Re: How to combine git repos with similar code and keep all branches and tags?

[Junio C Hamano <gitster@pobox.com>]

Matthieu Moy <Matthieu.Moy@grenoble-inp.fr> writes:

> Jose de Leon <jdeleon@ensim.com> writes:
>
>> For some unknown reason to me, our developers started a git project,
>> called Ver1, this was the first version. Then sometime later, they
>> created a new git repository called Ver2, the initial commit for Ver2
>> was essentially a copy of the code in Ver1 from the master. They
>> didn't clone it, they just copied the code at the latest point.
>
> This is why "graft points" were created, and then superseeded by "git
> replace".
>
> See http://git-scm.com/blog/2010/03/17/replace.html and
> http://git-scm.com/docs/git-replace

After setting up either grafts or replaces, I'd strongly recommend
running filter-branch or bfg to rewrite the history of the combined
result, and have the developers use that rewritten history _after_
removing the grafts (or replaces).

And if you are going to go that route, then graft is sufficient and
a lot more light-weight.  The only advantage replace has over grafts
is that they can be transferred using "git push" and "git fetch"
(while grafts can be transferred with some file transfer mechanism
outside Git) but if you are rewriting the history, that advantage is
lost.