Run results for: Object.assign vs. JSON String/Parse

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 12_4_5 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.1.2 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 12

Operating system: iOS 12.4.5

Device Platform: Mobile

Date tested: 4 years ago

Test name	Executions per second
Spread operator	4486649.5 Ops/sec
JSON Parse	4484146.5 Ops/sec
Object.assign	4388857.0 Ops/sec

Tests:

Spread operator
var n = {foo: 'bar', hello: [{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'}]}; while(n.length < 1000) { n = [...n]; }
JSON Parse
var n = {foo: 'bar', hello: [{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'}]}; while(n.length < 1000) { n = JSON.parse(JSON.stringify(n)) }
Object.assign
var n = {foo: 'bar', hello: [{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'},{hello: 'world', foo: 'bar'}]}; while(n.length < 1000) { n = Object.assign({}, n); }

Run results for: Object.assign vs. JSON String/Parse

Creating a "new" object reference every time

Spread operator

JSON Parse

Object.assign