Black format check workflow (Textualize/textual)

The Black format check workflow from Textualize/textual, explained and optimized by Latchkey.

What it does

This is the Black format check workflow from the Textualize/textual 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

name: Black format check

on:
  pull_request:
    paths:
      - '.github/workflows/black_format.yml'
      - '**.py'

jobs:
  black-format-check:
    runs-on: "ubuntu-latest"
    steps:
      - uses: actions/checkout@v3.5.2
      - name: Set up Python 3.11
        uses: actions/setup-python@v4.6.0
        with:
          python-version: 3.11
      - name: Install black
        run: python -m pip install black==24.1.1
      - name: Run black
        run: black --check src

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.

 
name: Black format check
 
on:
  pull_request:
    paths:
      - '.github/workflows/black_format.yml'
      - '**.py'
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  black-format-check:
    timeout-minutes: 30
    runs-on: "ubuntu-latest"
    steps:
      - uses: actions/checkout@v3.5.2
      - name: Set up Python 3.11
        uses: actions/setup-python@v4.6.0
        with:
          cache: 'pip'
          python-version: 3.11
      - name: Install black
        run: python -m pip install black==24.1.1
      - name: Run black
        run: black --check src
 

What changed

• Cancel superseded runs when a branch or PR gets a newer push.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