Importing one git repo as a branch into another git repo

Question

For historic reason we have source code for different version in different git repositories. So while Project A holds the version X of the source Project B holds version Y of the source.

Do you guys know a way to import Project B as a branch of Project A?

Thanks

Answer 1

This is simple with Git. You have to add project B as remote, then fetch:

git remote add projectB git://url.to/projectB.git
git fetch projectB

Answer 2

I am not sure, what you mean by "git project". In git the states of source code are described by commits (a.k.a. revisions). These are stored in repositories, but are independent of the them and can be copied between repositories freely. In fact, to work on the sources git always copies the commits to your local repository that lives in the .git directory of your working copy. Branches are just names pointing to commits.

So if you have some branches in one repository and other branches in another repository, you can:

1. Pull both into your local working repository:

   git remote add B git://url.to/project.B.git
   git fetch B
   

2. Base your work on branches from B

   git checkout -b newname remotes/B/branchname
   

3. Push the branches you got from one central repository to the other:

   git push origin remotes/B/branchname:branchname
   

   or the other way around

   git push B remotes/origin/master:othername
   

You can omit the remotes/ prefix most of the time.