const {randomHexColorCode} = require('./_30s.js'); test('randomHexColorCode is a Function', () => { expect(randomHexColorCode).toBeInstanceOf(Function); }); test('randomHexColorCode has to proper length', () => { expect(randomHexColorCode().length).toBe(7); }); test('The color code starts with "#"', () => { expect(randomHexColorCode().startsWith('#')).toBeTruthy(); }); test('The color code contains only valid hex-digits', () => { expect( randomHexColorCode() .slice(1) .match(/[^0123456789abcdef]/i) === null ).toBeTruthy(); });