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import { nextIndex } from './nextIndex.js'
const list = [ 1, 2, 3, 4 ]
test('happy path', () => {  expect(nextIndex(2, list)).toBe(3)})
test('go back to the start', () => {  expect(nextIndex(3, list)).toBe(0)})
test('current index is too big', () => {  expect(nextIndex(32, list)).toBe(0)})