Custom path completion in Bash

Question

I want to write a bash_completion script for my own file system. I have client program which sends queries to some DB.

example:

my_prog --ls db_name:/foo/bar/

this command writes to stdout list of files in db_name:/foo/bar folder.

I want to enable autocompletion for this. So when i press tab it shows list of options.

my_prog --ls db_name:/foo/bar/<tab>

but in this case when I press tab and there is single option it replaces the current entered path, so I'm getting this:

$ my_prog --ls db_name:/foo/bar/<tab>
$ my_prog --ls file

But I want the match to be added to end of entered path.

Here is my completion function:

__complete_path()
{
    COMPREPLY=()

    if [[ ${1} == "" ]]
    then
        COMPREPLY=( "/" )
        compopt -o nospace
        return
    fi

    base=${1##*/}
    dir=${1%/*}

    options="my_prog --ls ${db}:${dir}"
    COMPREPLY=( $(compgen -W "${options}" -- ${base} ) )

    compopt -o nospace
}

Answer 1

I found this thread while trying something similar. This stackexchange post helped me in putting the autocomplete function below together. It isn't quite as the "normal" autocompletion as the full paths are shown, but otherwise you may find it useful.

_complete_func()
    local cur prev opts
    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"

    if [ $COMP_CWORD -eq 1 ]; then
    opts="some options for the program"
        COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
    elif [ $COMP_CWORD -ge 2 ]; then
    local files=("${cur}"*)
        COMPREPLY=( "${files[@]}")
fi
}
complete -o nospace -F complete_func command_to_autocomplete