Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -g -O2 -fdebug-prefix-map=/build/bash-a6qmCk/bash-5.0=.
-fstack-protector-strong -Wformat -Werror=format-security -Wall
-Wno-parentheses -Wno-format-security
uname output: Linux n16-118-182 5.4.0-100-generic #113-Ubuntu SMP Thu Feb 3
18:43:29 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-pc-linux-gnu
Bash Version: 5.0
Patch Level: 17
Release Status: release
Description:
I was develop a bash-completion function which can auto-complete
history command. But when I use
$ compgen -W "$(fc -l -10)" -- "${COMP_WORDS[1]}"
It gave me a weird result.
After many debug, I found that compgen will do command subtitution
and parameter expansion in word list.
It executed every $(...) in bash history so it gave a weird result.
For example, this command
$ compgen -W '`ls`'
will display current dir's content.
$ compgen -W '$HOME'
will display the HOME dir instead of literal '$HOME'
$ compgen -W 'HOME' -- 'H'
will get HOME but
$ compgen -W '$HOME' -- '$'
will get nothing.
Repeat-By:
compgen -W "$(fc -l -10)" -- "${COMP_WORDS[1]}"
compgen -W '`ls`'
compgen -W '$HOME'
compgen -W '$HOME' -- '$'
