Run results for: Native uniqueBy vs Lodash _.uniqBy

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36

Browser: Chrome 134

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

Lodash uniqBy

10.4M/s

Native uniqueBy

9.9M/s

View exact numbers

Test name	Executions per second
✓ Lodash uniqBy	10,358,056 Ops/sec
Native uniqueBy	9,931,331 Ops/sec

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var users = [
  { 'user': 'joey',  'age': 29 },
  { 'user': 'joey',  'age': 32 },
  { 'user': 'ross',    'age': 41 },
  { 'user': 'ross',    'age': 25 },
  { 'user': 'ross',    'age': 48 },
  { 'user': 'chandler', 'age': 39 },
  { 'user': 'chandler', 'age': 12 },
  { 'user': 'chandler', 'age': 41 }
]

Tests:

Native uniqueBy
const uniqueBy = (array, key) => [...new Map(array.map(item => [item[key], item])).values()]; let uniqued = uniqueBy(users, 'user');
Lodash uniqBy
let uniqued = _.uniqBy(users, ['user']);