shell-integration: bash: PROMPT_COMMAND: line 0: syntax error near unexpected token ;;' when PROMPT_COMMAND already ends in ;

[jmcgover]

Issue Description

Before every bash command after Ghostty commit 5425569, bash reports the following error:

bash: PROMPT_COMMAND: line 0: syntax error near unexpected token `;;'
bash: PROMPT_COMMAND: line 0: `_opam_env_hook;; __ghostty_hook'

Notes:

• It looks like 5425569 introduced this particular appending to PROMPT_COMMAND
• GNU bash, version 5.3.9(1)-release (aarch64-apple-darwin24.6.0)
• opam is the OCaml package manager
• I fixed the issue by not including the ; when appending to PROMPT_COMMAND if it already ends in ;:

The diff command (for posterity):

diff -u \
  <(curl https://raw.githubusercontent.com/ghostty-org/ghostty/2d347cad336b6d4bd461f33fe87d90e6aa269843/src/shell-integration/bash/ghostty.bash) \
  ${GHOSTTY_RESOURCES_DIR}/shell-integration/bash/ghostty.bash | delta

Expected Behavior

No PROMPT_COMMAND errors before any commands.

Actual Behavior

bash reports the following error before every command:

bash: PROMPT_COMMAND: line 0: syntax error near unexpected token `;;'
bash: PROMPT_COMMAND: line 0: `_opam_env_hook;; __ghostty_hook'

Reproduction Steps

1. On macOS, update to latest Ghostty: brew install --cask ghostty@tip
2. Use bash as the default terminal
3. Open a new Ghostty window
4. Observe error:

bash: PROMPT_COMMAND: line 0: syntax error near unexpected token `;;'
bash: PROMPT_COMMAND: line 0: `_opam_env_hook;; __ghostty_hook'

Ghostty Logs

Filtering the log data using "subsystem == "com.mitchellh.ghostty""
Timestamp                       Thread     Type        Activity             PID    TTL  
2026-03-08 15:53:12.149035-0700 0xa30e21   Info        0x1422e1e            19895  0    ghostty: [com.mitchellh.ghostty:ghostty] known but unimplemented action action=40
2026-03-08 15:53:12.154904-0700 0xa30e21   Info        0x1422e1e            19895  0    ghostty: [com.mitchellh.ghostty:io_exec] io_exec: found Ghostty resources dir: /Applications/Ghostty.app/Contents/Resources/ghostty
2026-03-08 15:53:12.155202-0700 0xa30e21   Info        0x1422e1e            19895  0    ghostty: [com.mitchellh.ghostty:io_exec] io_exec: shell integration automatically injected shell=.bash
2026-03-08 15:53:12.155461-0700 0xa30e21   Info        0x1422e1e            19895  0    ghostty: [com.mitchellh.ghostty:ghostty] known but unimplemented action action=22
2026-03-08 15:53:12.162913-0700 0xa3db18   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:io_exec] io_exec: started subcommand path=/usr/bin/login pid=24265
2026-03-08 15:53:45.041284-0700 0xa38d0e   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1
2026-03-08 15:53:45.041422-0700 0xa34a9f   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1
2026-03-08 15:53:45.041733-0700 0xa3b384   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1
2026-03-08 15:53:45.042327-0700 0xa3ce34   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1
2026-03-08 15:53:45.042442-0700 0xa3db17   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1
2026-03-08 15:53:45.042617-0700 0xa3d5e8   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1
2026-03-08 15:53:45.049916-0700 0xa38d0e   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1
2026-03-08 15:53:45.050239-0700 0xa34a9f   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1
2026-03-08 15:53:45.050447-0700 0xa3b384   Info        0x0                  19895  0    ghostty: [com.mitchellh.ghostty:generic_renderer] generic_renderer: updating display link display id=1

Ghostty Version

Ghostty 1.3.0-main+861a9cf53

Version
  - version: 1.3.0-main+861a9cf53
  - channel: tip
Build Config
  - Zig version   : 0.15.2
  - build mode    : .ReleaseFast
  - app runtime   : .none
  - font engine   : .coretext
  - renderer      : renderer.generic.Renderer(renderer.Metal)
  - libxev        : kqueue

OS Version Information

macOS Sequoia 15.7.4 (24G517) arm64

(Linux only) Display Server

None

(Linux only) Desktop Environment/Window Manager

No response

Minimal Ghostty Configuration

shell-integration = bash

Additional Relevant Configuration

bash

$ bash --version
GNU bash, version 5.3.9(1)-release (aarch64-apple-darwin24.6.0)
Copyright (C) 2025 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

opam: OCaml Package Manager

$ opam --version
2.5.0

I acknowledge that:

• I have reviewed the FAQ and confirm that my issue is NOT among them.
• I have searched the Ghostty repository (both open and closed Discussions and Issues) and confirm this is not a duplicate of an existing issue or discussion.
• I have checked the "Preview" tab on all text fields to ensure that everything looks right, and have wrapped all configuration and code in code blocks with a group of three backticks (```) on separate lines.

