Run results for: lodash flatten vs array.flat

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.1.1 Safari/605.1.15

Browser: Safari 18

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

spread

1.5M/s

lodash flatten

1.3M/s

View exact numbers

Test name	Executions per second
✓ spread	1,515,576 Ops/sec
lodash flatten	1,333,062 Ops/sec

HTML Preparation code:

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

Tests:

spread
const arrayA = ['hi', 'hi', 'hi', 'hi']; const arrayB = ['hi', 'hi', 'hi', 'hi']; const flattened = [ arrayA, arrayB ].flat(); console.log(flattened);
lodash flatten
const arrayA = ['hi', 'hi', 'hi', 'hi']; const arrayB = ['hi', 'hi', 'hi', 'hi']; const flattened = []; const sourceObject = [ arrayA, arrayB ]; sourceObject.forEach((array) => { flattened.push(array) }); _.flatten(flattened); console.log(flattened);