git newbie error - how to recover

Question

Possibly related to http://stackoverflow.com/questions/286988/git-pulling-changes-from-clone-back-onto-the-master

I was working on an ASP.NET project when I discovered I needed to make an "experimental" set of changes which may or may not have been required in the production version.

The obvious thing to do was to create a branch.

However as I was familiar with darcs and svn but not git, I assumed that a clone was the "normal" way to create a branch (I now know that git branch would have been more appropriate.)

I continued to work on the experimental change in the clone and, at the same time, other changes in the original repository.

Since then I have discovered that the experimental changes are desirable in the production version and would like to merge the two change sets.

If I had originally done a branch instead of a clone, this would be trivial. I'm sure it's not too hard to merge between separate repositories, but having looked through the docs I don't think it can be done with a single command (a simple pull does not work.)

I haven't (yet) explicitly configured one repository as a "remote" of the other, but I am guessing this will be part of the solution.

The upstream repository at the time did not use any VCS - it was just a directory full of zips with version numbers appended to the file names.

So I would like to know:

• What's the easiest way to merge the change sets across repositories? (I don't expect any major conflicts.)
• Just how harmful is it to clone instead of branching? Have I lost any information by doing this, e.g. shared history, common dependencies?

Answer 1

In your original "un-branched" git repository, run these commands:

git remote add name_it_anything /path/to/the/other/git/repository
git fetch name_it_anything
git merge name_it_anything/master

That will merge inn all the changes in nname_it_anything. If you don't want all of them, but just a selection of the commits, you can git log name_it_anything/master to see the list of commits and then git cherry-pick [SHA] for each of the commits you want to merge.

Answer 2

I think you can git-format-patch in one repository, and then apply in another. This way all important information is preserved.

Answer 3

Regarding the second part of your question:

Just how harmful is it to clone instead of branching? Have I lost any information by doing this, e.g. shared history, common dependencies?

Git is a distributed version control system. The whole point of a DVCS is to be able to merge changes back and forth between different repositories.