Run results for: Array.prototype.concat vs spread operator - with Arrays of Objects (Updated Oct 2020)

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.121 Safari/537.36

Browser: Chrome 85

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
Array.prototype.concat	4828677.0 Ops/sec
spread operator (spread at head)	12422260.0 Ops/sec
spread operator (spread at tail)	13240250.0 Ops/sec

Tests:

Array.prototype.concat
var params = [ { 'ten': 10 }, { 'six': 6 }, {'nested': { 'five': 5 }} ]; var other = [ { 'one': 1 }, { 'two': 2 } ].concat(params);
spread operator (spread at head)
var params = [ { 'ten': 10 }, { 'six': 6 }, {'nested': { 'five': 5 }} ]; var other = [ ...params, { 'one': 1 }, { 'two': 2 } ];
spread operator (spread at tail)
var params = [ { 'ten': 10 }, { 'six': 6 }, {'nested': { 'five': 5 }} ]; var other = [ { 'one': 1 }, { 'two': 2 }, ...params ];