systemd/shell-completion/bash/busctl

# hostnamectl(1) completion                               -*- shell-script -*-
#
# This file is part of systemd.
#
# Copyright 2013 Zbigniew Jędrzejewski-Szmek
#
# systemd is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# systemd is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with systemd; If not, see <http://www.gnu.org/licenses/>.

__contains_word () {
        local w word=$1; shift
        for w in "$@"; do
                [[ $w = "$word" ]] && return
        done
}

_busctl() {
        local i verb comps
        local cur=${COMP_WORDS[COMP_CWORD]} prev=${COMP_WORDS[COMP_CWORD-1]}
        local -A OPTS=(
               [STANDALONE]='-h --help --version --no-pager --system --user
                             --no-unique --no-machine'
                      [ARG]='-H --host -M --machine --address
                             --match'
        )

        if __contains_word "$prev" ${OPTS[ARG]}; then
                case $prev in
                        --host|-H)
                                comps=$(compgen -A hostname)
                        ;;
                esac
                COMPREPLY=( $(compgen -W '$comps' -- "$cur") )
                return 0
        fi

        if [[ "$cur" = -* ]]; then
                COMPREPLY=( $(compgen -W '${OPTS[*]}' -- "$cur") )
                return 0
        fi

        local -A VERBS=(
                [STANDALONE]='list monitor'
        )

        for ((i=0; i < COMP_CWORD; i++)); do
                if __contains_word "${COMP_WORDS[i]}" ${VERBS[*]} &&
                 ! __contains_word "${COMP_WORDS[i-1]}" ${OPTS[ARG]}; then
                        verb=${COMP_WORDS[i]}
                        break
                fi
        done

        if [[ -z $verb ]]; then
                comps=${VERBS[*]}
        elif __contains_word "$verb" ${VERBS[STANDALONE]}; then
                comps=''
        fi

        COMPREPLY=( $(compgen -W '$comps' -- "$cur") )
        return 0
}

complete -F _busctl busctl