- Jest is a wonderful testing library created by Facebook to help test JavaScript code, React components, and much more.
- Jest is it not only has a similar syntax to other testing/assertion libraries like Jasmine and Chai, but with Jest your tests run in parallel so they are executed much faster than other testing frameworks.
mkdir learn-jest
cd learn-jest
npm init -y
mkdir src
mkdir __tests__
touch src/index.js
touch __tests__/first.test.js
npm i -D typescript
npx tsc --init
npm i -D jest ts-jest @types/jest
npx ts-jest config:init