chromium/third_party/blink/web_tests/external/wpt/css/css-flexbox/radiobutton-min-size.html

<!DOCTYPE html>
<title>CSS Flexbox: minimum size of the radio button</title>
<link rel="help" href="https://drafts.csswg.org/css-flexbox/#flex-property">
<link rel="help" href="https://drafts.csswg.org/css-flexbox/#min-size-auto">
<meta name="assert" content="This test ensures that radio buttons used as flex items do not shrink below their default sizes.">
<style>
.flex {
  display: flex;
  width: 500px;
}

.wide {
  width: 600px;
  flex: none;
}
</style>

<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<p>You should see two identical-looking lines, both with a radio button at the
beginning.</p>

<div class="flex">
  <input type="radio" id="check">
  <div class="wide">Text</div>
</div>

<div>
  <input type="radio" style="vertical-align: top;" id="ref"><span>Text</span>
</div>

<script>
var ref = document.getElementById("ref");
var check = document.getElementById("check");

test(function() {
  assert_equals(ref.offsetWidth, check.offsetWidth, "width should be equal");
}, "two radio button widths are identical");
</script>