language: node_js
node_js:
  - "6"
before_install:
  - npm install -g yarn
install:
  - yarn
script:
  - yarn run test
cache:
  directories:
    - $HOME/.yarn-cache

language: node_js
node_js:
  - "4"
  - "6"
  - "node"
before_install:
  - npm install -g yarn
install:
  - yarn
script:
  - yarn run test
cache:
  directories:
    - $HOME/.yarn-cache

Add Node.js v4 and latest to Travis config
Add Node.js v4 and latest to Travis config
