1425384 - pointerEvent button state returns incorrect value using Wacom stylus eraser

Status: NEW

(Core :: DOM: Events, defect, P3)

Description

[evitolins]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.108 Safari/537.36

Steps to reproduce:

1) Enable about:config dom.w3c_pointer_events.enabled
2) Test Wacom input on this debugging page: https://evitolins.github.io/pointer-events-debugger/



Actual results:

3) Observe during a "pointerdown" event, the button value will display a value of 0  (yes it's a bit difficult, unless you keep the stylus very still)


Expected results:

The value should instead be 5 

*https://developer.mozilla.org/en-US/docs/Web/API/Pointer_events

Comment 1

[evitolins]

For step #2, use the link below instead to isolate the specific event "pointerdown"

https://evitolins.github.io/pointer-events-debugger/#pointerdown


Also, Chrome 63.0... is working as expected on Mac, if you'd like to use for comparison.

Comment 2

[Ming-Chou Shih [:stone]]

Attachment: Define the button/buttons values of 4th/5th button and revise nsContentUtils::GetButtonsFlagForButton

We had used button value 4/5 for 4-th/5-th (back/forward) button in nsContentUtils::GetButtonsFlagForButton. This isn't matched to the Pointer Event spec. It seems okay to redefine the values of 4-th, 5-th and eraser button since we don't dispatch related events to content on Windows [1] and Linux [2]. On Mac, we only dispatch mouse events with left/right button [3].

[1] https://searchfox.org/mozilla-central/rev/48cbb200aa027a0a379b6004b6196a167344b865/dom/base/nsContentUtils.cpp#8455
[2] https://searchfox.org/mozilla-central/rev/48cbb200aa027a0a379b6004b6196a167344b865/widget/windows/nsWindow.cpp#5843
[3] https://searchfox.org/mozilla-central/rev/48cbb200aa027a0a379b6004b6196a167344b865/widget/gtk/nsWindow.cpp#2755
[4] https://searchfox.org/mozilla-central/rev/48cbb200aa027a0a379b6004b6196a167344b865/widget/cocoa/nsChildView.mm#4559

Comment 3

[Ming-Chou Shih [:stone]]

Attachment: (WIP) Part1: Define the button/buttons values of 4th/5th button and revise nsContentUtils::GetButtonsFlagForButton

Comment 4

[Ming-Chou Shih [:stone]]

Attachment: (WIP) Part2: pointerEvent button state returns incorrect value using Wacom stylus eraser

Comment 5

[goran.s.brkic]

I see that this bug is still unconfirmed, but there have been some work on it.
From my side I'm able to reproduce it on version 61.0.1

Just one sidenote: it impacts both button and buttons values

Hint: it is easier to see to reproduce it on https://patrickhlauke.github.io/touch/tracker/multi-touch-tracker-pointer-hud.html