Re: Joining Repositories

[Petr Baudis <pasky@suse.cz>]

  Hello,

Dear diary, on Wed, Jan 18, 2006 at 01:25:59PM CET, I got a letter
where Mathias Waack <Mathias.Waack@rantzau.de> said that...
> we're using git with cogito as a frontend. For some reasons I forgot we have 
> some repositories which belong to the same project. To simplify the whole 
> thing I would like to join these repositories. It mainly means to move some 
> directories. So lets say I have: 
> 
> 	/r1/.git
> 	/r2/.git
> 
> and what I would like to have is
> 
> 	/r/.git
> 	   r1
>            r2
> 
> Of course the history should remain (otherwise it would be to easy). 
> 
> How should I do this?

  The crucial question is what the joined repository's directory
structure should be. If from r1/a, r2/b you want r/a, r/b then it's
easy:

	cd r1
	cg-branch-add r2 ../r2/.git
	cg-fetch r2
	cg-merge -j r2

  But if you want r1/a, r2/b to turn to r/r1/a, r/r2/b, you will have
to rewrite the history of each (and then do the above). One rough
and untested sketch...

	mkdir r1-rewritten
	cd r1-rewritten
	cp -a ../r1/.git .
	for commit in $(git-rev-list --topo-order HEAD | tac); do
		git-read-tree --prefix=r1/ $commit
		# here, setup the AUTHOR/COMMITTER variables
		# appropriately (you can look at cg-commit's
		# $copy_commit handler)
		git-cat-file commit "$commit" | sed -e '1,/^$/d' | \
			git-commit-tree $(git-write-tree) \
				$(for parent in $(cg-object-id -p $commit); do
					cat commitmap/$parent
				  done) >commitmap/$commit
		last_commit=$commit
	done
	git-update-ref HEAD $(cat commitmap/$last_commit)

-- 
				Petr "Pasky" Baudis
Stuff: http://pasky.or.cz/
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