sub_subcommands.bash

_my-app() {
    local i cur prev opts cmds
    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"
    cmd=""
    opts=""

    for i in ${COMP_WORDS[@]}
    do
        case "${i}" in
            "$1")
                cmd="my__app"
                ;;
            help)
                cmd+="__help"
                ;;
            some_cmd)
                cmd+="__some_cmd"
                ;;
            sub_cmd)
                cmd+="__sub_cmd"
                ;;
            test)
                cmd+="__test"
                ;;
            *)
                ;;
        esac
    done

    case "${cmd}" in
        my__app)
            opts="-h -V -C -c --help --version --conf --config <file> first second test some_cmd help"
            if [[ ${cur} == -* || ${COMP_CWORD} -eq 1 ]] ; then
                COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                return 0
            fi
            case "${prev}" in
                *)
                    COMPREPLY=()
                    ;;
            esac
            COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
            return 0
            ;;
        my__app__help)
            opts="<SUBCOMMAND>..."
            if [[ ${cur} == -* || ${COMP_CWORD} -eq 2 ]] ; then
                COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                return 0
            fi
            case "${prev}" in
                *)
                    COMPREPLY=()
                    ;;
            esac
            COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
            return 0
            ;;
        my__app__some_cmd)
            opts="-h -V --help --version sub_cmd help"
            if [[ ${cur} == -* || ${COMP_CWORD} -eq 2 ]] ; then
                COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                return 0
            fi
            case "${prev}" in
                *)
                    COMPREPLY=()
                    ;;
            esac
            COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
            return 0
            ;;
        my__app__some_cmd__help)
            opts="<SUBCOMMAND>..."
            if [[ ${cur} == -* || ${COMP_CWORD} -eq 3 ]] ; then
                COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                return 0
            fi
            case "${prev}" in
                *)
                    COMPREPLY=()
                    ;;
            esac
            COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
            return 0
            ;;
        my__app__some_cmd__sub_cmd)
            opts="-h -V --config --help --version"
            if [[ ${cur} == -* || ${COMP_CWORD} -eq 3 ]] ; then
                COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                return 0
            fi
            case "${prev}" in
                --config)
                    COMPREPLY=($(compgen -W "Lest quotes aren't escaped." -- "${cur}"))
                    return 0
                    ;;
                *)
                    COMPREPLY=()
                    ;;
            esac
            COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
            return 0
            ;;
        my__app__test)
            opts="-h -V --case --help --version"
            if [[ ${cur} == -* || ${COMP_CWORD} -eq 2 ]] ; then
                COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                return 0
            fi
            case "${prev}" in
                --case)
                    COMPREPLY=($(compgen -f "${cur}"))
                    return 0
                    ;;
                *)
                    COMPREPLY=()
                    ;;
            esac
            COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
            return 0
            ;;
    esac
}

complete -F _my-app -o bashdefault -o default my-app