typecheck.yml

name: TypeScript Checks

on:
  workflow_call:
  pull_request:
    types: [opened, synchronize]
    branches-ignore: [staging, production]
    paths: ['**.js', '**.ts', '**.tsx', 'package.json', 'package-lock.json', 'tsconfig.json']

jobs:
  typecheck:
    if: ${{ github.actor != 'OSBotify' || github.event_name == 'workflow_call' }}
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - uses: ./.github/actions/composite/setupNode

      - name: Type check with TypeScript
        run: npm run typecheck
        env:
          CI: true

      - name: Check for new JavaScript files
        run: |
          git fetch origin main --no-tags --depth=1

          # Explanation:
          #  - comm is used to get the intersection between two bash arrays
          #    - git diff is used to see the files that were added on this branch
          #    - gh pr view is used to list files touched by this PR. Git diff may give false positives if the branch isn't up-to-date with main
          #  - wc counts the words in the result of the intersection
          count_new_js=$(comm -1 -2 <(git diff --name-only --diff-filter=A origin/main HEAD -- 'src/*.js') <(gh pr view ${{ github.event.pull_request.number }} --json files | jq -r '.files | map(.path) | .[]') | wc -l)
          if [ "$count_new_js" -gt "0" ]; then
            echo "ERROR: Found new JavaScript files in the project; use TypeScript instead."
            exit 1
          fi
        env:
          GITHUB_TOKEN: ${{ github.token }}