Description of problem:

os.path.relpath(path[, start]) returns incorrect result, when the 'start' argument is set to '/'.

Version-Release number of selected component (if applicable):

python-2.7-8.fc14.1.x86_64

Actual results:

# python2.7
Python 2.7 (r27:82500, Sep 16 2010, 18:02:00) 
[GCC 4.5.1 20100907 (Red Hat 4.5.1-3)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.path.relpath("/etc/passwd", "/")
'../etc/passwd'
>>> os.path.relpath("/etc/passwd", "/root")
'../etc/passwd'
>>> 


Expected results (python-2.7.1-7.fc16.x86_64):

# python2.7
Python 2.7.1 (r271:86832, Apr 12 2011, 16:12:28) 
[GCC 4.6.0 20110331 (Red Hat 4.6.0-2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.path.relpath("/etc/passwd", "/")
'etc/passwd'
>>> os.path.relpath("/etc/passwd", "/root")
'../etc/passwd'
>>>


Additional info:

http://bugs.python.org/issue5117