title: How to add passenv to tox.ini without editing the file but by running tox in virtualenv shell nature script in Jenkins behind proxy (python)
body: <p>I am trying to run python unit tests in jenkins using <code>tox</code>'s virtualenv. I am behind a proxy so I need to pass <code>HTTP_PROXY</code> and <code>HTTPS_PROXY</code> to tox, else it has problems with downloading stuff.</p>
  
  <p>I found out that I can edit <code>tox.ini</code> and add <code>passenv=HTTP_PROXY HTTPS_PROXY</code> under <code>[testenv]</code>, and than using the Create/Update Text File Plugin I can override the tox.ini(as a build step) whenever Jenkins job fetches the original file from repository. This way I can manually copy content of tox.ini from workspace, add the <code>passenv=</code> line below <code>[testenv]</code> and update the file with the plugin mentioned above. But this is not the proper solution. I don't want to edit the tox.ini file this way, because the file is constantly updated. Using this solution would force me to update the tox.ini content inside the plugin everytime it is changed on the git repository and I want the process of running unit tests to be fully automated. And no, <strong>I can't edit the original file on git repository.</strong></p>
  
  <p>So is there a way that I can pass the <code>passenv = HTTP_PROXY HTTPS_PROXY</code> in the Shell nature command? This is how my command in Virtualenv Builder looks like:</p>
  
  <p><code>pip install -r requirements.txt -r test-requirements.txt
  pip install tox
  tox --skip-missing-interpreter module/tests/</code></p>
  
  <p>I want to do something like this: </p>
  
  <p><code>tox --skip-missing-interpreter --[testenv]passenv=HTTP_PROXY HTTPS_PROXY module/tests</code></p>
  
  <p>How to solve this?</p>
  
  <p>NOTE:
  I think there might be a solution with using the {posargs}, but I see that there is a line in the original tox.ini containing that posargs already: <code>python setup.py testr --testr-args='{posargs}'</code> help...</p>