Github actionscan write errors and warning directly in their output, which result into annotations into the Github checks. It can even provide a filename, line & col number, allowing to display the annnotations inside the PR diff directly, at the right place.

More advanced usage of annotations can be made using theAPI, but regarding the linters provided in Symfony components, it seems the shortcut using output is a great way to enhance the integration with Github Actions.

This PR starts by proposing these changes in the yaml linter:

• add thegithub format, which is the same as thetxt one, except for errors and warning, for which we'll adapt the output to the Github annotations format.
• remove thetxt format as default, and autodetect if the script is running in a Github action context, then usegithub format. If it's not, we fallback totxt as before.

Once we agree on the details, we could perform the same for other linters (xliff, twig, ...)

Here is a PR using it:ogizanagi/symfony-lint-gha-demo#2

and some screenshots:

PR checks run	PR checks annotations	PR diff

(tests to add)

This was inspired byPHPStan which is already auto-adapting the output according to the CI, usinghttps://github.com/OndraM/ci-detector