tox-pip-version 0.0.7

Select PIP version to use with tox

[](https://travis-ci.com/pglass/tox-pip-version)  

Overview

This is a tox plugin that preinstalls a specific version of pip in each tox environment.

`bash pip install tox-pip-version `

This works around the default behavior of tox/virtualenv that always installs the latest version pip. It is an improvment over the VIRTUALENV_NO_DOWNLOAD=1 option that does not install the latest version, but could result in usage of an outdated version of pip.

Recommendation: Do not pin the pip version long term. You get more stable repeatable builds, but at the cost of using an outdated (possibly vulnerable) package. This should be used as a temporary fix for breakages in upstream pip, or in conjunction with a regular process to update the version pin.

Note: This relies on an [unstable tox plugin interface]( https://tox.readthedocs.io/en/latest/plugins.html#tox.hookspecs.tox_testenv_create). You may experience breakage with new tox versions. If you do, please feel free to [report the issue](https://github.com/pglass/tox-pip-version/issues/new) on Github.

### Usage

Install the package and include pip_version in your tox.ini

`tox [testenv] pip_version = pip==19.0.1 `

Or, set the TOX_PIP_VERSION environment variable,

`bash export TOX_PIP_VERSION=18.1 tox `

The plugin will install that version of pip into the tox-created virtualenv, just after tox creates the virtualenv, but before dependencies are installed.

The pip_version within tox.ini, if present, is always used over the environment variable.

If neither pip_version or TOX_PIP_VERSION is present, the plugin does nothing.

### Version Sets

Version sets/ranges are supported, enabling installation of a version of pip matching a set of specifiers. There are two basic formats: a plain version number, or the package name with optional [PEP440-compatible]( https://www.python.org/dev/peps/pep-0440/#version-specifiers) version specifiers.

tox.ini | effective pip command |

—————————- | —————————- |

pip_version = 19.0 | pip install -U pip==19.0 |

pip_version = pip==19.0 | pip install -U pip==19.0 |

pip_version = pip>=19.0 | pip install -U pip>=19.0 |

pip_version = pip!=19,>18 | pip install -U pip!=19,>18 |

pip_version = pip | pip install -U pip |

### Tests

Use make test to run the tests, which includes linting and functional tests.

Each of the tests/* directories is a “feature” that needs testing. Each feature sub-directory contains a tox.ini file that sets pip version in a particular way, and then uses a tox command to check the correct pip version was installed.