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

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36 OPR/94.0.0.0 (Edition Yx 05)

Browser: Opera 94

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Array.prototype.concat	1284985.0 Ops/sec
spread operator	2089750.0 Ops/sec
Push Spread	2508434.0 Ops/sec
Push Apply	2534271.0 Ops/sec
Push Loop	3056483.0 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