The module backports features to Python 2.6 and 2.7. If it is available,
the tests will use it. If it is not available, it will fall back to
regular unittest. On Python 2.7, the tests pass anyway. On Python 2.6,
there are failures with Python 2.6.
Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>
Instead of spawning `cp x/* y` there is now Python code to the same
thing. This should help with debugging if something fails as the
traceback will be more informative (rather than saying a command
failed). As another benefit the tests get much simpler.
Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>