Jest

Getting Started

1. Install

   npm install --save-dev jest

2. Build test

   sum.js

   export function sum(a, b) {
     return a + b;
   }
   sum.test.js

   import { sum } from "./sum.js";
   
   test("adds 1 + 2 to equal 3", () => {
     expect(sum(1, 2)).toBe(3);
   });

3. Add Script

   package.json

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

References

• Offical Docs
• Usage API