Class 12

Installation Steps

Step 1. npm install --save-dev jest

Step 2. Create a JavaScript folder at the root of your project. In this javascript folder create a file called sum

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

Step 3. Create a folder at the root of your project called test and a file inside called registration.test.js

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

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

Step 4. In the package.json add in the following script which contains test of jest:

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

Step 5 Run your test using the following command: npm test