Report coverage workflow (john-hen/Flake8-pyproject)

The Report coverage workflow from john-hen/Flake8-pyproject, explained and optimized by Latchkey.

What it does

This is the Report coverage workflow from the john-hen/Flake8-pyproject 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

# Report code coverage to Codecov.

name: Report coverage


on: [push, workflow_dispatch]


jobs:

  coverage:

    runs-on: ubuntu-latest


    strategy:
        matrix:
            python: ['3.10', '3.14']


    steps:
      - name: Check out code.

        uses: actions/checkout@v7


      - name: Set up Python.

        uses: actions/setup-python@v6

        with:
            python-version: ${{ matrix.python }}

            allow-prereleases: true


      - name: Install project.

        run:  pip install --editable .[dev]


      - name: Measure code coverage.

        run:  pytest --cov --cov-report=xml


      - name: Upload coverage report.

        uses: codecov/codecov-action@v7

        with:
          token: ${{ secrets.CODECOV_TOKEN }}

          fail_ci_if_error: true

          files: ./build/coverage/coverage.xml

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.

# Report code coverage to Codecov.

name: Report coverage



on: [push, workflow_dispatch]



concurrency:

  group: ${{ github.workflow }}-${{ github.ref }}

  cancel-in-progress: true



jobs:



  coverage:



    runs-on: latchkey-small



    strategy:

        matrix:

            python: ['3.10', '3.14']



    steps:

      - name: Check out code.

        uses: actions/checkout@v7



      - name: Set up Python.

        uses: actions/setup-python@v6

        with:

          cache: 'pip'

            python-version: ${{ matrix.python }}

            allow-prereleases: true



      - name: Install project.

        run:  pip install --editable .[dev]



      - name: Measure code coverage.

        run:  pytest --cov --cov-report=xml



      - name: Upload coverage report.

        uses: codecov/codecov-action@v7

        with:

          token: ${{ secrets.CODECOV_TOKEN }}

          fail_ci_if_error: true

          files: ./build/coverage/coverage.xml

 

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.

1 third-party action is referenced by a movable tag. Pin it to the commit SHA (Latchkey resolves and applies this automatically) so a repointed tag cannot change what runs.

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 (2 with the matrix expanded) per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow