1278268 - Update widget wheel synthesization functions to move the mouse cursor if needed

Status: RESOLVED FIXED

(Core :: Panning and Zooming, defect)

Description

[Kartikaya Gupta (email:[e-mail])]

(In reply to Botond Ballo [:botond] from bug 1276107 comment #39)
> (In reply to Kartikaya Gupta (email:[e-mail]) from bug 1276107 comment #37)
> > Another, perhaps better, option to avoid the footgun is to modify the
> > wheel-synthesization functions in the widget code to move the mouse to
> > provided coordinates before synthesizing the wheel. I'm not 100% sure if
> > that would work though.
> 
> Discussed this with Kats; this will be explored in a follow-up.

This bug is the follow-up.

Comment 1

[Kartikaya Gupta (email:[e-mail])]

Sadly after two days of tinkering with this I am still unable to get it to work on Windows. It looks like if you inject a mousemove followed by a mousewheel into the Windows APIs you still get the mousewheel message back before the mousemove. What a disaster.

Comment 2

[Kartikaya Gupta (email:[e-mail])]

I even tried throwing in some NS_DispatchToMainThread calls to spin the event loop and wasn't successful.

The next option is to provide a guarantee that any move-synth call will fire a mousemove event. That way even no-op moves will fire a mousemove event and we don't need to track the coordinates in JS to know if it's a no-op or not.

Comment 3

[Kartikaya Gupta (email:[e-mail])]

Turns out windows itself does send us the mousemove event, but in the widget code we run into the condition at [1] and drop it. I have patches that seem to be working on all platforms now. Try pushes coming shortly.

Comment 4

[Kartikaya Gupta (email:[e-mail])]

[1] http://searchfox.org/mozilla-central/rev/3f096f780166bc4772199d79a79c8e3541ff99be/widget/windows/nsWindow.cpp#4033

Comment 5

[Kartikaya Gupta (email:[e-mail])]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=ce19ae49d04f
https://treeherder.mozilla.org/#/jobs?repo=try&revision=dd4dc0f3de9c

Comment 6

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1278268 - Fix a latent bug in a test where we try to scroll something before it's layerized.

Review commit: https://reviewboard.mozilla.org/r/58672/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/58672/

Comment 7

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1278268 - Back out cset 8c896f70f97b from bug 1276107 as we have a better fix in hand.

Review commit: https://reviewboard.mozilla.org/r/58674/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/58674/

Comment 8

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1278268 - Ensure that no-op mousemove synthesizations on Windows still fire a mousemove event.

Review commit: https://reviewboard.mozilla.org/r/58676/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/58676/

Comment 9

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1278268 - Simplify some test code to use the moveMouseAndScrollWheelOver function.

Review commit: https://reviewboard.mozilla.org/r/58678/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/58678/

Comment 10

[Jim Mathies [:jimm]]

Comment on attachment 8761569 [details]
Bug 1278268 - Ensure that no-op mousemove synthesizations on Windows still fire a mousemove event.

https://reviewboard.mozilla.org/r/58676/#review55760

looks ok to me.

Comment 11

[Botond Ballo [:botond]]

Comment on attachment 8761567 [details]
Bug 1278268 - Fix a latent bug in a test where we try to scroll something before it's layerized.

https://reviewboard.mozilla.org/r/58672/#review55906

Comment 12

[Botond Ballo [:botond]]

Comment on attachment 8761568 [details]
Bug 1278268 - Back out cset 8c896f70f97b from bug 1276107 as we have a better fix in hand.

https://reviewboard.mozilla.org/r/58674/#review55912

Comment 13

[Botond Ballo [:botond]]

Comment on attachment 8761570 [details]
Bug 1278268 - Simplify some test code to use the moveMouseAndScrollWheelOver function.

https://reviewboard.mozilla.org/r/58678/#review55914

Comment 14

[Botond Ballo [:botond]]

Thanks for figuring out a proper solution to this footgun, and doing this cleanup!

Comment 15

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/38d10c62b33b
Fix a latent bug in a test where we try to scroll something before it's layerized. r=botond
https://hg.mozilla.org/integration/mozilla-inbound/rev/9d17d61ee826
Back out cset 8c896f70f97b from bug 1276107 as we have a better fix in hand. r=botond
https://hg.mozilla.org/integration/mozilla-inbound/rev/acc080f11d72
Ensure that no-op mousemove synthesizations on Windows still fire a mousemove event. r=jimm
https://hg.mozilla.org/integration/mozilla-inbound/rev/1f6385cec917
Simplify some test code to use the moveMouseAndScrollWheelOver function. r=botond

Comment 16

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/9d17d61ee826

Comment 17

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/38d10c62b33b
https://hg.mozilla.org/mozilla-central/rev/acc080f11d72
https://hg.mozilla.org/mozilla-central/rev/1f6385cec917

Comment 18

[Kartikaya Gupta (email:[e-mail])]

I don't think this needs uplifting.