helper_tab_scroll_scrollIntoView.html

Enable keyboard shortcuts

<!DOCTYPE html>

<html>

<head>

  <meta charset="utf-8">

  <script src="apz_test_utils.js"></script>

  <script src="apz_test_native_event_utils.js"></script>

  <script src="/tests/SimpleTest/EventUtils.js"></script>

  <script src="/tests/SimpleTest/paint_listener.js"></script>

  <style>

.spacer {

  height: 200vh;

  width: 100%;

  background: green;

#target {

  height: 5vh;

  width: 100%;

  background: red;

  </style>

</head>

<body>

  <div class="spacer"></div>

  <button id="target"></button>

  <div class="spacer"></div>

</body>

<script>

async function test() {

  let scrollendPromise = promiseScrollend();

  window.synthesizeKey("KEY_Tab");

  await scrollendPromise;

  let tabScrollPosition = document.scrollingElement.scrollTop;

  target.scrollIntoView({block: "center", inline: "center"});

  let scrollIntoViewPosition = document.scrollingElement.scrollTop;

  // The scroll position after an explicit scrollIntoView call on the target

  // with block and inline set to "center" should be within +/- 1 of the

  // scroll position from the tab scroll.

  ok(tabScrollPosition >= scrollIntoViewPosition - 1 &&

     tabScrollPosition <= scrollIntoViewPosition + 1,

     "target element should be centered by tab scroll");

waitUntilApzStable()

.then(test)

.then(subtestDone, subtestFailed);

</script>

</html>