Development

Create a new local branch for any development, for example git checkout -b featureA
Update the source code in index.js
Build dist file(s) using npm run build
Commit any changed files, note the SHA of the commit
Push the local branch to GitHub
In a test repository, create a test branch, change the action to point at the new commit. Example

name: End-to-end tests
on: [push]
jobs:
  cypress-run:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v1
      # use specific commit pushed to GitHub
      - uses: cypress-io/github-action@2a1baeb

You can use cypress-gh-action-example or cypress-gh-action-monorepo as test projects.

Push the change and make sure the new feature performs correctly. If yes, open a pull request.

For pull request reviewers:

When merging a pull request, squash all commits into one.
Make sure the commit subject and body follow semantic commit convention. I prefer simplicity:

feat: added new parameter
fix: fixed a bug

If you need to bump major version, mark it as breaking change in the body of the commit's message like:

fix: upgrade dependency X

BREAKING CHANGE: requires Node 8 to run

New versions of this action will be released automatically by the CI, see .github/workflows/main.yml. This will create a new GitHub release and will update the current /v1 branch. Thus every user that use - uses: cypress-io/github-action@v1 will be using the new version automatically.