bash: __bp_last_argument_prev_command: parameter null or not set

[erhhung]

Checks

• I ran cw doctor in the affected command line session and it didn't resolve my issue
• I ran cw restart and it didn't resolve my issue
• I searched the discussions in this repo and there are no duplicates of my issue

Expected behaviour

There is some weird interaction between Code Whisperer and Bash completion for commands like "nats" (https://github.com/nats-io/natscli) (I've also seen the same error with a couple of other commands, but forgot which ones...)

If I disable CW (by commenting out both the pre block and post block in my ~/.bash_profile) while keeping nats shell completion (via source <(nats --completion-script-bash)), I experience no issues. But, if both are enabled, then the "bash: __bp_last_argument_prev_command: parameter null or not set" error always shows as the first line after pressing the return key in my Bash shell after tab completion has been triggered once, regardless if the current command can be completed.

The only reference I found online related to the variable __bp_last_argument_prev_command is fig, which is now CW.

Actual behaviour

See keypress-by-keypress descriptions below.

Steps to reproduce

Some examples:

# no problem
$ nats<return>
usage: nats [<flags>] <command> [<args> ...]
...

# no problem
$ nats<tab><space-inserted> <return>
usage: nats [<flags>] <command> [<args> ...]

# bug appears
$ nats<tab><space-inserted> <tab><no-changes><return>
bash: __bp_last_argument_prev_command: parameter null or not set
usage: nats [<flags>] <command> [<args> ...]
...

# bug appears
$ nats cont<tab><subcommand-completed>ext<space-inserted> <return>
bash: __bp_last_argument_prev_command: parameter null or not set
error: a subcommand from the list below is required, use --help for full help including flags and arguments
...error expected...

# bug appears
$ nats cont<tab><subcommand-completed>ext<space-inserted> ls<return>
bash: __bp_last_argument_prev_command: parameter null or not set
...table output...

Environment

CODEWHISPERER-details:
  - 0.13.0
hardware-info:
  - model: 
  - model-id: 
  - chip-id: Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
  - cores: 8
  - mem: 64.00 GB
os-info:
  - macOS 14.2.1 (23C71)
environment:
  - shell: /usr/local/Cellar/bash/5.2.21/bin/bash
  - terminal: iterm
  - cwd: /Users/erhhung
  - exe-path: /Users/erhhung/.local/bin/cw
  - install-method: unknown
  - env-vars:
    - SHELL: /usr/local/bin/bash
    - CWTERM_SESSION_ID: 0c1da728a5fe4a2bb2cbc501344b7b05
    - __CFBundleIdentifier: com.googlecode.iterm2
    - TERM: xterm-256color
    - DISPLAY: :0.0
    - CW_TERM: 0.13.0
    - CW_SET_PARENT_CHECK: 1
    - PATH: /Users/erhhung/.local/bin:/Users/erhhung/.krew/bin:/Users/erhhung/.go/bin:/Users/erhhung/.pyenv/shims:/usr/local/opt/tcl-tk/bin:/usr/local/opt/openjdk/libexec/openjdk.jdk/Contents/Home/bin:/Users/erhhung/.perl5/bin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/Users/erhhung/.local/bin:/opt/confluent/bin

[erhhung]

Figured out the issue I was having, which was caused by me messing around with the important $PROMPT_COMMAND environment variable inside my "~/.bash_profile" after the CodeWhisperer pre block:

# CodeWhisperer pre block. Keep at the top of this file.
[[ -f "${HOME}/Library/Application Support/codewhisperer/shell/bash_profile.pre.bash" ]] && builtin source "${HOME}/Library/Application Support/codewhisperer/shell/bash_profile.pre.bash"

_bash_history_sync() {
  builtin history -a
}

# DON'T JUST REPLACE PROMPT_COMMAND
PROMPT_COMMAND="_bash_history_sync"

Always append to existing $PROMPT_COMMAND:

if [[ "$PROMPT_COMMAND" != *_bash_history_sync* ]]; then
  PROMPT_COMMAND="_bash_history_sync; $PROMPT_COMMAND"
fi