This is a good idea. It's probably helpful for stable parallel test execution. (
However, -1 for patch v001. This would fail on Windows. The path strings constructed for the files would not be valid URI syntax due to the drive spec. There is a point in the tests where the path strings are converted back to a URI, and this causes an exception to be thrown.
I took the liberty of making a small tweak and verifying that it passes on Mac and Windows. I'm attaching it as v002.
Thanks, Colin P. McCabe! Maybe another committer can review and +1, since I have sullied myself by touching the patch?