Unit Testing

Unit tests verify individual functions or components in isolation.

Syntax

NODEJS

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const assert = require('assert');

function add(a, b) { return a + b; }

assert.strictEqual(add(1, 2), 3);
assert.strictEqual(add(-1, 1), 0);

Unit Testing with Jest

NODE

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// math.js
function add(a, b) { return a + b; }
function divide(a, b) {
    if (b === 0) throw new Error("Cannot divide by zero");
    return a / b;
}

// math.test.js
// describe("Math", () => {
//     test("add", () => {
//         expect(add(2, 3)).toBe(5);
//     });
//     test("divide", () => {
//         expect(divide(10, 2)).toBe(5);
//     });
//     test("divide by zero", () => {
//         expect(() => divide(1, 0)).toThrow();
//     });
// });

Try It Yourself

Next Lesson

Debugging with Node