author James Teh <>
Wed, 01 Feb 2023 05:02:01 +0000
changeset 651150 dd0fdd1daa69783be36acd5c50544f3694eaa8f9
parent 589289 7e795e95ddda3f9b8fb6fe4cff9077834f8b898e
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">
  <meta name="viewport" content="width=device-width, minimum-scale=1.0">
  <title>Tests that zooming out with an unchanging scroll pos still works properly</title>
  <script src="/tests/SimpleTest/EventUtils.js"></script>
  <script type="application/javascript" src="apz_test_utils.js"></script>
  <script type="application/javascript" src="apz_test_native_event_utils.js"></script>
  <script src="/tests/SimpleTest/paint_listener.js"></script>
  <div style="height: 2000px; background-color: linear-gradient(green,blue)"></div>
  <script type="application/javascript">
    const utils = SpecialPowers.getDOMWindowUtils(window);

    async function test() {
      // Initial state
      is(await getResolution(), 1.0, "should not be zoomed");

      // Zoom in
      await promiseApzFlushedRepaints();
      // Check that we're still at 0,0 in both layout and visual viewport
      is(await getResolution(), 2.0, "should be zoomed to 2.0");
      is(window.scrollX, 0, "shouldn't have scrolled (1)");
      is(window.scrollY, 0, "shouldn't have scrolled (2)");
      is(visualViewport.pageLeft, 0, "shouldn't have scrolled (3)");
      is(visualViewport.pageTop, 0, "shouldn't have scrolled (4)");

      // Freeze the main-thread refresh driver to stop it from processing
      // paint requests

      // Zoom out. This will send a series of paint requests to the main
      // thread with zooms that go down from 2.0 to 1.0.
      // Use a similar touch sequence to what pinchZoomOutWithTouchAtCenter()
      // does, except keep the first touch point anchored and only move the
      // second touch point. In particular, we drag the second touch point
      // from the top-left quadrant of the screen to the bottom-right, so that
      // the scroll position never changes from 0,0. If we move either finger
      // upwards at all, the synthesization can generate intermediate touch
      // events with just that change which can cause the page to scroll down
      // which we don't want here.
      // The key here is that each of the repaint requests keeps the scroll
      // position at 0,0, which in terms of the bug, means that only the first
      // repaint request actually takes effect and the rest are discarded.
      // The first repaint request has a zoom somewhere between 1.0 and 2.0,
      // and therefore after the pinch is done, the zoom ends up stuck there
      // instead of going all the way back to 1.0 like we would expect.
      const deltaX = window.visualViewport.width / 16;
      const deltaY = window.visualViewport.height / 16;
      const centerX =
        window.visualViewport.pageLeft + window.visualViewport.width / 2;
      const centerY =
        window.visualViewport.pageTop + window.visualViewport.height / 2;
      const anchorFinger = { x: centerX + (deltaX * 6), y: centerY + (deltaY * 6) };
      var zoom_out = [];
      for (var i = -6; i < 6; i++) {
        var movingFinger = { x: centerX + (deltaX * i), y: centerY + (deltaY * i) };
        zoom_out.push([anchorFinger, movingFinger]);
      var touchIds = [0, 1];
      await synthesizeNativeTouchAndWaitForTransformEnd(zoom_out, touchIds);

      // Release the refresh driver

      // Flush all the things, reach stable state
      await promiseApzFlushedRepaints();

      // Check that we're back at 1.0 resolution
      is(await getResolution(), 1.0, "should be back at initial resolution");

      // More sanity checks
      is(window.scrollX, 0, "shouldn't have scrolled (5)");
      is(window.scrollY, 0, "shouldn't have scrolled (6)");
      is(visualViewport.pageLeft, 0, "shouldn't have scrolled (7)");
      is(visualViewport.pageTop, 0, "shouldn't have scrolled (8)");

    waitUntilApzStable().then(test).then(subtestDone, subtestFailed);