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import { innerJoin } from './innerJoin.js'
const a = {  id: 1,  name: 'a',}const b = {  id: 2,  name: 'b',}const c = {  id: 3,  name: 'c',}const f = innerJoin((r, id) => r.id === id)
test('only returns elements from the first list', () => {  expect(f([a, b, c], [])).toEqual([])  expect(f([a, b, c], [1])).toEqual([a])  expect(f([a, b, c], [1, 2])).toEqual([a, b])  expect(f([a, b, c], [1, 2, 3])).toEqual([a, b, c])  expect(f([a, b, c], [1, 2, 3, 4])).toEqual([a, b, c])})
test('does not remove duplicates', () => {  expect(f([a, a, a], [1, 2, 3])).toEqual([a, a, a])  expect(f([a, b, c], [1, 1, 1])).toEqual([a])})
test('readme example', () => {  const list1 = [1, 2, 3, 4, 5]  const list2 = [4, 5, 6]  const predicate = (x, y) => x >= y  const result = innerJoin(predicate, list1, list2)  expect(result).toEqual([4, 5])})