chromium/third_party/blink/web_tests/external/wpt/html/semantics/forms/the-selectlist-element/selectlist-required-attribute.tentative.html

<!DOCTYPE html>
<html lang="en">
<title>HTMLSelectListElement Test: required attribute</title>
<link rel="author" title="Ionel Popescu" href="mailto:[email protected]">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<style>
  selectlist:required {
    border: 3px dashed rgb(255, 0, 0);
  }

  selectlist:optional {
    border: 1px solid rgb(128, 128, 128);
  }
</style>

<selectlist id="selectlist0" required>
  <option>one</option>
  <option>two</option>
  <option>three</option>
</selectlist>

<selectlist id="selectlist1">
  <option>one</option>
  <option>two</option>
  <option>three</option>
</selectlist>

<selectlist id="selectlist2">
  <option>one</option>
  <option>two</option>
  <option>three</option>
</selectlist>

<script>
function checkRequired(style) {
  assert_equals(style.borderWidth, '3px');
  assert_equals(style.borderStyle, 'dashed');
  assert_equals(style.borderColor, 'rgb(255, 0, 0)');
}

function checkOptional(style) {
  assert_equals(style.borderWidth, '1px');
  assert_equals(style.borderStyle, 'solid');
  assert_equals(style.borderColor, 'rgb(128, 128, 128)');
}

test(() => {
  const selectList0 = document.getElementById("selectlist0");
  const selectList1 = document.getElementById("selectlist1");
  const selectList2 = document.getElementById("selectlist2");

  checkRequired(window.getComputedStyle(selectList0));
  checkOptional(window.getComputedStyle(selectList1));
  checkOptional(window.getComputedStyle(selectList2));
  selectList2.required = true;
  checkRequired(window.getComputedStyle(selectList2));
}, "Test required attribute");

</script>