I left a comment on Rietveld.  Also, the test doesn't pass on Windows:

test test_unittest failed -- Traceback (most recent call last):
  File "C:\Data\code\CPython\hg.python.org\devinabox\cpython\lib\unittest\test\t
est_discovery.py", line 677, in test_command_line_handling_do_discovery_calls_lo
ader
    self.assertEqual(Loader.args, [('.', "'test*.py'", None)])
AssertionError: Lists differ: [('.', 'test*.py', None)] != [('.', "'test*.py'",
None)]

First differing element 0:
('.', 'test*.py', None)
('.', "'test*.py'", None)

- [('.', 'test*.py', None)]
+ [('.', "'test*.py'", None)]
?        +          +