bash: seeing extra leading character '[' in command output

[jparise]

Discussed in #3566

^{Originally posted by jharshman December 27, 2024}
After compiling from source and running I am seeing an extra character in the output of every command. Is anyone else experiencing this? Shell is Bash and no modifications to the PS1.

[josh@serenity ghostty]$ echo hi
[hi
[josh@serenity ghostty]$ pwd
[/home/josh/Projects/ghostty

info: ghostty version=1.0.1-dev+0000000
info: ghostty build optimize=ReleaseFast
info: runtime=apprt.Runtime.gtk
info: font_backend=font.main.Backend.fontconfig_freetype
info: dependency harfbuzz=8.4.0
info: dependency fontconfig=21402
info: renderer=renderer.OpenGL
info: libxev backend=main.Backend.io_uring
info(os): setlocale from env result=en_US.UTF-8
info(gtk): GTK version build=4.12.4 runtime=4.16.5
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[mitchellh]

@jparise Thanks for converting. I can't tell from the discussion but did you get a lead on what is causing this? More importantly: do you have an easy reproduction?

[jparise]

@jparise Thanks for converting. I can't tell from the discussion but did you get a lead on what is causing this? More importantly: do you have an easy reproduction?

Unfortunately, no to both. I tried a bunch of things myself (details in the discussion), but I haven't been able to reproduce or identify the root cause. Multiple people have seen it in various Linux environments though.

[jharshman]

@jparise I'm happy to assist in creating an environment in which this is reproducible. Let me know if you want an extra set of hands on this.

[jparise]

@jparise I'm happy to assist in creating an environment in which this is reproducible. Let me know if you want an extra set of hands on this.

Yes, that would be very helpful. Thanks for the offer!

[vhodges]

I have replicated the issue outside of Ghostty (eg in Gnome Terminal) on NixOS.

Setup:

mkdir -p temp/share/ghostty/shell-integration/bash/
cp $GHOSTTY_RESOURCES_DIR/shell-integration/bash/* temp/share/ghostty/shell-integration/bash/ #(or from src/shell-integration/bash)

# Then run the following (I put them into a test.sh file I could 'source' repeatably)

export GHOSTTY_BASH_INJECT=true
export GHOSTTY_RESOURCES_DIR=$HOME/temp/share/ghostty
builtin source $GHOSTTY_RESOURCES_DIR/shell-integration/bash/ghostty.bash

I tried putting traces before and after all of the printf calls as well as the PS* entries and the '[' still prints before all of them. I don't believe the issue to be related to the prompt.