Setting up Babel and nodemon

Inital set-up

Set up project:

mkdir project
cd project
npm init -y

Install dev dependencies:

npm i --save-dev babel-cli babel-preset-latest nodemon

Configure Babel by adding the lines below to package.json:

"babel": {
  "presets": [
    "latest"
  ]
},

Scripts

Add some convenience scripts to package.json:

"scripts": {
  "babel-node": "babel-node --presets=latest",
  "start": "nodemon --exec npm run babel-node -- ./index.js",
  "build": "babel src -d dist"
},

To start the Node.js REPL:

npm run babel-node

To start the app in development mode (letting Babel interpret ES6 code):

npm start

To build the ES5 code in the build directory from the ES6 code in the src directory:

npm build

Adding in Mocha and chai

npm install --save-dev mocha chai

Add this line to the scripts section in package.json:

"scripts": {
  ...
  "mocha": "mocha --compilers js:babel-register",
  "test": "mocha --compilers js:babel-register --recursive ./test/"
}

Create a new directory called test:

mkdir test

Minimal test (to save e.g. as test/test.js):

'use strict'

import { expect } from 'chai'

describe('test', function () {
  it('should pass', function () {
    expect('string').to.be.a('string')
  })
})