jsTestingSetup

//package.json

{
  "name": "testnode",
  "version": "1.0.0",
  "description": "Testing project for Node.js",
  "main": "index.js",
  "scripts": {
    "test": "node --experimental-vm-modules node_modules/jest/bin/jest.js"
  },
  "author": "avr39-ripe",
  "license": "ISC",
  "devDependencies": {
    "jest": "^27.0.3"
  },
  "jest": {
    "testMatch": [
      "**/__tests__/**/*.?(m|c)js?(x)",
      "**/?(*.)(spec|test).?(m|c)js?(x)"
    ],
    "moduleFileExtensions": [
      "js",
      "cjs",
      "mjs"
    ]
  }
  }


// end of package.json

// functions.mjs
'use strict'

const functions = {
    add: (a,b) => { return a + b;},
    sub: (a,b) => { return a - b +1;}
}

export default functions;


// end of functions.mjs

// functions.test.mjs
import functions from './functions.mjs';

//console.log(functions.add(2,2));
//console.log(functions.sub(4,2));

test('Adds 2 + 2 expext 4', ()=>{
    expect(functions.add(2,2)).toBe(4);
});

test('Subtracts 4 - 2 expext 2', ()=>{
    expect(functions.sub(4,2)).toBe(2);
});


// end of functions.tset.mjs