chromium/third_party/blink/web_tests/external/wpt/scroll-to-text-fragment/percent-encoding.html

<!DOCTYPE html>
<title>Percent-encoding in a text directive</title>
<meta charset=utf-8>
<link rel="help" href="https://wicg.github.io/ScrollToTextFragment/">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="resources/util.js"></script>
<style>
  .target {
    margin-top: 2000px;
    margin-bottom: 2000px;
  }
</style>
<script>

function determineResult() {
  if (window.scrollY == 0)
    return 'noscroll';

  for (let target of document.querySelectorAll('.target')) {
    if (isInViewport(target)) {
      return target.id;
    }
  }
  return 'UNEXPECTED';
}

let test_cases = [
  {
    fragment: '#:~:text=%25',
    expect: 'singlepercent',
    description: 'Percent-encoded "%" char.'
  },
  {
    fragment: '#:~:text=%',
    expect: 'singlepercent',
    description: 'Percent char without hex digits is invalid.'
  },
  {
    fragment: '#:~:text=%%',
    expect: 'doublepercent',
    description: 'Percent char followed by percent char is invalid.'
  },
  {
    fragment: '#:~:text=%F',
    expect: 'percentf',
    description: 'Single digit percent-encoding is invalid.'
  },
  {
    fragment: '#:~:text=%25F',
    expect: 'percentf',
    description: 'Percent-encoding limited to two digits.'
  },
  {
    fragment: '#:~:text=%25%25F',
    expect: 'doublepercentf',
    description: 'Percent-encoded "%%F"'
  },
  {
    fragment: '#:~:text=%E2%9C%85',
    expect: 'checkmark',
    description: 'Percent-encoding multibyte codepoint (CHECKMARK).'
  },
];

function runTests()  {
  for (const test_case of test_cases) {
    promise_test(t => new Promise(resolve => {
      // Clear the fragment and reset the scroll offset to prepare for the next
      // test case.
      location = `${location.pathname}#`;
      scrollTo(0, 0);

      location = `${location.pathname}${test_case.fragment}`;
      requestAnimationFrame( () => requestAnimationFrame(resolve) );
    }).then(() => {
      assert_equals(determineResult(), test_case.expect);
    }), `Test navigation with fragment: ${test_case.description}.`);
  }
}
</script>
<body onload="runTests()">
<p class="target" id="singlepercent">
  %
</p>
<p class="target" id="doublepercent">
  %%
</p>
<p class="target" id="percentf">
  %F
</p>
<p class="target" id="doublepercentf">
  %%f
</p>
<p class="target" id="checkmark">
  <!-- U+2705 WHITE HEAVY CHECK MARK - UTF-8 percent encoding: %E2%9C%85 -->
  &#x2705;
</p>
<p class="target" id="helloworld">
  Hello world
</p>

</body>