Benchmark: _.uniqueBy vs Set vs Map

HTML Preparation code:

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

Script Preparation code:

var MyArr = Array.from(
  {
    length: 40,
  },
  () => {
    return {
      a: Math.floor(Math.random() * 40),
    };
  }
);

var myCopy = null;

Tests:

uniqBy
myCopy = _.uniqBy(MyArr, (obj) => obj.a);
Set
const seen = new Set(); myCopy = MyArr.filter(item => { if (seen.has(item.a)) { return false; } seen.add(item.a); return true; });
Map
const seen = new Map(); myCopy = MyArr.filter(item => { if (seen.has(item.a)) { return false; } seen.set(item.a, true); return true; });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
uniqBy
Set
Map

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 11 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36

Browser/OS: Chrome 139 on Mac OS X 10.15.7

View result in a separate tab

uniqBy

1.8M/s

Set

1.6M/s

Map

1.6M/s

View exact numbers

Test name	Executions per second
✓ uniqBy	1,827,759 Ops/sec
Set	1,621,590 Ops/sec
Map	1,551,428 Ops/sec

_.uniqueBy vs Set vs Map (version: 3)

Comparing performance of: `uniqBy vs Set vs Map`

Created: 11 months ago by: Registered User

Go to the latest result

uniqBy

Set

Map

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

_.uniqueBy vs Set vs Map (version: 3)

Comparing performance of: uniqBy vs Set vs Map

Created: 11 months ago by: Registered User

Go to the latest result

uniqBy

Set

Map

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Related benchmarks

Comparing performance of: `uniqBy vs Set vs Map`