Importing branches

[philpem]

Can git-cc be made to import branches and merges (hyperlink data) from Clearcase?

At the moment it seems I can either:
Specify "branches=release" and get all the "merge of branch foo into release" changesets, or
Specify "branches=*" and get every single Clearcase commit mashed into multiple commits on the git master branch (with no branching/merging imported)

What I'd like is to have Clearcase branches (the feature/bugfix branches) and merge hyperlinks (where said branches have been brought into the release tree) imported into Git so I can see how the code has changed over time.

[charleso]

Hi Phil,

I'm afraid not. As you've discovered the branches configuration will basically filter the commits into a single git branch. Things in Clearcase get very complicated when you start talking about merging largely because it doesn't have the concept of an atomic commit. I wish I could have got this working as you've described; believe me when I say I spent a fair bit of time thinking about it. The closest I got was in the Java version of git-cc which I wrote just at the end of my Clearcase days.

This is the file/branch in question (the cleartool branch only):

https://github.com/charleso/gitcc4j/blob/cleartool/ClearGit/src/gitcc/cmd/Rebase.java

I used this version to import our repository into Git as part of a final migration (which is why I don't work on git-cc any more). Part of the problem was that I used 'git merge --strategy=ours' to fake the merges, and the history was all messed up as a result.

If you're familiar with Java that might be a good place to start, otherwise I'm afraid there isn't much you can do. There is also the Clearvision import tool, but that comes at a price. :(

Cheers,

Charles

[philpem]

That's fair enough -- I'm trying out a two-step approach now - Polarion's Clearcase-to-Subversion translator apparently supports branches so I'm using that, then converting the SVN repository to Git.

Perhaps a little convoluted but hopefully it'll do what I need :)

Thanks,
Phil.

[charleso]

Ahh, I'd forgotten about that. I remember looking at that back when I first stated. If it does branches properly then that's a much better option. If it does, please let me know so I can recommend it to other people.

Good luck.

Charles