[mitchellh]

cc @jparise

[jparise]

Tracking as #11259

[jparise]

Fixed by #11260

[thosil]

Hello there,
I think the fix introduced a new bug.
For the record I'm using powerline on linux with bash, this is the error message I get on every line:

bash: PROMPT_COMMAND: line 2: syntax error near unexpected token `;'
bash: PROMPT_COMMAND: line 2: `; __ghostty_hook'

I put some debug things in ghostty.bash to understand (starting line 295):

  # Append our hook to PROMPT_COMMAND, preserving its existing type.
  # shellcheck disable=SC2128,SC2178,SC2179
  set -x
  if [[ ";${PROMPT_COMMAND[*]:-};" != *";__ghostty_hook;"* ]]; then
    if [[ -z "${PROMPT_COMMAND[*]}" ]]; then
      if (( BASH_VERSINFO[0] > 5 || (BASH_VERSINFO[0] == 5 && BASH_VERSINFO[1] >= 1) )); then
        PROMPT_COMMAND=(__ghostty_hook)
      else
        PROMPT_COMMAND="__ghostty_hook"
      fi
    elif [[ $(builtin declare -p PROMPT_COMMAND 2>/dev/null) == "declare -a "* ]]; then
      PROMPT_COMMAND+=(__ghostty_hook)
    else
      [[ "${PROMPT_COMMAND}" =~ \;[[:space:]]*$ ]] || PROMPT_COMMAND+=";"
      PROMPT_COMMAND+=" __ghostty_hook"
    fi
  fi
  echo "DEBUG: PROMPT_COMMAND:'$PROMPT_COMMAND'"
  set +x

And this is the output so you can see that PROMPT_COMMAND is somewhat buggy:

+ [[ ;_powerline_status_wrapper _powerline_set_prompt
; != *\;\_\_\g\h\o\s\t\t\y\_\h\o\o\k\;* ]]
+ [[ -z _powerline_status_wrapper _powerline_set_prompt
 ]]
++ builtin declare -p PROMPT_COMMAND
+ [[ declare -- PROMPT_COMMAND=$'_powerline_status_wrapper _powerline_set_prompt\n' == \d\e\c\l\a\r\e\ \-\a\ * ]]
+ [[ _powerline_status_wrapper _powerline_set_prompt
 =~ ;[[:space:]]*$ ]]
+ PROMPT_COMMAND+=';'
+ PROMPT_COMMAND+=' __ghostty_hook'
+ echo 'DEBUG: PROMPT_COMMAND:'\''_powerline_status_wrapper _powerline_set_prompt
; __ghostty_hook'\'''
DEBUG: PROMPT_COMMAND:'_powerline_status_wrapper _powerline_set_prompt
; __ghostty_hook'
+ set +x
bash: PROMPT_COMMAND: line 1: syntax error near unexpected token `;'
bash: PROMPT_COMMAND: line 1: `; __ghostty_hook'

[jparise]

I hadn't considered the case where an existing PROMPT_COMMAND ends with an explicit newline (which is what powerline appears to be doing here). #11621 should fix that:

diff --git a/src/shell-integration/bash/ghostty.bash b/src/shell-integration/bash/ghostty.bash
index 4be662ddf..667d7c86b 100644
--- a/src/shell-integration/bash/ghostty.bash
+++ b/src/shell-integration/bash/ghostty.bash
@@ -303,7 +303,7 @@ if (( BASH_VERSINFO[0] > 4 || (BASH_VERSINFO[0] == 4 && BASH_VERSINFO[1] >= 4) )
     elif [[ $(builtin declare -p PROMPT_COMMAND 2>/dev/null) == "declare -a "* ]]; then
       PROMPT_COMMAND+=(__ghostty_hook)
     else
-      [[ "${PROMPT_COMMAND}" =~ \;[[:space:]]*$ ]] || PROMPT_COMMAND+=";"
+      [[ "${PROMPT_COMMAND}" =~ (\;[[:space:]]*|$'\n')$ ]] || PROMPT_COMMAND+=";"
       PROMPT_COMMAND+=" __ghostty_hook"
     fi
   fi

[thosil]

yes it does! :-)
thanks

[tiesmaster]

There looks like another scenario that breaks the intergration: starting a subshell (using kubie). Starting from 1.3.0, I now get this:

 󰀵 ties@warmachine  ~   22:42  32s 
❯ kubie ctx jarvis
bash: __ghostty_hook: command not found

 󰀵 ties@warmachine ↕️  2  ~  ⛵ jarvis (default)   22:42 
❯

When I check the subshell, I see that __ghostty_hook is not defined, while it remains defined in PROMPT_COMMAND:

$ type __ghostty_hook
bash: type: __ghostty_hook: not found

$ echo $PROMPT_COMMAND
_direnv_hook;history -a; __zoxide_hook;starship_precmd; __ghostty_hook

When I clear out my .bashrc, this doesn't happen, as PROMPT_COMMAND doesn't carry over __ghostty_hook. For some reason, my current dotfiles does that, though, I'm not sure where that happens.

warmachine:~ ties$ type __ghostty_hook
__ghostty_hook is a function
__ghostty_hook ()
{
...
}
warmachine:~ ties$ echo $PROMPT_COMMAND
__ghostty_hook
warmachine:~ ties$ bash
bash-3.2$ type __ghostty_hook
bash: type: __ghostty_hook: not found
bash-3.2$ echo $PROMPT_COMMAND

bash-3.2$

I've check the previous version, and I can confirm that the error didn't happen in 1.2.0. I can source the shell integration from ${GHOSTTY_RESOURCES_DIR}/shell-integration/bash/ghostty.bash, which I've done now as temporary workaround. Though, I'm not sure if that's the proper solution here.

[jparise]

I see what's happening in the subshell case and am working on an improvement.

[jparise]

#11690 should address this case.

kubie or something else in the environment might be slightly misbehaving here by exporting/inheriting PROMPT_COMMAND (that's not typical, and it's not something our shell integration does), but I think it's helpful for us to handle this in a more friendly way.