1160418 - B2G: MouseEvent.buttons returns 0 for taps while Fennec returns 1

Status: RESOLVED INVALID

(Core :: DOM: Events, defect)

Description

[Kohei Yoshino [:kohei]]

I have recently noticed that my BzDeck app doesn't respond to tap gestures on B2G Nightly. My debugging finds that event.buttons now returns 0 instead of 1. Maybe 0 is correct in theory because it's not triggered by the mouse left button, but this property should return 1 for site compatibility. Firefox for Android still returns 1 for taps.

https://github.com/bzdeck/bzdeck/issues/269
https://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/buttons

Comment 1

[u279076]

Is this reproducing on a particular device or the emulator?

Comment 2

[Kohei Yoshino [:kohei]]

Attachment: testcase

I'm on a Flame phone. I have already worked around the issue in the BzDeck code so it can no longer be reproduced on the app. Here's a pretty simple testcase to see the MouseEvent.buttons value.

Comment 3

[Kohei Yoshino [:kohei]]

Here's my results:

* Mac: 1
* Android: 1
* Firefox OS: 0

Comment 4

[Kohei Yoshino [:kohei]]

Attachment: testcase

Check both MouseEvent.button and MouseEvent.buttons...

Comment 5

[u279076]

Thanks, the testcase works for me.

Desktop Firefox 40.0a1 returns 1 on click.
B2G 2.2.0.0-pre on my Nexus 4 returns 0 on tap.

I don't have my Flame handy and am away from the office for the next week. I can try to regress this when I get back. Kohei, it would save us some time if you want to take a crack at regressing this.

Comment 6

[Kohei Yoshino [:kohei]]

I'll check for the regression range. Not so long time ago.

Comment 7

[Kohei Yoshino [:kohei]]

Hmm. Looks like it's not a recent regression or maybe not a regression.

Actually the Firefox OS system and some apps on my Flame phone had not got updated for a month or so for some reason until I flashed them manually, so the possible scenario is BzDeck was also old and therefore it was working even after I change my code late March:

https://github.com/bzdeck/flaretail.js/commit/77b36a2562ee40ded9a6789a00787659bfe34a7f

But, anyway, the current B2G behaviour doesn't match Fennec. Or, B2G might be right and Fennec should also return 0 for taps, though I guess it's returning 1 for a compatibility reason.

Comment 8

[Anne (:annevk)]

Closing as B2G is obsolete.