Control the pip version in virtualenv

Question

How do I control the version of pip which is used in a freshly created venv?

By default, it uses a vendored pip distribution which may be out of date or unsuitable for whatever other reason. I want to be able to create a venv with a user-specified version of pip installed initially, as opposed to creating one and then upgrading the pip installation from within the env.

Answer 1

For me, I just upgraded pip/virtualenv/virtualenvwrapper on my machine (not inside the virtualenv). Subsequently created virtualenvs had the updated version.

deactivate pip install --upgrade pip virtualenv virtualenvwrapper mkvirtualenv ... 

Answer 2

From reading the source of virtualenv, it looks like pip is installed from a source tarfile included with virtualenv. In virtualenv 1.10.1, it is pip-1.4.1.tar.gz in the site-packages/virtualenv_support directory (it gets setuptools from the same place). You could feasibly replace that archive to control the version; virtualenv.py, at least the version I have, doesn't care which version of pip is there:

    if not no_pip:         install_sdist('Pip', 'pip-*.tar.gz', py_executable, search_dirs) 

You could also pass the --no-pip option and then install the version you want from source.

In virtualenv 1.11, it looks for a wheel file (e.g. pip-*.whl) instead of a tar.gz, but other than that it acts the same way (thanks @wim for the update).