test_expanduser in test.test_posixpath.PosixPathTest fails when the users $HOME being exactly "/", after the patch in issue17809 was introduced.

test test_posixpath failed -- Traceback (most recent call last):
  File "/build/python/src/Python-3.5.0rc2/Lib/test/test_posixpath.py", line 249, in test_expanduser
    self.assertEqual(posixpath.expanduser("~"), home.rstrip("/"))
AssertionError: '/' != ''
- /
+

Would it be appropriate to apply the rstrip() also to the left part of the equation?

btw, there seems to be a relevant failure in test_pathlib as well:

test test_pathlib failed -- Traceback (most recent call last):
  File "/build/python/src/Python-3.5.0rc2/Lib/test/test_pathlib.py", line 2015, in test_expanduser
    self.assertEqual(p1.expanduser(), P(userhome) / 'Documents')
AssertionError: PosixPath('/Documents') != PosixPath('Documents')

(not sure if they are really relevant, though)

For posixpath the fix is straightforward: just skip that assert if the home ends up being '/' (the '/' is tested above).

For pathlib, I'm not entirely sure what the fix should be.

Here is the patch that addresses the issue in both tests. Felix, could you test it?

What if HOME is "//"?

> What if HOME is "//"?

Is this possible? What would be the result of these tests? Would they fail? As far as I understand my patch is just fixing problem introduced by fixes from issue 17809.

Yet one corner case is empty HOME value.

New changeset 194b356c84f5 by Serhiy Storchaka in branch '3.5':
Issue #24950: Fixed expanduser tests when the users home directory in pwd is "/".
https://hg.python.org/cpython/rev/194b356c84f5

New changeset b9b99cb85a5f by Serhiy Storchaka in branch 'default':
Issue #24950: Fixed expanduser tests when the users home directory in pwd is "/".
https://hg.python.org/cpython/rev/b9b99cb85a5f