Software Testing Using Node.js

Software testing is very important – without it, bugs sneak into the wild where they’re more difficult and expensive to fix. Automating testing can significantly increase test coverage and also reduce long-term costs. During this blog post, we’ll see how we will perform testing using Node.js as JavaScript is a widely used language in today’s world.

Which Framework Should I Use to Test my Node.js Application?

There are various frameworks available for testing a Node.Js application, each having its advantages and disadvantages. Here is the list:

1. Mocha

Mocha is a test framework of Javascript for Node.js programs. It is highly used for asynchronous testing. It’s a superb framework that permits asynchronous/await with TypeScript or Babel. It is designed with the mindset to test both synchronous and asynchronous code. It is a feature-rich JavaScript test framework running on Node.js and within the browser. It provides a set of functions that execute in particular order & logs the result on the terminal. Mocha features a CLI that we mention below and is filled with helpful features. Mocha is one of the foremost popular NodeJS testing frameworks.

Installation:

npm install mocha -g# project install
npm install mocha --save-dev

2. Chai

Chai is a commonly used JavaScript testing framework to write Unit tests. It allows you to use natural language constructs when developing your tests.

Installation:

npm install --save-dev chai

3. Mockery

Mockery gives you an easy-to-use API with which you’ll hook in your mocks without having to get your hands dirty with the specified cache or other Node implementation details. Mockery isn’t a mocking framework. It allows you to work more easily together with your framework of choice (or no framework) to hook your mocks into all the proper places within the code you would like to check.

Installation:

npm install mockery

How to use Mocha for testing:

1. Install Mocha using the above code.
2. Create a root directory for the example app.
3. Create a test file example.app.js under the root directory.
4. Paste the below code snippet:

//import assert
const assert = require('assert'); 
describe('My First Test', () => { 
   it('should return 4', () => { 
      assert.equal(2 + 2, 4); }); 
   it('should return 16', () => { 
      assert.equal(4 * 4, 16); 
   }); 
});

Here is the meaning of several terms used in the above code:

1. describe — collection or bundle of tests. Here, its name is “My First Test”
2. it — a single test, “it.. should return x”
3. assert — how you validate your test works or fails, “assert.equal(2+ 2, 4)”

Update package.json

• open package.json
• change your test mode to “mocha” in the script using the below code.

"scripts": {"test": "mocha"}

Save all the changes & run it.

Run test:

npm run test

All test should pass 😊

How to use Chai for testing:

1. Install chai
2. Create a root directory for the example app.
3. Create a test file example.app.js under the root directory.
4. Paste the below code snippet

//import chai
const expect = require('chai').expect; 
describe('My First Test', () => {
   it('should return 4', () => { 
      expect(2 + 2).to.equal(4); }); 
   it('should return 16', () => { 
      expect(4 * 4).to.equal(16); 
   }); 
});

Save all the changes & run it.

Run test:

npm run test

All test should pass ✅

I hope this article helped you understand the basic overview of Software Testing using Node.js. Thanks for reading 🤓