linter.yml

name: ESLint & Prettier
on:
    pull_request:
        branches: [master]
jobs:
    lint:
        name: Lint and format-check changed JS files
        runs-on: ubuntu-latest
        steps:
            - name: Checkout code
              uses: actions/checkout@v4
              with:
                  fetch-depth: 0
                  ref: ${{ github.event.pull_request.head.sha }}

            - name: Set up Node.js
              uses: actions/setup-node@v4
              with:
                  node-version: 20.x
                  cache: "npm"

            - name: Install dependencies
              run: npm ci

            - name: Get changed JavaScript files
              id: get_files
              run: |
                  git diff --diff-filter=ACMRT --name-only ${{ github.event.pull_request.base.sha }}..${{ github.event.pull_request.head.sha }} -- '*.js' '*.mjs' ':!node_modules/**' > changed-js-files.txt
                  if [ -s changed-js-files.txt ]; then
                    echo "has_files=true" >> "$GITHUB_OUTPUT"
                  else
                    echo "has_files=false" >> "$GITHUB_OUTPUT"
                  fi

            - name: Run ESLint on changed files
              if: steps.get_files.outputs.has_files == 'true'
              run: |
                  echo "Linting the following files:"
                  cat changed-js-files.txt
                  xargs -r npx eslint < changed-js-files.txt

            - name: Run Prettier check on changed files
              if: steps.get_files.outputs.has_files == 'true'
              run: |
                  echo "Checking formatting for the following files:"
                  cat changed-js-files.txt
                  xargs -r npx prettier --check < changed-js-files.txt