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 127.0.0.1:80

Add this to package.json:

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