I've got a simple class that gets most of its arguments via init, which also runs a variety of private methods that do most of the work. Output is available either through access to object variables or public methods.

Here's the problem - I'd like my unittest framework to directly call the private methods called by init with different data - without going through init.

What's the best way to do this?

So far, I've been refactoring these classes so that init does less and data is passed in separately. This makes testing easy, but I think the usability of the class suffers a little.