on: push
jobs:
  ok1:
    services: ${{ fromJSON('{}') }}
    runs-on: ubuntu-latest
    steps:
      - run: echo
  err1:
    services: redis
    runs-on: ubuntu-latest
    steps:
      - run: echo
  err2:
    services: ${{ 'redis' }}
    runs-on: ubuntu-latest
    steps:
      - run: echo
