Alex Alex -4 years ago 92
Python Question

How to fix error “Expected version spec in …” using pip install on Windows?

On a Windows 7 machine I am using the following command to install a package from a local directory:

pip install addons/pnc_tests --upgrade --extra-index-url=http://some_server/simple

which results in the following error:

C:\Users\alex\PNC\tas\ENV\Scripts\ run on 07/16/14 07:50:47

Traceback (most recent call last):
File "C:\Users\alex\PNC\tas\ENV\lib\site-packages\pip\", line 122, in main
status =, args)
File "C:\Users\alex\PNC\tas\ENV\lib\site-packages\pip\commands\", line 258, in run
InstallRequirement.from_line(name, None))
File "C:\Users\alex\PNC\tas\ENV\lib\site-packages\pip\", line 173, in from_line
return cls(req, comes_from, url=url, prereleases=prereleases)
File "C:\Users\alex\PNC\tas\ENV\lib\site-packages\pip\", line 71, in __init__
req = pkg_resources.Requirement.parse(req)
File "C:\Users\alex\PNC\tas\ENV\lib\site-packages\pip\_vendor\", line 2667, in parse
reqs = list(parse_requirements(s))
File "C:\Users\alex\PNC\tas\ENV\lib\site-packages\pip\_vendor\", line 2605, in parse_requirements
line, p, specs = scan_list(VERSION,LINE_END,line,p,(1,2),"version spec")
File "C:\Users\alex\PNC\tas\ENV\lib\site-packages\pip\_vendor\", line 2573, in scan_list
raise ValueError("Expected "+item_name+" in",line,"at",line[p:])
ValueError: ('Expected version spec in', 'addons/pnc_tests', 'at', '/pnc_tests')

How to solve this problem?

Answer Source

One need to replace the slash (/) by a backslash (\):

pip install addons\pnc_tests --upgrade --extra-index-url=http://some_server/simple
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