1333062 - Play button breaks if I drag scrubber to the right twice

Status: RESOLVED WORKSFORME

(Toolkit :: Video/Audio Controls, defect)

Description

[Hani Yacoub, Desktop QA]

[Affected versions]: 
Nightly 53.0a1

[Affected platforms]:
All platforms: Windows 10 x 64, Ubuntu 16.04, Mac OS X 10.12

[Steps to reproduce]:
1. Launch Nightly 53.0a1 with a new profile and then open this link https://people-mozilla.org/~ralin/vtt/.
2. Move the video till the end.
3. Move the video to the center of timeline.
4. Move the video till the end again.
5. Click play.

[Expected result]:
The video should play.

[Actual result]:
The video won't play after clicking once on the play button.
You have to click twice for the video to play.

Comment 1

[Ray Lin[:ralin]]

By watching the log, it looks like the video.currentTime has been set to as same as video.duration after dragged to the end of scrubber, and supposedly video should trigger 'end' event to let video control know the video is end. The behavior is just equal to old implementation, so I'm wondering where could go wrong. Perhaps, there's still some buffered frames haven't been played yet...

I'll look into this issue, keep NI flag.

Comment 2

[Ray Lin[:ralin]]

It's an interesting case(the length of video is 30.093061, but the scrubber only accurate to the third number of digits after decimal point ). I can reproduce this issue on Windows 10 with Firefox 47 as well. It seems that video control has never worked for this case, and I could not find a last good build. So, this issue might not be regressed by any, I think.

Hani, could you verify that this issue affects only 53? or all versions? Thank you.

Comment 3

[Ray Lin[:ralin]]

More information about debugging:

When move the scrubber till the end:
scrubber.value    is 30.093
scrubber.duration is 30.093061 
Still 0.000061 sec haven't been played yet...

Comment 4

[Hani Yacoub, Desktop QA]

it's actually affects all versions.

Comment 5

[Ray Lin[:ralin]]

Thank you Hani! This problem is fixable but perhaps should be put off after other higher priority bugs.
I have no idea how many cases(or ratio) of videos would be affected by this problem or is there's any other video length with more digits after decimal point (i.e. 30.093061042 is technically possible). 

-----
Correction to comment 3:
s/scrubber.duration/video.duration/

Comment 6

[Ray Lin[:ralin]]

(In reply to Hani Yacoub from comment #4)
> it's actually affects all versions.

Thanks. Based on it, this bug isn't a regression of bug 1271765.

Comment 7

[Julien Cristau [:jcristau]]

Too late for firefox 52, mass-wontfix.

Comment 8

[Giorgia Nichita, Release Desktop QA]

Closing this as WFM as the link provided is no longer available. Please reopen if necessary.