Please go through the demo to create a javascript workspace.

Step1: Create directory

$ mkdir js-workspace

Step2: Step into the directory and initialize a repository. Then copy .gitignore file to that directory

The .gitignore file content can be found at https://github.com/github/gitignore/blob/master/Node.gitignore

$ git init

Step3: Create a node-js workspace by creating a package.json file.

$ npm init

Step4: Add dependencies for your project. Currently, we depend on JEST, which is a unit test framework.

$ npm install jest --save-dev

Step5: create a folder to hold all the test.

$ mkdir __tests__

Step6: Create a unit-test file under the __tests__ folder, and a source code file under the root folder.

$ touch main.js ## if you use PowerShell please type: New-Item main.js -Type File
$ cd __tests__
$ touch main-spec.js

Step7: Write a test first

const add = require('../main');

it ('should add two numbers', () => {
    expect(add(2, 3)).toBe(5);
});

Step8: run the test from the command line:

## Suppose that we are in the root folder
$ node_modules/.bin/jest

Step9: Oh my! the test failed. Let's fix it in main.js file

function add (left, right) {
    return left + right;
}

module.exports = add;

Step10: Run the test again.

Please do it again all by yourselfs in 10 minutes.