Vanilla javascript unit testing

Unit testing is a crucial part of software development that helps ensure individual parts of the code work correctly. For, unit testing can be especially valuable given the dynamic nature of the language.

These are the following approaches:

Using Jest

The Jest is a widely used testing framework developed by Facebook. It is popular for testing React Jest is known for its ease of use, powerful features, and comprehensive documentation.

Syntax:

test('description of the test', () => {
// arrange
// act
// assert
});

Let's consider a simple function that adds two numbers and we will write a unit test for it using Jest.

Function Code:

// math.js
function add(a, b) {
return a + b;
}
module.exports = add;

Test Code:
// math.test.js
const add = require('./math');
test('adds 1 + 2 to equal 3', () => {
expect(add(1, 2)).toBe(3);
});

Running the Tests: To run the tests, you need to the have Jest installed.

We can install it using npm.

npm install --save-dev jest

Then, add a script to your package.json to the run Jest

how to do unit testing in js

javascript unit testing for beginners