是否有可能在Github上合并和链接两个未链接的回购？

Question

I have a repo on Github that was imported from Google Code (actually, someone else imported it and I forked it). The original project has been dormant on Google Code since 2011. The code is mostly in a single file in the root directory. My fork has the Google Code history. We've made additions to the code.

A third person has also imported the original source to Github, and made changes. Someone forked that and added some more.

(There are other similar Google Code->Github clones, so it might be useful to do something similar with some of those too.)

I would like to somehow unify these, I'd like:

• to merge the other repo's changes into mine, and
• to keep the history of their commits.

Ideally, I'd also like:

• somehow link each repo, perhaps so their network graph's are linked (on Github), and
• allow future PRs to be made easily between forks.

So:

1. What's the best way to do this?
2. Is the second part even possible?
3. If not, what's the best way around it?

Answer 1

Regarding the mercurial repo, you can start by converting it to Git ( fast-export/hg-fast-export.sh ).

And regarding the possibility to link two different histories (for two branches of unrelated repo), you can use git grafts (graft point) to make a common history.

See for instance " How to rebase one Git repository onto another one? " ( .git/info/grafts + git filter-branch ).