chromium/third_party/blink/web_tests/external/wpt/trusted-types/trusted-types-duplicate-names.html

<!DOCTYPE html>
<head>
  <script src="/resources/testharness.js"></script>
  <script src="/resources/testharnessreport.js"></script>
  <meta http-equiv="Content-Security-Policy"
        content="trusted-types 'allow-duplicates' duplicatename default">
</head>
<body>
<script>
test(t => {
  // We expect neither of these to throw.
  let a = trustedTypes.createPolicy("duplicatename", { createHTML: _ => "a" });
  let b = trustedTypes.createPolicy("duplicatename", { createHTML: _ => "b" });

  // Both should have worked. They should still be separate functions.
  assert_not_equals(a, b);
  assert_equals("" + a.createHTML(""), "a");
  assert_equals("" + b.createHTML(""), "b");

  let def = trustedTypes.createPolicy("default", {});
  assert_throws_js(TypeError,
                   _ => trustedTypes.createPolicy("default", {}));
}, "policy - duplicate names");
</script>
</body>