const { byteSize } = require('./_30s.js'); const Blob = class { constructor(s) { return { size: Buffer.byteLength(s.toString()) }; } }; test('byteSize is a Function', () => { expect(byteSize).toBeInstanceOf(Function); }); test('Works for a single letter', () => { expect(byteSize('a')).toBe(1); }); test('Works for a common string', () => { expect(byteSize('Hello World')).toBe(11); }); test('Works for emoji', () => { expect(byteSize('😀')).toBe(4); });