Run results for: Object.assign vs direct assignment multiple properties

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36

Browser: Chrome 125

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Direct Assignment	42.5 Ops/sec
Object.assign	156.4 Ops/sec

Script Preparation code:

var data = {};

Tests:

Direct Assignment
for(var i = 0; i < 10000; i++) { data[`prop_${i}`] = true; data[`prop_${i}1`] = true; data[`prop_${i}2`] = true; data[`prop_${i}3`] = true; data[`prop_${i}4`] = true; data[`prop_${i}5`] = true; data[`prop_${i}6`] = true; data[`prop_${i}7`] = true; data[`prop_${i}8`] = true; data[`prop_${i}9`] = true; data[`prop_${i}10`] = true; data[`prop_${i}11`] = true; data[`prop_${i}12`] = true; }
Object.assign
for(var i = 0; i < 10000; i++) { var propName = `prop_${i}`; Object.assign(data, { [propName]: true }); }