Git Bash on MinTTY can't handle `İ` on Turkish Q layout

[ahmetsait]

Existing issues matching what you're seeing

• I was not able to find an open or closed issue matching what I'm seeing

Git for Windows version

git version 2.51.0.windows.1
cpu: x86_64
built from commit: 4d21a77b98af5cf479d8b6f863c2aa94257cd4e1
sizeof-long: 4
sizeof-size_t: 8
shell-path: D:/git-sdk-64-build-installers/usr/bin/sh
feature: fsmonitor--daemon
libcurl: 8.15.0
OpenSSL: OpenSSL 3.2.4 11 Feb 2025
zlib: 1.3.1
SHA-1: SHA1_DC
SHA-256: SHA256_BLK
default-ref-format: files
default-hash: sha1

Windows version

Windows 10

Windows CPU architecture

x86_64 (64-bit)

Additional Windows version information

Microsoft Windows [Version 10.0.19045.6216]

Options set during installation

Editor Option: Notepad++
Custom Editor Path:
Default Branch Option:
Path Option: Cmd
SSH Option: OpenSSH
Tortoise Option: false
CURL Option: OpenSSL
CRLF Option: CRLFAlways
Bash Terminal Option: MinTTY
Git Pull Behavior Option: Merge
Use Credential Manager: Enabled
Performance Tweaks FSCache: Enabled
Enable Symlinks: Enabled
Enable FSMonitor: Disabled

Other interesting things

Turkish Q Keyboard Layout
mintty '3.7.9' ada33f38 (Msys-x86_64)

Terminal/shell

MinTTY Bash

Commands that trigger the issue

bash

Expected behaviour

AhmetSait@COMPUTER MINGW64 ~
$ sleep 5
aiaiai
AhmetSait@COMPUTER MINGW64 ~
$ aiaiai
bash: aiaiai: command not found

AhmetSait@COMPUTER MINGW64 ~
$ sleep 5
AİAİAİ
AhmetSait@COMPUTER MINGW64 ~
$ AİAİAİ
bash: AİAİAİ: command not found

Actual behaviour

Bash seem to screw up İ keys on Turkish Q layout while the standard input is busy:

AhmetSait@COMPUTER MINGW64 ~
$ sleep 5
aiaiai
AhmetSait@COMPUTER MINGW64 ~
$ aaa
bash: aaa: command not found

AhmetSait@COMPUTER MINGW64 ~
$ sleep 5
AİAİAİ
AhmetSait@COMPUTER MINGW64 ~
$ A▒A▒A▒
bash: $'A\260A\260A\260': command not found

AhmetSait@COMPUTER MINGW64 ~
$ bash --noediting

AhmetSait@COMPUTER MINGW64 ~
$ sleep 5
aiaiai
AhmetSait@COMPUTER MINGW64 ~
$
bash: $'a\Eia\Eia\Ei': command not found

AhmetSait@COMPUTER MINGW64 ~
$ sleep 5
AİAİAİ
AhmetSait@COMPUTER MINGW64 ~
$
bash: $'A\EİA\EİA\Eİ': command not found

Other characters are perfectly fine:

AhmetSait@COMPUTER MINGW64 ~
$ sleep 5
ğĞüÜşŞöÖçÇ
AhmetSait@COMPUTER MINGW64 ~
$ ğĞüÜşŞöÖçÇ
bash: ğĞüÜşŞöÖçÇ: command not found

This usually happens when I run a slow git operation and try to write the next git command before the previous command is finished:

AhmetSait@COMPUTER MINGW64 ~/Projects/Scintilla.NET (master)
$ git status
On branch master
Your branch is up to date with 'origin/master'.

nothing to commit, working tree clean

AhmetSait@COMPUTER MINGW64 ~/Projects/Scintilla.NET (master)
$ gt log
bash: gt: command not found

I can consistently reproduce this by switching to Turkish Q layout in Windows settings. US layout does not exhibit any similar issues.

Scan-code for Turkish İ key is 41 which corresponds to ' (Apostrophe) key in US layout:

Repository

No response

[ahmetsait]

Reported here since MinTTY maintainer thinks this is unrelated to MinTTY.
mintty/mintty#1333

[dscho]

Hmm. Maybe this has something to do with /etc/inputrc? Could you temporarily (as admin) rename that file and try again?

[ahmetsait]

Renaming /etc/inputrc made no difference.

[dscho]

Renaming /etc/inputrc made no difference.

Okay. Next attempt: Is it specific to Git for Windows, or does regular MSYS2 (on which Git for Windows is based) expose the same bug?

[ahmetsait]

I installed MSYS2 and it seems to work correctly:

[dscho]

Next attempt at figuring this out: Can you (temporarily, as admin) replace the usr/bin/msys-2.0.dll of the Git for Windows installation with the one from MSYS2 and try again?

[ahmetsait]

Done, but no difference.

[dscho]

Huh. This is strange. Maybe you can experiment with a PortableGit, deleting as many files from it as possible without breaking this example (a good first step would be to delete /mingw64, for example, you could probably start the git-bash.exe and simply do an rm -rf /usr/bin/* which would naturally skip (with errors) the files that are in use; The trickiest thing will be /etc/, I am sure).

[ahmetsait]

Deleting /usr/bin/cygwin-console-helper.exe fixes the bug (at the cost of opening a dummy ConHost window)

[dscho]

I strongly suspect that deleting that helper will let the MSYS2 runtime slip into a completely different console mode, and therefore I am wary that this might fail to lead us to the actual culprit...

[ahmetsait]

Okay. Renaming /mingw64/share/git/completion/git-prompt.sh also fixes the problem.

[dscho]

Aha! This probably means that the problem does lie in the MSYS2 runtime, it's just that it does not necessarily surface with regular MSYS2 because its PS1 does not call a native Win32 executable (such as git.exe). I bet that is the problem.

[ahmetsait]

I confirm that changing PS1 can turn the bug on/off at runtime (without requiring restart).
Do I have to report this to msys2-runtime or would you like to track this yourself?

[dscho]

Let's try to come up with a PS1 that reproduces the error without Git for Windows. Maybe a PowerShell invocation calling Start-Sleep -Seconds 5 would do the job?

Once we have that in hand, we can see whether it even reproduces in Cygwin (which I strongly suspect to be the case).

[dscho]

@ahmetsait did you make some progress coming up with such a PS1?