git-rnotes

#!/bin/bash
#
# Wrapper around 'git notes' to make it easier to share notes to and
# from remote repositories.

safe_git () {
    echo "git $*"
    if ! git "$@"; then
        exit 1
    fi
}

fetch () {
    if ! git rev-parse "$local_notes" >/dev/null 2>&1; then
        # First-time fetch of remote notes
        safe_git fetch $remote $local_notes:$local_notes
    fi

    # This one serves like the remote tracking branch, except that we
    # have to handle the tracking ourselves.
    safe_git fetch $remote $local_notes:$remote_notes
}

push () {
    safe_git push $remote $local_notes:$local_notes
    fetch
}

# This should be only done manually by people who really know
# what they're doing.
#
# push_f () {
#     safe_git push -f $remote $local_notes:$local_notes
# }

merge () {
    safe_git notes merge -v $remote_notes
}

pull () {
    fetch && merge
}

me=`basename $0`

usage () {
    # Call as: usage [EXITCODE] [USAGE MESSAGE]
    exit_code=1
    if [[ "$1" == [0-9] ]]; then
        exit_code="$1"
        shift
    fi
    if [ -n "$1" ]; then
        echo >&2 "$*"
        echo
    fi

    cat <<EOF >&2
Usage: $me [options] SUBCOMMAND REMOTE
Options:
  -h, --help     Show this help and exit

Subcommands:

  fetch
  push
  merge
  pull

EOF
    exit "$exit_code"
}

parse_args () {
    if [ "$1" == '-h' ] || [ "$1" == '--help' ]; then
        usage 0
    fi

    [ $# = 2 ] || usage

    subcommand="$1" remote="$2"

    notes_namespace=$( git notes get-ref )
    if [[ $notes_namespace != refs/notes/* ]]; then
        echo >&2 "ERROR: Notes namespace '$notes_namespace' wasn't prefixed with 'refs/notes/'; aborting"
        exit 1
    fi
    notes_namespace="${notes_namespace#refs/}"
    notes_namespace="${notes_namespace#notes/}"

    local_notes="refs/notes/$notes_namespace"
    remote_notes="refs/notes/$remote/$notes_namespace"
}

main () {
    parse_args "$@"
    
    case "$subcommand" in
        fetch|push|pull|merge)
            "$subcommand"
            ;;
        *)
            usage
            ;;
    esac
}

main "$@"