author James Teh <>
Wed, 01 Feb 2023 05:02:01 +0000
changeset 651150 dd0fdd1daa69783be36acd5c50544f3694eaa8f9
parent 566266 aafff593562887152fdabcd62ff55dd23630bf4e
permissions -rw-r--r--
Bug 1813980: Check IsDoc before Parent in RemoteAccessibleBase::ApplyCrossDocOffset. r=morgan We call this function on every ancestor when calculating bounds. RemoteParent() currently requires a hash lookup, so it's more efficient to early return for !IsDoc() first. This is a micro-optimisation, but it might have some impact given that we call this on every ancestor, especially when hit testing, where we call Bounds() a lot. As a bit of drive-by cleanup, use RemoteParent() rather than calling Parent() and IsRemote/AsRemote(). Differential Revision:

  <meta charset="utf-8">
  <title>Ensure positioned content inside inactive scollframes but on top of OOPIFs hit-test properly</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <script src="/tests/SimpleTest/paint_listener.js"></script>
  <script src="helper_fission_utils.js"></script>
  <script src="apz_test_utils.js"></script>
  <script src="apz_test_native_event_utils.js"></script>


  .then(loadOOPIFrame("testframe", "helper_fission_empty.html"))
  .then(FissionTestHelper.subtestDone, FissionTestHelper.subtestFailed);

let make_oopif_scrollable = function() {
  // ensure the oopif is scrollable, and wait for the paint so that the
  // compositor also knows it's scrollable. = "200vh";
  promiseApzFlushedRepaints().then(() => {
    let utils = SpecialPowers.getDOMWindowUtils(window);
    let result = {
      layersId: utils.getLayersId(),
      viewId: utils.getViewId(document.scrollingElement)
    dump(`OOPIF computed IDs ${JSON.stringify(result)}\n`);
    FissionTestHelper.fireEventInEmbedder("OOPIF:Scrollable", result);
  return true;

async function test() {
  let iframe = document.getElementById("testframe");

  let oopifScrollerIdsPromise = promiseOneEvent(window, "OOPIF:Scrollable", null);
  ok(await FissionTestHelper.sendToOopif(iframe, `(${make_oopif_scrollable})()`),
     "Ran code to make OOPIF scrollable");
  let oopifScrollerIds = (await oopifScrollerIdsPromise).data;

  let config = getHitTestConfig();
  let utils = config.utils;

  // The #scroller div is (a) inactive, and (b) under the OOPIF. However, it
  // also contains a positioned element with a high z-index (#abspos). #abspos
  // therefore sits on top of the OOPIF. Hit-testing on #abspos should hit
  // #scroller, but anywhere else within the OOPIF box should hit the OOPIF.

  checkHitResult(await fissionHitTest(centerOf("abspos"), iframe),
                 APZHitResultFlags.VISIBLE |
                 (config.activateAllScrollFrames ? 0 : APZHitResultFlags.INACTIVE_SCROLLFRAME),
                 config.activateAllScrollFrames ?
                   utils.getViewId(document.getElementById("scroller")) :
                 "abspos element on top of OOPIF should hit parent doc hosting the OOPIF");

  // If the fix for the bug this test is for is not active (as indicated by
  // config.activateAllScrollFrames) then we just accept the wrong answer. As
  // of writing this comment the fix will only be active if fission is pref'ed
  // on, not just enabled for this window, ie the test suite is run in fission
  // mode.
  checkHitResult(await fissionHitTest(centerOf("scroller"), iframe),
                 APZHitResultFlags.VISIBLE |
                 (config.activateAllScrollFrames ? 0 : APZHitResultFlags.INACTIVE_SCROLLFRAME),
                 config.activateAllScrollFrames ?
                   oopifScrollerIds.viewId :
                 config.activateAllScrollFrames ?
                   oopifScrollerIds.layersId :
                 "Part of OOPIF sitting on top of the inactive scrollframe should hit OOPIF");

  checkHitResult(await fissionHitTest({x: 250, y: 100}, iframe),
                 "part of OOPIF outside the inactive scfollframe rect should hit the OOPIF");

html, body {
    margin: 0;
body {
    /* Ensure root document is scrollable so that #scroller is inactive by
      default */
    height: 200vh;
iframe {
    position: absolute;
    width: 300px;
    height: 200px;

#scroller {
    position: absolute;
    top: 0;
    left: 0;
    width: 200px;
    height: 200px;
    background-color: transparent;
    overflow-y: scroll;
<div id="scroller">
  <div style="height:500px">inside scroller</div>
  <div id="abspos" style="position: absolute; z-index: 5; left: 0; width: 80px; top: 20px; height: 80px; background-color: green">abspos inside scroller</div>
<iframe id="testframe"></iframe>