Behavior difference for os.path.split

[c1728p9]

Describe the bug
On windows, the function python version of os.path.split does not convert path separators, while the pyfakefs version does. Is this intentional or is this a bug?

How To Reproduce

import os
import unittest
from pyfakefs.fake_filesystem_unittest import TestCase


class TestPathSplit(TestCase):

    def test_split(self):
        head_before, tail_before = os.path.split('/')
        self.setUpPyfakefs()
        head_after, tail_after = os.path.split('/')
        print("Before setUpPyfakefs head=%s, tail=%s" % (head_before, tail_before))
        print("After  setUpPyfakefs head=%s, tail=%s" % (head_after, tail_after))
        self.assertEqual(head_before, head_after)

if __name__ == '__main__':
    unittest.main()

>test.py          
Before setUpPyfakefs head=/, tail=
After  setUpPyfakefs head=\, tail=
F
======================================================================
FAIL: test_split (__main__.TestPathSplit)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\Users\Russ\Desktop\backup-tool\bug-report\test.py", line 14, in test_split
    self.assertEqual(head_before, head_after)
AssertionError: '/' != '\\'
- /
+ \

Your environment

>python -c "import platform; print(platform.platform())"
Windows-10-10.0.19041-SP0

>python -c "import sys; print('Python', sys.version)"
Python 3.9.1 (tags/v3.9.1:1e5d33e, Dec  7 2020, 17:08:21) [MSC v.1927 64 bit (AMD64)]

>python -c "from pyfakefs.fake_filesystem import __version__; print('pyfakefs', __version__)"
pyfakefs 4.5.0

[mrbean-bremen]

Thanks - no, that is not intentional.

[mrbean-bremen]

Shall be fixed in master now, please check!

[c1728p9]

@c1728p9 I gave this a try today with the tip of master (e06472b) and can confirm that this fixes the problem I was seeing. Thanks for the quick fix!