import lodashStable from 'lodash'; import { LARGE_ARRAY_SIZE } from './utils'; import keyBy from '../src/keyBy'; describe('keyBy', () => { const array = [ { dir: 'left', code: 97 }, { dir: 'right', code: 100 }, ]; it('should transform keys by `iteratee`', () => { const expected = { a: { dir: 'left', code: 97 }, d: { dir: 'right', code: 100 } }; const actual = keyBy(array, (object) => String.fromCharCode(object.code)); expect(actual).toEqual(expected); }); it('should use `_.identity` when `iteratee` is nullish', () => { const array = [4, 6, 6]; const values = [, null, undefined]; const expected = lodashStable.map(values, lodashStable.constant({ 4: 4, 6: 6 })); const actual = lodashStable.map(values, (value, index) => index ? keyBy(array, value) : keyBy(array), ); expect(actual).toEqual(expected); }); it('should work with `_.property` shorthands', () => { const expected = { left: { dir: 'left', code: 97 }, right: { dir: 'right', code: 100 } }; const actual = keyBy(array, 'dir'); expect(actual).toEqual(expected); }); it('should only add values to own, not inherited, properties', () => { const actual = keyBy([6.1, 4.2, 6.3], (n) => Math.floor(n) > 4 ? 'hasOwnProperty' : 'constructor', ); expect(actual.constructor).toEqual(4.2); expect(actual.hasOwnProperty).toEqual(6.3); }); it('should work with a number for `iteratee`', () => { const array = [ [1, 'a'], [2, 'a'], [2, 'b'], ]; expect(keyBy(array, 0)).toEqual({ 1: [1, 'a'], 2: [2, 'b'] }); expect(keyBy(array, 1)).toEqual({ a: [2, 'a'], b: [2, 'b'] }); }); it('should work with an object for `collection`', () => { const actual = keyBy({ a: 6.1, b: 4.2, c: 6.3 }, Math.floor); expect(actual).toEqual({ 4: 4.2, 6: 6.3 }); }); });