The patch appears fine but it really doesn't have anything to do with the gist of this issue.  The problem remains that much of macpath is fundamentally broken.  In the intervening years since the issue was opened, I contend that any need for OS 9 style paths (aka HFS paths) has diminished even further so I would still support starting in Python 3.5 the deprecation and removal process for this module.  But, as long as it remains, to address the current problems at a minimum a patch would be needed to remove or raise exceptions for all of the macpath functions that make file system calls and to update the documentation.