So, I'm working with an open source project, and I'm making some significant changes to a small module of the project. The project uses SVN as its version control, and I need access to this repository, since there is a lot of active development, and I need to be able to get the updates. At the same time, I don't want to commit my changes to the repository until I've finished and tested it, as well as passing the patch file around for comments. I would also like to have my own repository, so that I can have access to version control capabilities, but I don't want to use the SVN repository, since I'd like to keep my changes out of the main branch until it's done. To make things slightly easier, I will not be modifying anything that is currently in the SVN repository, only adding new files.
The only way I've thought of doing this so far is to use SVN to track the existing files, and use Mercurial, CVS, Git, or some other version control to track my new files, so in the directory I'm working in, I'd have both a .svn and .hg folder. This is kind of a hassle, though.
Does anyone have any other suggestions for how to do this?