Run results for: merge vs set a value

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.88 Safari/537.36

Browser: Chrome 79

Operating system: Windows

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
merge	23124582.0 Ops/sec
set a value	918300160.0 Ops/sec

Tests:

let obj1 = { first: 'first', second: 'second', third: 'third' };
const obj2 = { fourth: 'fourth' };

obj1 = {
  ...obj1,
  ...obj2,
};

​x
 
let obj1 = { first: 'first', second: 'second', third: 'third' };const obj2 = { fourth: 'fourth' };​obj1 = {  ...obj1,  ...obj2,};

let obj1 = { first: 'first', second: 'second', third: 'third' };

obj1.fourth = 'fourth';

 
let obj1 = { first: 'first', second: 'second', third: 'third' };​obj1.fourth = 'fourth';