This seems to have converted a test from dos to unix style. I'm not sure if that was intentional, or if this feature is still a WIP. (Sorry, I've been busy lately, and haven't had time to follow this closely)
It wasn't intentional, and it took me a while to figure out why it changed, but I'm pretty confident it's just changed in the tests, since the test runner sets `ui.slash`. The old code called `m.uipath()` and that called `util.pathto()`. The new code calls `repo.path()`, which calls `dirstate.pathto()`, which also calls `util.pathto()`. However, if `ui.slash` is set, `dirstate.pathto()` also calls `util.pconvert()` to convert it back to a slash-separated path. Please send a patch to update the test case if you have access to a Windows machine.