Benchmark: JavaScript Object.assign vs for in loop vs for of loop

Tests:

Object.assign
const a = { x: 'xxx', y: 1, z: null } const b = { z: 1, u: 'uuu', v: null } Object.assign(a, b);
for in loop
const a = { x: 'xxx', y: 1, z: null } const b = { z: 1, u: 'uuu', v: null } for (let prop in b) a[prop] = b[prop];
for of loop
const a = { x: 'xxx', y: 1, z: null } const b = { z: 1, u: 'uuu', v: null } for (let [k,v] of Object.entries(b)) a[k] = b[v];

Rendered benchmark preparation results:

Previous results

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36

Browser/OS: Chrome 103 on Mac OS X 10.15.7

JavaScript Object.assign vs for in loop vs for of loop (version: 0)