Run results for: Array concat vs spread vs push spread, loop, apply

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 16_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/108.0.5359.112 Mobile/15E148 Safari/604.1

Browser: Chrome Mobile iOS 108

Operating system: iOS 16.1

Device Platform: Mobile

Date tested: one year ago

Test name	Executions per second
Array.prototype.concat	3253352.0 Ops/sec
spread operator	3115354.0 Ops/sec
Push Spread	2030539.0 Ops/sec
Push Apply	2324264.0 Ops/sec
Push Loop	3230400.0 Ops/sec

Script Preparation code:

var subarrs = [
 [ "hello", true, 7 ],
 [ "yes", "no", "maybe", false, 27 ],
 [ 16, "I", "wonder", "what", "will", "be", "fastest"]
];

Tests:

Array.prototype.concat
var other = [ 1, 2, 3 ] for (var len = subarrs.length, i = 0; i < len; i++){ other = other.concat(subarrs[i]); } return other;
spread operator
var other = [ 1, 2, 3 ] for (var len = subarrs.length, i = 0; i < len; i++){ other = [ ...other, ...subarrs[i] ] } return other;
Push Spread
var other = [ 1, 2, 3 ] for (var len = subarrs.length, i = 0; i < len; i++){ other.push(...subarrs[i]); } return other;
Push Apply
var other = [ 1, 2, 3 ] for (var len = subarrs.length, i = 0; i < len; i++){ other.push.apply(other, subarrs[i]); } return other;
Push Loop
var other = [ 1, 2, 3 ] for (var len = subarrs.length, i = 0; i < len; i++){ for (var jarr = subarrs[i], jen = jarr.length, j = 0; j < jen; j++){ other.push(jarr[j]); } } return other;

Run results for: Array concat vs spread vs push spread, loop, apply

Compare the new ES6 spread operator with the traditional concat() method and push

Array.prototype.concat

spread operator

Push Spread

Push Apply

Push Loop