How to setup Node.js testing with ava

This tutorial will explain from the project setup. To skip the setup you can go to installation

Create new node.js project

$ npm init --y

Create a simple function to test

// add.js
/**
 * Add two numbers
 * @param {number} a a number
 * @param {number} b a number
 * @returns a + b
 */
exports.add = (a, b) => a + b;

You can test that function with console.log

Install ava to the project

$ npm i -D ava

Add test script that runs the ava binary

// package.json
{
  // ...
  "scripts": {
    // ...
    "test": "ava"
  }
}

Create a test file to test the add function

// add.test.js
const test = require('ava');
const { add } = require('./add');

test('should correctly add 1 and 1', t => {
  t.is(add(1, 1), 2);
});

Then you can run the test script

$ npm test

To get types/intellisense in vscode, modify how to import ava

- const test = require("ava");
+ const { default: test } = require("ava");