git-fossil.sh

#! /bin/sh
# :vim setf sh:
# 
# Copyright (c) 2013 Bryan Drewery <bryan@shatow.net>
# All rights reserved.
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.

set -e
set -x

usage() {
	cat << EOF
	git fossil <cmd> [args]

	rebase    -- Rebase current branch on the latest fossil version
	dcommit   -- Commit changes upstream

	-n:       Dry-mode, show what would be done
EOF
}

stash() {
	[ -z "$(git status --porcelain)" ] && return 0
	git stash
	STASHED=1
}

unstash() {
	if [ ${STASHED:-0} -eq 1 ]; then
		git stash pop
		STASHED=0
	fi
}

check_untracked_files() {
	if [ -n "$(git ls-files --other --exclude-standard)" ]; then
		echo "Error: UNTRACKED FILES!" >&2
		git ls-files --other --exclude-standard
		exit 1
	fi
}


exit_handler() {
	unstash
}

trap exit_handler EXIT

cmd_dcommit() {
	local current_branch merge_base hash

	check_untracked_files

	current_branch="$(git rev-parse --abbrev-ref HEAD)"
	merge_base=$(git merge-base ${current_branch} fossil)
	cmd_rebase

	set -e
	git rev-list --reverse ${merge_base}..HEAD | while read hash; do
		[ $DRY_MODE -eq 0 ] && git checkout ${hash}
		log=$(git log -1 --pretty="format:%B" ${hash})
		if [ $DRY_MODE -eq 1 ]; then
			echo "Would commit ${hash}: "
			echo "${log}" | sed -e 's,^,	,'
			git show --name-status -M -C --pretty="format:" ${hash}
		else
			git show --name-status -M -C --pretty="format:" \
			    ${hash} | while read status file newfile; do
				case ${status} in
					A)
						fossil add "${file}"
						;;
					C*)
						fossil cp "${file}" \
						    "${newfile}"
						;;
					D)
						fossil rm "${file}"
						;;
					R*)
						fossil mv "${file}" \
						    "${newfile}"
						#mv "${file}" "${newfile}"
						;;
					M)
						touch "${file}"
						;;
					*)
						;;
				esac
			done
			fossil status
			yes|fossil commit -m "${log}"
			update_fossil_branch force
			#merge_base=$(git merge-base HEAD fossil)
			#git checkout ${current_branch}
			#git rebase --onto fossil ${merge_base}
		fi
	done

	git checkout ${current_branch}
	git reset --hard fossil
}

update_fossil_branch() {
	local current_branch fossil_hash force=0

	[ $# -eq 1 ] && force=1

	current_branch="$(git rev-parse --abbrev-ref HEAD)"

	git checkout -f fossil

	fossil update
	fossil revert >/dev/null 2>&1
	#if [ $force -eq 1 ] || [ -n "$(fossil diff --brief)" ]; then
	if [ $force -eq 1 ] || [ -n "$(git status --porcelain)" ]; then
		fossil_hash="$(fossil status |
		    awk '$1 == "checkout:" {print $2}')"
		fossil_url="$(fossil remote-url)"
		fossil clean -f
		git add -A .
		### XXX: Need actual commit message in here from fossil
		### XXX: Need to use git-notes for this crap.
		git commit -a --author="Git Fossil <git-fossil@shatow.net>" \
		    -m "Sync with fossil"
		git notes add -m "${fossil_url}@${fossil_hash}" HEAD
	fi

	git checkout -f ${current_branch}
}


cmd_rebase() {
	local current_branch merge_base fossil_url

	check_untracked_files
	stash

	update_fossil_branch

	merge_base=$(git merge-base HEAD fossil)
	git rebase --onto fossil ${merge_base}
}

DRY_MODE=0
cmd="$1"
shift

while getopts "n" FLAG; do
	case "${FLAG}" in
		n)
			DRY_MODE=1
			;;
	esac
done
shift $((OPTIND-1))

case ${cmd} in
	dcommit)
		cmd_dcommit "$@"
		;;
	rebase)
		cmd_rebase "$@"
		;;
	*)
		usage
		;;
esac