'C{FilePath.makedirs} throws an C{OSError} exception
when called on a directory that already exists.'

def test_makedirsThrowsWithExistentDirectory(self):

    fp = filepath.FilePath(os.path.join(self.mktemp()))
    fp.makedirs()
    exception = self.assertRaises(OSError, fp.makedirs)
    self.assertEqual(exception.errno, errno.EEXIST)
