css/css-scroll-snap/selection-target.html

<!doctype html>
<meta charset=utf-8>
<title>scroll-padding is respected when typing into an out-of-view textfield</title>
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1701928">
<link rel="help" href="https://drafts.csswg.org/css-scroll-snap/#scroll-padding">
<link rel="author" href="mailto:emilio@crisal.io" title="Emilio Cobos Álvarez">
<link rel="author" href="https://mozilla.org" title="Mozilla">
<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/testdriver-actions.js"></script>
<style>
  body {
    margin: 0;
  }
  :root {
    scroll-padding-top: 100px;
  }
</style>
<div style="height: 300vh;"></div>
<input type="text">
<div style="height: 300vh;"></div>
<script>
function tick() {
  return new Promise(resolve => {
    requestAnimationFrame(() => requestAnimationFrame(resolve));
  });
}

promise_test(async function() {
  let input = document.querySelector("input");
  input.focus();
  await tick();
  // Scroll out of view.
  scrollTo(0, document.scrollingElement.scrollHeight);
  await tick();
  assert_not_equals(window.scrollY, 0);
  assert_true(input.getBoundingClientRect().bottom < 0, "Should be offscreen");
  // NOTE(emilio): Using test_driver.Actions() instead of test_driver.send_keys
  // because the later scrolls the target into view which would defeat the
  // point of the test...
  await new test_driver.Actions().keyDown('a').send();
  await tick();
  // We assert the bottom rather than the top because Gecko scrolls the
  // selection bounds into view, not the whole input.
  assert_true(input.getBoundingClientRect().bottom > 100, "Scroll-padding should be respected");
}, "Test scrolling into view when typing");
</script>