Well... testing distutils2 on Windows has been quite an adventure. When
I ran the test suite before applying the patch, I got a bunch of failures
on all of the Python versions I tested (except the ones that had issues
preventing me from running the tests at all). Only one of the failures
appears to be due to the current issue.

A summary of the problems, broken down by Python version:


[python3 branch]

- 3.3/3.2: Two failures:

   * One in test_command_build_ext..test_finalize_options where the
     library search path erroneously includes some additional directories
     under the Python installation directory. This failure is not fixed
     by the patch; it continues to fail after the patch is applied.

   * One in test_manifest that looks like this:

        FAIL: test_process_template (distutils2.tests.test_manifest.ManifestTestCase)
        ----------------------------------------------------------------------
        Traceback (most recent call last):
          File "C:\Users\Nadeem\Code\distutils2\distutils2\tests\test_manifest.py", line 215, in test_process_template
            self.assertEqual(manifest.files, ['d/b.py', 'd/d/e.py'])
        AssertionError: Lists differ: [] != ['d/b.py', 'd/d/e.py']

    This one is clearly caused by the whole directory separator regex
    snafu we're trying to fix. Applying the patch fixes it, and doesn't
    introduce any new failures.

- 3.1: Same as above, plus a failure in test_util:

        FAIL: test_generate_setup_py (distutils2.tests.test_util.UtilTestCase)
        ----------------------------------------------------------------------
        Traceback (most recent call last):
          File "C:\Users\Nadeem\Code\distutils2\distutils2\tests\test_util.py", line 557, in test_generate_setup_py
            self.assertEqual(out, b'SPAM\n')
        AssertionError: b'SPAM\r\n' != b'SPAM\n'

     Like the test_finalize_options failure, this isn't fixed by the patch.


[default branch]

- 2.7: Before the tests start running, runtests.py crashes with an
       ImportError complaining that it can't find the winreg module.
       AFAIK the registry-handling module in the stdlib is called _winreg
       in 2.x, and was only renamed to winreg in 3.x.

- 2.6: Same as 2.7.

- 2.5: Twenty (20) failures, including the three I get on 3.1, some
       miscellaneous stuff that looks registry-related, and around a
       dozen errors complaining about non-ASCII characters in
       bdist_msi.py's copyright notice. As above, your patch fixes
       the one failure in test_manifest, but none of the others.

- 2.4: Can't run the tests; needs Visual C++ 2003, which (AFAICT) isn't
       freely available.


TL;DR summary: The patch itself looks good, but D2 and Windows currently
don't get along at all.

I'd like to file a separate bug for the unrelated failures - do I do that
here, or does distutils2 have a separate bugtracker/mailing list?