test_os.py 文件源码

def test_exist_ok_s_isgid_directory(self):
        path = os.path.join(support.TESTFN, 'dir1')
        S_ISGID = stat.S_ISGID
        mode = 0o777
        old_mask = os.umask(0o022)
        try:
            existing_testfn_mode = stat.S_IMODE(
                    os.lstat(support.TESTFN).st_mode)
            try:
                os.chmod(support.TESTFN, existing_testfn_mode | S_ISGID)
            except PermissionError:
                raise unittest.SkipTest('Cannot set S_ISGID for dir.')
            if (os.lstat(support.TESTFN).st_mode & S_ISGID != S_ISGID):
                raise unittest.SkipTest('No support for S_ISGID dir mode.')
            # The os should apply S_ISGID from the parent dir for us, but
            # this test need not depend on that behavior.  Be explicit.
            os.makedirs(path, mode | S_ISGID)
            # http://bugs.python.org/issue14992
            # Should not fail when the bit is already set.
            os.makedirs(path, mode, exist_ok=True)
            # remove the bit.
            os.chmod(path, stat.S_IMODE(os.lstat(path).st_mode) & ~S_ISGID)
            with self.assertRaises(OSError):
                # Should fail when the bit is not already set when demanded.
                os.makedirs(path, mode | S_ISGID, exist_ok=True)
        finally:
            os.umask(old_mask)