No space after option with bash completion

Question

I'm trying to filter bash-completion suggestions. Here awf-gtk2 -s abc.png [TAB] display -h --help -s --screenshot (it's ridiculous) / and awf-gtk2 -s[TAB] add a space after -s (perfect), with:

_awf_gtk2_complete() {
    local cur prev
    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"
    local opts="-h --help -s --screenshot"
    case "$prev" in
        -h|--help|-v|--version|-l|--list-themes)
            return 1 # stop
            ;;
        -s|--screenshot)
            COMPREPLY=( $(compgen -d -- "$cur") )
            return 0
            ;;
    esac
    COMPREPLY=( $(compgen -W "$opts" -- "$cur") )
}
complete -F _awf_gtk2_complete awf-gtk2

With ChatGPT (sorry), we did that:

# made in chatGPT
_awf_gtk3_complete() {
    local cur prev
    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"

    local all_opts=(-h --help -v --version -l --list-themes -t --theme -s --screenshot --ltr --rtl)
    local single_opts=(-h --help -v --version -l --list-themes)

    declare -A opt_aliases=(
        [-h]=--help
        [--help]=-h
        [-v]=--version
        [--version]=-v
        [-l]=--list-themes
        [--list-themes]=-l
        [-t]=--theme
        [--theme]=-t
        [-s]=--screenshot
        [--screenshot]=-s
    )

    case "$prev" in
        -h|--help|-v|--version|-l|--list-themes)
            return 1 # stop
            ;;
        -s|--screenshot)
            COMPREPLY=( $(compgen -d -- "$cur") )
            return 0
            ;;
    esac

    local used=()
    local word
    for word in "${COMP_WORDS[@]:1}"; do
        if [[ "$word" == -* ]]; then
            used+=("$word")
            [[ -n "${opt_aliases[$word]}" ]] && used+=("${opt_aliases[$word]}")
        fi
    done

    local hide_single_use=false
    for word in "${used[@]}"; do
        case "$word" in
            -t|--theme|-s|--screenshot|--ltr|--rtl)
                hide_single_use=true
                break
                ;;
        esac
    done

    local remaining_opts=()
    local opt
    for opt in "${all_opts[@]}"; do
        local skip=false
        for u in "${used[@]}"; do
            [[ "$opt" == "$u" ]] && skip=true && break
        done
        if $hide_single_use; then
            for su in "${single_opts[@]}"; do
                [[ "$opt" == "$su" ]] && skip=true && break
            done
        fi
        $skip || remaining_opts+=("$opt")
    done

    local opts=${remaining_opts[*]}
    COMPREPLY=( $(compgen -W "$opts" -- "$cur") )
}
complete -F _awf_gtk3_complete awf-gtk3

The idea:

• if you are using -h --help -v --version -l --list-themes, completion suggests nothing else (it's ok)
• if you are using -t --theme, completion suggests themes names by running the program (it's ok)
• if you are using a short option, completion doesn't suggests the corresponding long option (it's ok)
• if you are using one option, completion doesn't suggests again the same option (it's ok)
• if you are using --ltr, completion doesn't suggests --rtl (but not yet, and it's not the problem)

The problem is: awf-gtk3 -t[TAB] or awf-gtk3 --theme[TAB] does NOT add a space! (awf-gtk3 --th[TAB] add a space and it's perfect). Why?

Answer 1

So, the problem is:

    local used=()
    local word
    for word in "${COMP_WORDS[@]:1}"; do
        ...
    done

The solution is:

    local used=()
    for ((i = 1; i < COMP_CWORD; i++)); do
        local word="${COMP_WORDS[$i]}"
        ...
    done

I'm not sure to understand why.