travis-pyenv

Set up pyenv to use in Travis CI builds.

Setting up pyenv properly in a Travis CI build environment can be quite tricky. This repo contains a script (setup-pyenv.sh) that makes this process much simpler.

A common use case for this is to install an up-to-date version of PyPy. The Travis CI build images currently contain a very old version of PyPy which breaks some common Python modules.

Usage

1. Set the $PYENV_VERSION environment variable to the Python to install.
2. Tell Travis to cache the $HOME/.pyenv_cache directory.
3. Download and source the script in before_install.

There are a few install options that can be set via environment variables:

• PYENV_VERSION The pyenv to install [required]
• PYENV_VERSION_STRING String to fgrep against the output of python --version to validate that the correct Python was installed (recommended) [default: none]
• PYENV_ROOT Directory in which to install pyenv [default: ~/.pyenv]
• PYENV_RELEASE Release tag of pyenv to download [default: clone from master]
• PYTHON_BUILD_CACHE_PATH Directory in which to cache PyPy builds [default: ~/.pyenv_cache]

Example travis.yml

language: python
matrix:
  include:
    - python: '2.7'
    - python: '3.5'
    - python: pypy
      env: PYENV_VERSION=pypy-5.4.1 PYENV_VERSION_STRING='PyPy 5.4.1'
cache:
  - pip
  - directories:
    - ~/.pyenv_cache

before_install:
  - |
      if [[ -n "$PYENV_VERSION" ]]; then
        wget https://github.com/praekeltfoundation/travis-pyenv/releases/download/0.2.0/setup-pyenv.sh
        source setup-pyenv.sh
      fi

script:
  - py.test my_project

Notes

• Installing pyenv by downloading a release tag rather than cloning the git repo can make your builds a bit faster in some cases. Set the PYENV_RELEASE environment variable to achieve that.
• pyenv fails to install properly if ~/.pyenv is present, even if the directory is empty. So if you cache any directories within ~/.pyenv then you will probably break pyenv.