helper_override_root.html

Enable keyboard shortcuts

<!DOCTYPE HTML>

<html>

<head>

  <meta charset="utf-8">

  <meta name="viewport" content="width=device-width; initial-scale=1.0">

  <title>Simple wheel scroll cancellation</title>

  <script type="application/javascript" src="apz_test_native_event_utils.js"></script>

  <script type="application/javascript" src="apz_test_utils.js"></script>

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

  <script type="application/javascript">

async function test() {

  let wheelEventPromise = new Promise(resolve => {

    // Add a non-passive listener on the document, so that we have a document-level

    // APZ-aware listener, and the entire document is put in the dispatch-to-content

    // region

    document.addEventListener("wheel", function(e) {

      // spin for 2 seconds to give APZ time to scroll, if the event region override

      // is broken and it decides not to wait for the main thread. Note that it's

      // possible the APZ controller thread is busy for whatever reason so APZ

      // may not scroll. That might cause this test to only fail intermittently

      // instead of consistently if the behaviour being tested regresses.

      var now = Date.now();

      while (Date.now() - now < 2000);

      // Cancel the scroll. If this works then we know APZ waited for this listener

      // to run.

      e.preventDefault();

      resolve()

    }, { passive: false });

});

  // Ensure APZ gets a paint with the d-t-c region

  await promiseApzFlushedRepaints();

  await synthesizeNativeWheel(document.body, 100, 100, 0, -50);

  dump("Finished native wheel, waiting for listener to run...\n");

  await wheelEventPromise;

  await promiseOnlyApzControllerFlushed();

  is(window.scrollY, 0, "check that the window didn't scroll");

if (window.top != window) {

    dump("Running inside an iframe! stealing functions from window.top...\n");

    window.subtestDone = window.top.subtestDone;

    window.SimpleTest = window.top.SimpleTest;

    window.is = window.top.is;

    window.ok = window.top.ok;

waitUntilApzStable()

  .then(test)

  .then(subtestDone);

  </script>

</head>

<body style="height: 5000px; background-image: linear-gradient(green,red);">

  This page should not be wheel-scrollable.

</body>

</html>