Re: RFC: grafts generalised

["Dmitry Potapov" <dpotapov@gmail.com>]

On Wed, Jul 2, 2008 at 10:10 PM, Stephen R. van den Berg <srb@cuci.nl> wrote:
> Dmitry Potapov wrote:
>>On second thought, it may be not necessary. You can extract an old commit
>>object, edit it, put it into Git with a new SHA1, and then use the graft file to
>>replace all references from an old to a new one. And you will be able to see
>>changes immediately in gitk.
>
> Hmmmm, interesting thought.  That just might solve my problem.

This script is just a prove of the concept. It seems to work for me, but
I don't really tested it.

===========================================
#!/bin/bash

set -e

# creating some silly repo
git init
# creating some history
for ((i=0; $i<10; i++))
do
	echo foo$i > foo$i
	git add foo$i
	git commit -m "add foo$i"
done

# run gitk to see it
gitk --all &

# dump all graft info to text file
git rev-list --parents --all > .git/info/grafts.tmp
mv .git/info/grafts.tmp .git/info/grafts

# please choose what commit you want to edit
echo
while read -p 'Edit commit: ' C
do
C=$(git rev-parse "$C") || continue
# edit commit C
git cat-file commit $C > .git/COMMIT_OBJ
vim .git/COMMIT_OBJ

C2=$(git hash-object -w -t commit .git/COMMIT_OBJ)

# replace all references from C to C2
sed -e 's/\<'$C'\>/'$C2'/g' < .git/info/grafts > .git/info/grafts.tmp
mv .git/info/grafts.tmp .git/info/grafts
done
===========================================

Dmitry