travis-python

Helps to install Python to Travis CI machines on Linux, macOS and Windows.

Usage

You need to source the provided Bash script and call the install_python() function.

Or just use the shared configuration snippet. The easiest way to do it is to import the shared configuration snippet:

import:
  - source: neimad/travis-python:stable.yml
    mode: deep_merge_prepend

⚠️ The imported configuration needs to be prepended and a deep merge is required to be able to use the installed Python distribution in the before_install and subsequent phases.

Read the configuration documentation to understand how it works.

Then, specify the operating systems as usual:

import:
  - source: neimad/travis-python:stable.yml
    mode: deep_merge_prepend

os:
  - linux
  - osx
  - windows

Finally, specify the wanted Python version using the PYTHON environment variable:

import:
  - source: neimad/travis-python:stable.yml
    mode: deep_merge_prepend

os:
  - linux
  - osx
  - windows

env:
  - PYTHON=3.8
  - PYTHON=3.7
  - PYTHON=2

The Python distribution is installed during the before_install phase and available using the python program name (whether it is Python 2 or 3).

Documentation

Some documentation is available.

Why and how ?

To provide a similar Python environment for the three operating systems available on Travis CI, we have to deal with many issues:

• the Python language is only officialy supported on Linux Travis CI machines,
• Python environments use different executables names depending on the OS pointing alternatively to Python 3 or Python 2 executables,
• fetching a specific Python version is challenging: it depends on the OS version and installing a custom Python distribution depends on the packages management system.

To solve those problems, some directions have been taken:

• use python-build from Pyenv to install Python environment on Linux and macOS,
• use Chocolatey to install Python environment on Windows,
• use a Bash script because it is the shell commonly available on all operating systems available on Travis CI,
• use a Bash 3.2 compatible script because it is the one available on macOS,
• use pure Bash functions because external program may differ in behavior depending on the operating system type and version.

Development

The following dependencies are required:

• ShellCheck to lint shell scripts,
• Shellspec to run units tests,
• Bash to run the script,
• Pre-commit to check the changes before committing.

Contributing

If you're facing an issue using travis-python, please look at the existing tickets. Then you may open a new one.

You may also make a pull request to help improve it.

Changelog

See the changelog to see what changes have been made and what you can expect in the next release.

License

travis-python is licensed under the GNU GPL 3 or later.