.fab_bash_completion

#!/bin/bash

#
# Name:          fab_bash_completion
# Description:   Adds tab-completion to fabfile tasks
# Date:          2009-10-28
#
# Author:        Enrico Batista da Luz
# E-mail:        rico.bl@gmail.com
# Website:       http://ricobl.wordpress.com/
#
# Installation:  point to this file from your .bash_profile, like so:
#
#   ~/path/to/fab_bash_completion
#
# Mostly adapted from:
#
#   http://www.debian-administration.org/article/An_introduction_to_bash_completion_part_2
#   http://technotales.wordpress.com/2010/01/10/rake-and-capistrano-bash-completion/
#   http://www.unix.com/shell-programming-scripting/99282-silent-background-process.html
#

_fab_list () {
    # Get the list of available tasks,
    # ignoring errors (missing or invalid fabfile)
    fab --shortlist 2> /dev/null
}

_fab_completion() {
    local cur prev opts cache_file

    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"
    cache_file=".fab_completion"

    # Read from cache file or get a fresh list
    if [ -e "$cache_file" ]; then
        opts=`cat $cache_file`
    else
        opts=`_fab_list`
    fi

    COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )

    # Always update the local cache in background
    (_fab_list > $cache_file &) > /dev/null

    return 0
}

complete -F _fab_completion -o default fab