What is the best way to handle branches of vendor branches in SVN?

Question

So, I'm already familiar with this:
http://svnbook.red-bean.com/en/1.5/svn.advanced.vendorbr.html

My question is how do you handle a vendor branch that has both a stable release and an alpha/beta branch that you want to integrate?

So, say you follow the original example from the SVN book. You'd have:

svn://localhost/home/svn/vendor/libcomplex/current
svn://localhost/home/svn/vendor/libcomplex/1.0
svn://localhost/home/svn/vendor/libcomplex/1.1 (same as current)

Now, say you have two versions of your own 'calc' app:

calc (this is essentially trunk == calc 2.0)
calc-1.0 (released to public)

Let's say calc-1.0 uses libcomplex 1.0 and calc (in trunk) used libcomplex 1.1, which is still being developed.

There's a bug in libcomplex 1.0 and a new version is released to fix that bug: libcomplex 1.0.1. The libcomplex maintainers have also included this bugfix into libcomplex 1.1.

You're not ready to release calc 2.0, so you need to integrate libcomplex 1.0.1 into your vendor branch and then update calc-1.0 to make a bug-fix release.

Where does it go?

You can't put it at svn://localhost/home/svn/vendor/libcomplex/current because 1.1 currently lives there.

Do you copy svn://localhost/home/svn/vendor/libcomplex/1.0 to svn://localhost/home/svn/vendor/libcomplex/1.0.1 and then bring in the new release? That way you could use svn to merge the diff between 1.0 and 1.0.1 to calc-1.0.

Answer 1

The recommended practice is to create a branch for your release. That way, it doesn't matter what changes you make in trunk to your vendor folders. You can then update the 1.0 release branch with the 1.0.1 version of libcomplex, and that would not have affected trunk (calc 2.0).

This won't work if calc 1.0 and calc 2.0 live side by side in the same branch however.

The next thing to do is to not have "current". Just refer directly to the version that you are using. eg, leave your folder structure as:

vendor/libcomplex/1.0
vendor/libcomplex/1.1
vendor/libcomplex/1.0.1

and never overwrite these files. Then calc 2.0 can refer to version 1.1 of libcomplex, and calc 1.0 can refer to 1.0.1.

Your last option, (and not really recommended), is to use svn tags (see complex tags). They allow you to mix and match versions, so you could technically create a tag to represent the patch release of your calc 1.0 with the old version of libcomplex.