Running Mocha 6 ES6 tests with Babel 7, how to set up?

Look at the project documentation:

npm install --save-dev babel-register

In your package.json file make the following changes:

{
  "scripts": {
    "test": "mocha --require babel-register"
  }
}

Some features will require a polyfill:

npm install --save-dev babel-polyfill

{
  "scripts": {
    "test": "mocha --require babel-polyfill --require babel-register"
  }
}

Testing in ES6 with Mocha and Babel 7. Look here: https://dev.to/bnorbertjs/my-nodejs-setup-mocha--chai-babel7-es6-43ei or http://jamesknelson.com/testing-in-es6-with-mocha-and-babel-6/

npm install --save @babel/runtime 
npm install --save-dev @babel/plugin-transform-runtime

And, in .babelrc, add:

{
    "presets": ["@babel/preset-env"],
    "plugins": [
        ["@babel/transform-runtime"]
    ]
}