bash completion for the `-a` and `-b` flags of the Mac OS X `open` command

open.sh

#
# This is a set of bash function definitions, and a bash command, that
# set up bash completion for the Mac OS X "open" command.
#
# HOW TO USE
#
# Add this command to your .bashrc:
#
# . open.sh
#
# (Adjust the filename to wherever you put this file.)
# 
# WHAT THIS ACTUALLY DOES
#
# When you try to complete a word after "open -a", bash will match the
# word against the names of the apps on your Mac.  Example:
#
# $ open -a Ado<TAB>
# AdobePatchInstaller                    Adobe\ Bridge\ CS6                     Adobe\ Media\ Player
# Adobe\ AIR\ Application\ Installer     Adobe\ Encore\ CS6                     Adobe\ Photoshop\ CS6
# Adobe\ AIR\ Uninstaller                Adobe\ Extension\ Manager\ CS6         Adobe\ Prelude\ CS6
# Adobe\ AIR\ Updater                    Adobe\ Fireworks\ CS6                  Adobe\ Premiere\ Pro\ CS6
# Adobe\ After\ Effects\ CS6             Adobe\ Flash\ CS6                      Adobe\ SpeedGrade\ CS6
# Adobe\ After\ Effects\ Render\ Engine  Adobe\ Help                            Adobe\ Story
# Adobe\ Application\ Manager            Adobe\ Illustrator                     
# Adobe\ Audition\ CS6                   Adobe\ Media\ Encoder\ CS6             
# $ open -a Adobe
#
# When you try to complete a word after "open -b", bash will match the
# word against the bundle identifiers of the apps on your Mac.  Example:
#
# :; open -b com.ado
# com.adobe.AdobePremierePro                                       com.adobe.air.Installer
# com.adobe.AdobeStory.4875E02D9FB21EE389F73B8D1702B320485DF8CE.1  com.adobe.air.NativeTemplate
# com.adobe.AfterEffects                                           com.adobe.air.Template
# com.adobe.Audition.5.0                                           com.adobe.ame.application
# com.adobe.Encore                                                 com.adobe.amp.4875E02D9FB21EE389F73B8D1702B320485DF8CE.1
# com.adobe.ExtensionManager                                       com.adobe.bridge5
# com.adobe.Installers.Redirector                                  com.adobe.csi.CS6ServiceManager
# com.adobe.Installers.Setup                                       com.adobe.director.projector
# com.adobe.PDApp                                                  com.adobe.dynamiclinkmanager
# com.adobe.PDApp.AAMRegistrationNotifier                          com.adobe.dynamiclinkmediaserver
# com.adobe.PDApp.AAMUpdatesNotifier                               com.adobe.estoolkit-3.8
# com.adobe.Photoshop                                              com.adobe.flash
# com.adobe.Prelude                                                com.adobe.headlights.LogTransport2App
# com.adobe.adobe_licutil                                          com.adobe.illustrator
# com.adobe.air.ApplicationInstaller                               com.adobe.switchboard-2.0
# :; open -b com.adobe.
#
# CACHING
#
# These functions use Spotlight to find your applications and their
# bundle identifiers.  Getting the list of applications is pretty fast
# (after it's done the first time).  Getting the bundle identifiers is
# a little slower.  To speed it up, you can set the shell variable
# CompleteOpenBundleCache to a path.  The first time I need bundle
# identifiers, I will cache them at that path.  On subsequent uses, I
# will use the cached identifiers.  I don't invalidate the cache
# automatically.  Just delete it when it gets out of date:
#
# rm -f "$CompleteOpenBundleCache"
#

_complete_open () {
    local priorWord="$3" word="$2"
    case "$priorWord" in
        -a) _complete_open_app "$word" ;;
        -b) _complete_open_bundle "$word" ;;
        *) COMPREPLY=() ;;
    esac
}

_complete_open_app () {
    local word="$1*" appPath appName
    declare -i i=0
    COMPREPLY=()
    while IFS= read -r -d $'\0' appPath; do
        appName="${appPath##*/}"
        appName="${appName%.app}"
        if [[ "$appName" == $word ]]; then
            COMPREPLY[i++]="$(_complete_open_helper_escape "$appName")"
        fi
    done < <(mdfind -0 'kMDItemContentType == "com.apple.application-bundle"')
}

_complete_open_bundle () {
    local word="$1*" bundle
    declare -i i=0
    COMPREPLY=()
    while IFS= read -r -d $'\0' bundle; do
        if [[ "$bundle" != '' && "$bundle" == $word ]]; then
            COMPREPLY[i++]="$(_complete_open_helper_escape "$bundle")"
        fi
    done < <(_complete_open_helper_bundles)
}

_complete_open_file () {
    local file
}

_complete_open_helper_bundles () {
    if [[ "$CompleteOpenBundleCache" == '' ]]; then
        _complete_open_helper_bundles_uncached
    else
        if [[ ! -f "$CompleteOpenBundleCache" ]]; then
            rm -f "$CompleteOpenBundleCache"
            _complete_open_helper_bundles_uncached > "$CompleteOpenBundleCache"
        fi
        cat "$CompleteOpenBundleCache"
    fi
}

_complete_open_helper_bundles_uncached () {
    mdfind -0 'kMDItemContentType == "com.apple.application-bundle"' \
    | xargs -0 mdls -raw -nullMarker '' -name kMDItemCFBundleIdentifier
}

_complete_open_helper_escape () {
    echo -n "$1" | sed 's/[^-A-Za-z0-9_.,:@%=+/]/\\&/g'
}

complete -o bashdefault -o default -F _complete_open open