Eli Bendersky: GitHub Actions: first impressions

Workflow configuration

To activate GHA for pycparser, all I had to do is create the following YAML file as .github/workflows/ci.yml in the repository:

name: pycparser-tests
on:
  push:
    branches:
      - master
  pull_request:
    branches:
      - master

jobs:
  build:

    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        python-version: [2.7, 3.6, 3.7, 3.8]
        os: [ubuntu-latest, macos-latest, windows-latest]

    steps:

    - uses: actions/checkout@v2
    - name: Set up Python ${{ matrix.python-version }}
      uses: actions/setup-python@v2
      with:
        python-version: ${{ matrix.python-version }}
    - name: Test
      run: |
        python tests/all_tests.py

Some notes:

• This workflow fires on two kinds of events: pushes to the master branch and PRs to the master branch. Each PR will have an automatic CI run for each change (every new commit pushed).
• It runs in multiple configurations: the cross-product of Python versions and OSes, as specified.
• The run: entry is the command the runs the tests.
• While pycparser doesn't have any dependencies, it's easy to have those too by adding pip install $whatever lines to run: before the actual test execution line.

First impressions

My first impressions of GHA compared to Travis:

• Actions run much faster; the CI jobs schedule pretty much immediately. On Travis you might have to wait for multiple minutes.
• Out-of-the-box Windows and Mac OS option! I couldn't get these with the free Travis variant and had to augment my CI solution for pycparser by running on Windows through AppVeyor. Now I only need to maintain a single CI workflow.
• Travis seems to have better documentation and configurability at this point; while the GHA documentation is comprehensive, it's a bit scattered and harder to follow. This is something I hope will improve over time.

I like what I'm seeing from GHA so far; the ability to set up a CI workflow very easily without bouncing between multiple Web UIs is a blessing, and GHA appears to be a capable, performant platform with a convenient selection of OSes.

I'm still using Travis for some projects and will continue comparing the two over the coming months.