tox doesn't work with older pip versions like 1.4.1

[pytoxbot]

• Bitbucket: https://bitbucket.org/hpk42/tox/issue/228
• Originally reported by: @malemburg
• Originally created at: 2015-03-11T21:22:01.512

When running bin/tox with pip 1.4.1 (and pyrun) you get:

Could not run 'bin/tox': No module named req_file

Looking into the code, this line is causing it:

lib/python2.7/site-packages/tox/_config.py:
-- from pip.req.req_file import parse_requirements

The current pip does come with a req_file module. It was added in Jan 2014 and released in version 6.0 of pip.

The setup.py of tox does not define a dependency on pip:

https://bitbucket.org/hpk42/tox/src/aa5b7ce560ca7cc27ed609fad8d2678a9e6836ac/setup.py?at=default

I guess it would be good to define the minimum version with which tox works.

[pytoxbot]

Original comment by @theMarix

Works fine for us now. Thanks!

[pytoxbot]

Original comment by @malemburg

Right, I was testing the version Holger had asked to test. With the released version, everything works fine - even with pip 1.4.1. Thanks.

[pytoxbot]

Original comment by mriedem

Yup, works for me, thanks for turning this around so quickly!

[pytoxbot]

Original comment by @cedk

@malemburg It doesn't seem you are installing the released 1.9.2 version
The final fix was not to add a dependency to pip but to backout the new functionality that depended on it.

[pytoxbot]

Original comment by @malemburg

Doesn't seem to help:

#!python

tmp/test-tox-2> bin/pip install https://devpi.net/hpk/dev/+f/fb2/4aa9fdf22e2a6/tox-1.9.2.dev2.tar.gz
...
tmp/test-tox-2> bin/tox
Traceback (most recent call last):
  File "bin/tox", line 8, in <module>
    load_entry_point('tox==1.9.2.dev2', 'console_scripts', 'tox')()
  File
"/home/lemburg/tmp/test-tox-2/lib/python2.7/site-packages/setuptools-0.6c11-py2.7.egg/pkg_resources.py",
line 318, in load_entry_point
  File
"/home/lemburg/tmp/test-tox-2/lib/python2.7/site-packages/setuptools-0.6c11-py2.7.egg/pkg_resources.py",
line 2221, in load_entry_point
  File
"/home/lemburg/tmp/test-tox-2/lib/python2.7/site-packages/setuptools-0.6c11-py2.7.egg/pkg_resources.py",
line 1954, in load
  File "/home/lemburg/tmp/test-tox-2/lib/python2.7/site-packages/tox/__init__.py", line 23, in <module>
    from tox._cmdline import main as cmdline  # noqa
  File "/home/lemburg/tmp/test-tox-2/lib/python2.7/site-packages/tox/_cmdline.py", line 15, in <module>
    from tox._venv import VirtualEnv
  File "/home/lemburg/tmp/test-tox-2/lib/python2.7/site-packages/tox/_venv.py", line 6, in <module>
    from tox._config import DepConfig
  File "/home/lemburg/tmp/test-tox-2/lib/python2.7/site-packages/tox/_config.py", line 13, in <module>
    from pip.download import PipSession
ImportError: cannot import name PipSession

I had pip 1.4.1 installed and would have expected tox to upgrade this
to pip 6.0

[pytoxbot]

Original comment by @hpk42

• backout ability that --force-deps substitutes name/versions in
  requirement files due to various issues.
• This fixes issue228, fixes issue230, fixes issue231
  which popped up with 1.9.1.
• bump to 1.9.2 version

→ <<cset 452288d6c500>>

[pytoxbot]

Original comment by @hpk42

could some of you try pip install https://devpi.net/hpk/dev/+f/fb2/4aa9fdf22e2a6/tox-1.9.2.dev2.tar.gz and see if it works within your environments? I think the problem was simply that we need to import from pip.req instead of pip.req.req_file. cc @sontek

[pytoxbot]

Original comment by vladimir-lu-work

I've raised an issue against Jenkins: https://issues.jenkins-ci.org/browse/JENKINS-27551

[pytoxbot]

Original comment by @cedk

I submitted the pull request #139

[pytoxbot]

Original comment by mriedem

+1, just started hitting this today in our CI with the tox 1.9.1 release.

[pytoxbot]

Original comment by @cedk

I agree this is a very annoying issue when using tox for CI.

[pytoxbot]

Original comment by @theMarix

I also ran into this issue. Tox 1.9.1 has a code dependency on pip>=6.0 which is not declared in the package dependencies. Please fix this, as it causes surprising failures and forces us to add unnecessary additional set-up logic to our CI environment.

Note that this requirement does not exist for tox 1.9.0, which in my opinion violates semantic versioning.