session-3.md

Testing

Guide: https://jestjs.io/docs/en/getting-started.html

Node setup

• Install nvm: https://github.com/nvm-sh/nvm

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.0/install.sh | bash

# Setup bash profile

nvm ls-remote
nvm install v10  # Node version 10
nvm install v12  # Node version 12
nvm ls

Setup Jest

• Setup: https://jestjs.io/docs/en/getting-started.html

npm init
npm install --save-dev jest

• sum.js

function sum(a, b) {
  return a + b;
}
module.exports = sum;

• sum.test.js

const sum = require('./sum');

test('adds 1 + 2 to equal 3', () => {
  expect(sum(1, 2)).toBe(3);
});

• package.json

{
  "scripts": {
    "test": "jest"
  }
}

npm run test