#!/bin/bash
#
# git-amend-commit - edit a commit message (like "git commit --amend", but
#                    works for non-HEAD patches).
#
# Copyright (C) 2008 Karel Zak <kzak@redhat.com>
#
# This file is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This file is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

CID="$1"

if [ -z "$CID" ]; then
	echo "Usage: $0 <commit>"
	exit 1
fi

MYBRANCH=$(git branch | gawk '/^\* / { print $2 }')
TMPBRANCH="tmp.$$"

git checkout -f -b "$TMPBRANCH" "$CID"
git commit --amend
git rebase --onto "$TMPBRANCH" "$CID" "$MYBRANCH"
git branch -d "$TMPBRANCH"

echo "done."