Run results for: Object.fromEntries vs reduce for filtering keys

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser: Chrome 120

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Reduce (reuse object)

4K/s

Object.fromEntries

2K/s

Reduce (creating temporary objects)

88/s

View exact numbers

Test name	Executions per second
✓ Reduce (reuse object)	3,947 Ops/sec
Object.fromEntries	2,232 Ops/sec
Reduce (creating temporary objects)	88 Ops/sec

Script Preparation code:

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

Tests:

Object.fromEntries
Object.fromEntries(Object.entries(data).filter((key, value) => value % 2 === 0));
Reduce (reuse object)
Object.entries(data).reduce((acc, [key, value]) => { if (value % 2 === 0) { acc[key] = value; } return acc; }, {});
Reduce (creating temporary objects)
Object.entries(data).reduce((acc, [k, v]) => ({ ...acc, ...(v % 2 === 0 && {[k]: v}) }), {});