Fix SyntaxError: Unexpected token import

Jest cannot out of the box handle es6 code such as imports

  1. Install babel-jest and dependencies

     npm install --save-dev babel-jest @babel/core @babel/preset-env
  2. Add this to .babelrc:

     "presets": ["@babel/preset-env"]

Fix ReferenceError: regeneratorRuntime is not defined

This is caused by code using async/await

  1. Install @babel/plugin-transform-runtime and @babel/runtime

     npm install --save-dev @babel/plugin-transform-runtime @babel/runtime
  2. Add this to .babelrc:

     "plugins": ["@babel/plugin-transform-runtime"],

Fix Error: connect ECONNREFUSED

Add this to package.json:

  "jest": {
    "testURL": "file://test"