In my second rotation, I used to help to create test coverage workflow to accommodate both Jest and Vitest two frameworks.

As nyc package only aworks with Jest well. For Vitest, it needs some special configuration.In vitest.config.ts, add below section For Jest, configure output directory to be .nyc_output.

    coverage: {
        provider: 'Istanbul',
        reporter: ['json', 'json-summary']
    }

So in the repo, you will either use jest --coverage --coverageReporters=json or vitest --coverage as your npm run test command in package.json.

Then in the behind scene github action workflow, how do we accmmodate these two frameworks?

For Jest, command will be run as below

    # below command all run in package.json located folder
    nyc --all jest --coverage --coverageReporters=json
    nyc merge .nyc_output raw-coverage.json
    nyc report --reporter=json-summary --report-dir=coverage

For Vitest, just run the command, then it is fine.

For airflow test coverage, we use python coverage.py to accompolish the goal, several key things to note:

1. Report generates in XML format, then we convert to json format by custom code if needed
2. Airflow test should not be running locally, instead it should run in cloud(GCP composer)