This GitHub Action posts your test suite's LCOV coverage data to coveralls.io for analysis, change tracking, and notifications. You don't need to add the repo to Coveralls first, it will be created when receiving the post.

When running on pull_request events, a comment will be added to the PR with details about how coverage will be affected if merged.

The action's step needs to run after your test suite has outputted an LCOV file. Most major test runners can be configured to do so; if you're using Node, see more info here.

• coveralls-api-response: JSON response from the Coveralls API with a status code and url for the Job on Coveralls.

• This example assumes you're building a Node project using the command make test-coverage, demo here: nickmerwin/node-coveralls

  on: ["push","pull_request"]

  name: Test Coveralls

  jobs:

    build:
      name: Build
      runs-on: ubuntu-latest
      steps:

      - uses: actions/checkout@master

      - name: Use Node.js 10.x
        uses: actions/setup-node@master
        with:
          version: 10.x

      - name: npm install, make test-coverage
        run: |
          npm install
          make test-coverage

      - name: Coveralls
        uses: coverallsapp/github-action@master
        with:
          github-token: ${{ secrets.github_token }}

  on: ["push","pull_request"]

  name: Test Coveralls Parallel

  jobs:

    build:
      name: Build
      runs-on: ubuntu-latest
      steps:

      - uses: actions/checkout@master

      - name: Use Node.js 10.x
        uses: actions/setup-node@master
        with:
          version: 10.x

      - name: npm install, make test-coverage
        run: |
          npm install
          make test-coverage

      - name: Coveralls Parallel
        uses: coverallsapp/github-action@master
        with:
          github-token: ${{ secrets.github_token }}
          parallel: true
          path-to-lcov: ./coverage/lcov.info # optional (default value)

      - name: Coveralls Finished
        uses: coverallsapp/github-action@master
        with:
          github-token: ${{ secrets.github_token }}
          parallel-finished: true

The "Coveralls Finished" step needs to run after all other steps have completed; it will let Coveralls know that all jobs in the build are done and aggregate coverage calculation can be calculated and notifications sent.

1. A new function f without test coverage is added.
2. The changes are committed and pushed to a new branch "function/f"
3. The Action runs on GitHub CI.
4. The commit on GitHub shows a new check for Coveralls with details "First build on function-f at 92.0%", and links to the Job on Coveralls.
5. Line-by-line results indicate the new function is missing coverage.
6. Create a pull request with the new branch.
7. The pull_request check runs and the resulting coverage data triggers a fail status.
8. A detailed comment is posted.