x/exp/shiny: value of event/key.Event.Rune inconsistent across platforms while control key is pressed

[aarzilli]

Please answer these questions before submitting your issue. Thanks!

What version of Go are you using (go version)?

go version go1.7 linux/amd64
go version go1.7 windows/amd64

What did you do?

Open a shiny window, log key events received, press ctrl+C on the window.

What did you expect to see?

I expected the value of event/key.Event.Rune to be the same on linux and windows

What did you see instead?

On linux ctrl+C produces the rune 'c', on windows 0x3 is reported instead. This isn't limited to 'c' all ctrl+key combinations produce different results on windows and linux. I think that the value of Rune should either be the same across platforms or always set to -1 when ctrl is pressed.

[alexbrainman]

We could do something similar to https://git.merproject.org/mer-core/qtbase/blob/dfe853bff90444edf92a993e391df853780c9e8d/src/plugins/platforms/windows/qwindowskeymapper.cpp#L539 (I just googled), if we want to return 'c' on windows.

Leaving for to @crawshaw and @nigeltao to decide.

Alex

[aarzilli]

I have noticed that there are also other discrepancies: CodeReturnEnter gets '\r' on windows, '\n' on linux; CodeTab and CodeDeleteBackspace return '\t' and '\b' on windows but -1 on linux.

[nigeltao]

Let me think about it...

[nigeltao]

I think that all platforms should behave the same. Specifically:

Ctrl-A should have Rune == -1.

CodeReturnEnter has Rune == '\n', especially as you can't set Rune == "\r\n" (a string) on Darwin.

CodeTab should have Rune == '\t'.

CodeDeleteBackspace (and CodeEscape) should have Rune == -1. I wouldn't expect a text editor to want '\x08' or '\x1b' runes inserted into the text.

WDYT? I'm happy to do the Linux and Mac changes if there's consensus.

[alexbrainman]

WDYT?

I don't use this package myself, so I am fine with whatever you decide. We could always change our mind once we know more.

Alex

[aarzilli]

I'm ok with this, but:

Ctrl-A should have Rune == -1.

what happens if the user presses Ctrl+<Some key that doesn't exist on a US keyboard>?