</div>
<script>
onload = function() {
  requestAnimationFrame(function() {
    requestAnimationFrame(function() {
      outer.style.height = "";
      outer.style.width = "";
      document.documentElement.className = "";
    });
  });
}
</script>