Beta 4: problems with dead keys and custom keyboard layout (Neo2)

[Snaptags]

I use a custom keyboard layout called Neo2 offering multiple layers using modifier keys, e.g. <CAPS-LOCK>+<k> results in )
Since installing beta4 of PSReadline, every time I press <CAPS-LOCK> a @ character is added to my input, So instead of
git commit -am "message"
I end up "typing"
git commit @-am @"message@"

Environment data

PS version: 5.1.17763.316 / same for 6.2
PSReadline version: 2.0.0-beta4
os: 10.0.17763.470 (WinBuild.160101.0800)
PS file version: 10.0.17763.470 (WinBuild.160101.0800)
vi or standard edit mode.

Steps to reproduce or exception report

Install the Neo2 driver: https://github.com/neo-layout/neo-layout/blob/master/windows/Neo2.0_setup.exe
And add the "German (Neo 2.0)" keyboard layout to your input settings, open powershell and hit <caps-lock>

[hexawyz]

I think this is not entirely specific to custom keyboard layouts, since this kind of problem can also be produced with the standard out-of-the-box fr-FR layout. (And likely any layout with similar features)

Specifically:
All FR layouts have some kind of dead keys such as ^/¨, é/2/~ or è/7/` (Normal/Caps/AltGr) on the standard AZERTY layout. When any dead key is depressed (Not specifically the ones related to Right Alt/Altr Gr.), the character @ gets outputed for the dead key press, in addition to the normal delayed behavior.

e.g. if I press Alt Gr + 7 then Spacebar, I expect ` to be output. Instead, I'll get @`

So I suspect this is more a problem with dead keys than a specific layout.

@SteveL-MSFT While this does fix #854, this is indeed a regression introduced in beta4 😥

[SteveL-MSFT]

cc @daxian-dbw

[fabiano]

The same is happening here when I type ~, ^, ", '. My OS language is English and the keyboard is configured as United States-International.

Downgraded to 2.0.0-beta3 and it's working now.

PS version: 6.1.2
PSReadline version: 2.0.0-beta4
os: 10.0.17763.580 (WinBuild.160101.0800)
PS file version: 6.1.2

[Snaptags]

I just fetched and built your changes, but they don't work for me, unfortunately :-(

If I change
s = isDeadKey ? key.Key.ToString() : "@";
to
s = isDeadKey ? key.Key.ToString() : "\0";
then my meta keys work as they are supposed to.

But deadKey handling is still strange. E.g.:
<`><a><space><a> is supposed to result in à a - and it does.
<a><`><space><a> is supposed to result in a`a but with PSReadline I get à`a

[daxian-dbw]

I verified the fix with US-international and the default French keyboard layouts, but not on Neo2.
Based on the code snippet you pasted above, it looks isDeadKey is false when it's supposed to be true, meaning the Win32 API ToUnicode at https://github.com/PowerShell/PSReadLine/blob/master/PSReadLine/Keys.cs#L150 doesn't return the expected results.

Do I have to install the German language before installing the Neo2 keyboard?

And add the "German (Neo 2.0)" keyboard layout to your input settings, open powershell and hit

Does the "German (Neo 2.0)" keyboard layout comes with Windows by default (available in the Language settings)?

[Snaptags]

Sorry, forget to mention that I can confirm the fix for French and US-international.

Unfortunately the Neo layout does not come with Windows, you'd have to install it first to add it to the Language settings. So this may not be worth the effort :-)

[daxian-dbw]

Based on the code snippet you pasted above, it looks isDeadKey is false when it's supposed to be true, meaning the Win32 API ToUnicode at https://github.com/PowerShell/PSReadLine/blob/master/PSReadLine/Keys.cs#L150 doesn't return the expected results.

Hmm, I'm guessing that the Win32 function ToUnicode doesn't work with the Neo driver well enough :(