NodeJS Testing.md

Testing with Mocha and Chai

Mocha - a JavaScript test framework for Node.js programs, featuring browser support, asynchronous testing, test coverage reports, and use of any assertion library.

Chai - BDD (behavior driven development) / TDD (test driven development) assertion library for node and the browser that can be delightfully paired with any javascript testing framework.

Setup

1. Makes sure you have a intialized NodeJS environment.

   $ npm init
   

2. Install testing dependencies

   $ npm install mocha chai --save-dev
   

3. Create a directory to house your test. Below is an example of testing an application

   root/
   ├─── app/
   │   └── app.js
   ├─── test/
   │   ├── appTest.js
   └── index.js
   

Example Test Snippet

// app.js
module.exports = function () {
    return 'hello';
}

// appTest.js
const assert = require('chai').assert;
const app = require('../app')

describe('App', function () {
    it('app should return hello', function () {
        assert.equal(app(), 'hello');
    });

    it('should return type string', function () {
        assert.typeOf(app(), 'string');
    })
});