Run results for: Object.fromEntries vs reduce vs for loop

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:150.0) Gecko/20100101 Firefox/150.0

Browser: Firefox 150

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 2 months ago

For loop

30K/s

Object.fromEntries

12K/s

Reduce (creating temporary objects)

1/s

View exact numbers

Test name	Executions per second
✓ For loop	29,871 Ops/sec
Object.fromEntries	11,801 Ops/sec
Reduce (creating temporary objects)	1 Ops/sec

Script Preparation code:

var data = Array.from(Array(10000).keys());

Tests:

Object.fromEntries
Object.fromEntries(data.map((key) => [key, 'x']));
Reduce (creating temporary objects)
data.reduce((acc, k) => ({ ...acc, [k]: 'x' }), {});
For loop
const obj = {}; for (const d of data) { obj[d] = 'x'; }