Run results for: spread large array (100 elements) performance (vs slice, splice, concat, for)

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.5060.114 Safari/537.36 Edg/103.0.1264.51

Browser: Chrome 103

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Splice	5798981.0 Ops/sec
Slice	6528454.0 Ops/sec
Concat	6396047.5 Ops/sec
Spread	6200411.5 Ops/sec
For cycle with preallocation	3354135.2 Ops/sec

Script Preparation code:

testArray = [];
for (let i = 0; i < 100; i++) testArray.push(i)

Tests:

Splice
const newTestArray = testArray.splice(0);
Slice
const newTestArray = testArray.slice();
Concat
const newTestArray = testArray.concat();
Spread
const newTestArray = [...testArray];
For cycle with preallocation
const testArrLen = testArray.length; const resArr = new Array(testArrLen); for (let i = 0; i < testArrLen; i++) { resArr[i] = testArray[i]; }

Run results for: spread large array (100 elements) performance (vs slice, splice, concat, for)

Splice

Slice

Concat

Spread

For cycle with preallocation