Can bash autocomplete be used with source?-CodePudding

I have a project where I'm regularly switching out different versions of a library. I have a script set_lib that takes the library version as input and then sets the relevant environment variables. Sometimes I want to source this script and build/run things manually. I know how to configure autocomplete for functions/scripts, but what about for sourcing scripts? That is

>source set_lib v<tab><tab>
ver1 ver2 ver3

Also, I would like to keep autocomplete working as normal with source when not in conjunction with set_lib.

EDIT: As suggested I tried the following

_comp_set_lib() {
    if [ ${COMP_WORDS[1]} == 'set_lib' ]; then
        COMPREPLY=( "set_lib ver1" "set_lib ver2" )
    fi
}
complete -o bashdefault -F _comp_set_lib source

$COMP_CWORD being the second position is giving me problems. The above doesn't work as expected and gives me

>source set_lib <tab>
source set_lib ver

CodePudding user response：

I think the most convenient approach is to define a function that wraps source set_lib ...:

function set_lib() {
  source set_lib "$@"
}

and then set up autocompletes for that function.

But if you prefer to have to type source set_lib and not just set_lib, then you can attach an autocompletion function to the source builtin, and have it check whether "${COMP_WORDS[1]}" (meaning the first argument to source) equals set_lib before deciding whether to return any custom matches. (When using the complete builtin to set up the autocomplete, use the -o bashdefault flag to tell it that if your function doesn't return any matches then you want Bash to fall back to its default logic for suggestions.)

CodePudding user response：

Usually you need to invoke compgen for custom completion spec. See the following example:

_comp_set_lib()
{
    local cur=$2
    local versions=(v1 ver2 version3)

    if [[ ${COMP_WORDS[1]} == set_lib ]]; then
        COMPREPLY=( $( compgen -W "${versions[*]}" -- "$cur" ) )
        return
    fi
}
complete -o default -o bashdefault -F _comp_set_lib source