const expect = require('expect'); const sortedLastIndex = require('./sortedLastIndex.js'); test('sortedLastIndex is a Function', () => { expect(sortedLastIndex).toBeInstanceOf(Function); }); test('Returns the highest index to insert the element without messing up the list order', () => { expect(sortedLastIndex([10, 20, 30, 30, 40], 30)).toBe(4); });