systemd/shell-completion/bash/systemd-cgtop

# systemd-cgtop(1) completion                  -*- shell-script -*-
# SPDX-License-Identifier: LGPL-2.1+
#
# This file is part of systemd.
#
#
# 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
}

__get_machines() {
        local a b
        machinectl list --no-legend --no-pager | { while read a b; do echo " $a"; done; };
}

_systemd_cgtop() {
        local cur=${COMP_WORDS[COMP_CWORD]} prev=${COMP_WORDS[COMP_CWORD-1]}
        local comps

        local -A OPTS=(
               [STANDALONE]='-h --help --version -p -t -c -m -i -b --batch -r --raw -k -P'
               [ARG]='--cpu --depth -M --machine --recursive -n --iterations -d --delay --order'
               )

        _init_completion || return

        if __contains_word "$prev" ${OPTS[ARG]}; then
                case $prev in
                        --machine|-M)
                                comps=$( __get_machines )
                        ;;
                        --recursive)
                                comps='yes no'
                        ;;
                        --order)
                                comps='path tasks cpu memory io'
                        ;;
                esac
                COMPREPLY=( $(compgen -W '$comps' -- "$cur") )
                return 0
        fi

        COMPREPLY=( $(compgen -W '${OPTS[*]}' -- "$cur") )
}

complete -F _systemd_cgtop systemd-cgtop