Run Tests workflow (home-assistant-libs/pychromecast)

The Run Tests workflow from home-assistant-libs/pychromecast, explained and optimized by Latchkey.

What it does

This is the Run Tests workflow from the home-assistant-libs/pychromecast repository, a real project running GitHub Actions. It is shown here with attribution under its MIT license.

Below, Latchkey shows a faster, safer version produced by its optimization engine.

The workflow

# This workflow will install Python dependencies, run tests and lint with a single version of Python
# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

name: Run Tests

on:
  push:
    branches: [master]
  pull_request:
    branches: [master]

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v7.0.0
      - name: Set up Python 3.11
        uses: actions/setup-python@v6.3.0
        with:
          python-version: 3.11
      - name: Install dependencies
        run: |
          pip install -r requirements.txt
          pip install -r requirements-test.txt
      - name: Check formatting with ruff
        run: |
          ruff format examples pychromecast --check --diff
      - name: Lint with ruff
        run: |
          ruff check examples pychromecast
      - name: Lint with mypy
        run: |
          mypy examples pychromecast
      - name: Lint with pylint
        run: |
          pylint examples pychromecast
      - name: Lint with rstcheck
        run: |
          rstcheck README.rst

The same workflow, on Latchkey

Estimated ~20% faster on cache hits, plus fewer wasted runs and a safer supply chain. Added and changed lines are highlighted.

# This workflow will install Python dependencies, run tests and lint with a single version of Python
# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
 
name: Run Tests
 
on:
  push:
    branches: [master]
  pull_request:
    branches: [master]
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  build:
    timeout-minutes: 30
    runs-on: latchkey-small
 
    steps:
      - uses: actions/checkout@v7.0.0
      - name: Set up Python 3.11
        uses: actions/setup-python@v6.3.0
        with:
          cache: 'pip'
          python-version: 3.11
      - name: Install dependencies
        run: |
          pip install -r requirements.txt
          pip install -r requirements-test.txt
      - name: Check formatting with ruff
        run: |
          ruff format examples pychromecast --check --diff
      - name: Lint with ruff
        run: |
          ruff check examples pychromecast
      - name: Lint with mypy
        run: |
          mypy examples pychromecast
      - name: Lint with pylint
        run: |
          pylint examples pychromecast
      - name: Lint with rstcheck
        run: |
          rstcheck README.rst
 

What changed

• Run on Latchkey managed runners with one line (runs-on), which apply the fixes below automatically and self-heal transient failures. This example uses latchkey-small; pick the runner size that fits the job.
• Cancel superseded runs when a branch or PR gets a newer push.
• Cache dependency installs on the setup step so they are served from cache.
• Add a job timeout so a hung step cannot burn hours of runner time.

What Latchkey heals here

This workflow has steps that commonly fail on transient issues (network, registries, flaky browsers). On Latchkey managed runners they are detected, retried, and self-healed instead of failing your build:

• Dependency installs

This workflow runs 1 job per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow