version: 2

shared: &shared
  working_directory: ~/repo
  steps:
    - checkout

    # Download and cache dependencies
    - restore_cache:
        keys:
          - v1-dependencies-{{ checksum "Gemfile.lock" }}
          # fallback to using the latest cache if no exact match is found
          - v1-dependencies-

    - run:
        name: install dependencies
        command: |
          bundle install --jobs=4 --retry=3 --path vendor/bundle

    - save_cache:
        paths:
          - ./vendor/bundle
        key: v1-dependencies-{{ checksum "Gemfile.lock" }}

    # run tests!
    - run:
        name: run tests
        command: bundle exec rake

jobs:
  # RAILS_VERSION=5.1.6
  "ruby-2.4/rails-5.1.6":
    <<: *shared
    docker:
      - image: circleci/ruby:2.4
    environment:
      RAILS_VERSION=5.1.6

  "ruby-2.5/rails-5.1.6":
    <<: *shared
    docker:
      - image: circleci/ruby:2.5
    environment:
      RAILS_VERSION=5.1.6

  "ruby-2.6/rails-5.1.6":
    <<: *shared
    docker:
      - image: circleci/ruby:2.6
    environment:
      RAILS_VERSION=5.1.6

  # RAILS_VERSION=5.2.2
  "ruby-2.4/rails-5.2.2":
    <<: *shared
    docker:
      - image: circleci/ruby:2.4
    environment:
      RAILS_VERSION=5.2.2

  "ruby-2.5/rails-5.2.2":
    <<: *shared
    docker:
      - image: circleci/ruby:2.5
    environment:
      RAILS_VERSION=5.2.2

  "ruby-2.6/rails-5.2.2":
    <<: *shared
    docker:
      - image: circleci/ruby:2.6
    environment:
      RAILS_VERSION=5.2.2

workflows:
  version: 2
  build:
    jobs:
      - "ruby-2.4/rails-5.1.6"
      - "ruby-2.5/rails-5.1.6"
      - "ruby-2.6/rails-5.1.6"
      - "ruby-2.4/rails-5.2.2"
      - "ruby-2.5/rails-5.2.2"
      - "ruby-2.6/rails-5.2.2"