Magic-Mirror/gecko-dev
1
0
Fork 0
mirror of https://github.com/mozilla/gecko-dev.git synced 2024-10-10 11:55:49 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Bug 1291413 - Fix assertion when resuming an Animation with both a start time and hold time; r=hiro

Browse Source 
When we set the playback rate to zero on a play-pending animation that is
resuming from an aborted pause we can arrive in a state where both the start
time and hold time are resolved. However, we previously added an assertion that
only one of these is ever set at a time.

Part of the assertion is warranted since that method contains the following
code:

  if (mStartTime.IsNull()) {
    mStartTime = StartTimeFromReadyTime(aReadyTime);
    if (mPlaybackRate != 0) {
      mHoldTime.SetNull();
    }
  }

Here StartTimeFromReadyTime requires a non-null hold time. So either mStartTime
or mHoldTime needs to be non-null. The requirement that only one or the other be
non-null, however, is not in the spec and not necessary (as the test cases in
this bug show).

What this assertion does bring to light, however, is that in the case where we
have *both* the start time and the hold time, we need to consider whether to use
the start time as-is, or calculate it from the hold time.

I have filed the following spec issue for this:

  https://github.com/w3c/web-animations/issues/200



MozReview-Commit-ID: CTCT7Up1E5n

--HG--
extra : rebase_source : 95233f7cd2bc3c4bcc56615d8387fe54852986c1
This commit is contained in:
Brian Birtles 2017-10-05 10:50:38 +09:00
parent 7c9ee7c537
commit 3afa921d85
4 changed files with 45 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
dom/animation/Animation.cpp
View File

@ -1188,9 +1188,9 @@ Animation::ResumeAt(const TimeDuration& aReadyTime)
// but it's currently not necessary.
MOZ_ASSERT(mPendingState == PendingState::PlayPending,
"Expected to resume a play-pending animation");
MOZ_ASSERT(mHoldTime.IsNull() != mStartTime.IsNull(),
MOZ_ASSERT(!mHoldTime.IsNull() || !mStartTime.IsNull(),
"An animation in the play-pending state should have either a"
" resolved hold time or resolved start time (but not both)");
" resolved hold time or resolved start time");
// If we aborted a pending pause operation we will already have a start time
// we should use. In all other cases, we resolve it from the ready time.

20
dom/animation/test/crashtests/1291413-1.html Normal file
View File

@ -0,0 +1,20 @@
<!doctype html>
<html class=reftest-wait>
<script>
window.onload = () => {
const div = document.createElement('div');
document.documentElement.appendChild(div);
const anim = div.animate([], 1000);
anim.ready.then(() => {
anim.pause();
anim.reverse();
anim.playbackRate = 0;
anim.ready.then(() => {
document.documentElement.className = '';
});
});
};
</script>
</html>

21
dom/animation/test/crashtests/1291413-2.html Normal file
View File

@ -0,0 +1,21 @@
<!doctype html>
<html class=reftest-wait>
<script>
window.onload = () => {
const div = document.createElement('div');
document.documentElement.appendChild(div);
const anim = div.animate([], 1000);
anim.ready.then(() => {
anim.pause();
anim.reverse();
anim.playbackRate = 0;
anim.playbackRate = 1;
anim.ready.then(() => {
document.documentElement.className = '';
});
});
};
</script>
</html>

2
dom/animation/test/crashtests/crashtests.list
View File

@ -10,6 +10,8 @@ pref(dom.animations-api.core.enabled,true) load 1272475-1.html
pref(dom.animations-api.core.enabled,true) load 1272475-2.html
pref(dom.animations-api.core.enabled,true) load 1278485-1.html
pref(dom.animations-api.core.enabled,true) load 1277272-1.html
pref(dom.animations-api.core.enabled,true) load 1291413-1.html
pref(dom.animations-api.core.enabled,true) load 1291413-2.html
pref(dom.animations-api.core.enabled,true) load 1304886-1.html
pref(dom.animations-api.core.enabled,true) load 1322382-1.html
pref(dom.animations-api.core.enabled,true) load 1322291-1.html