Benchmark: Array.slice vs Array.concat vs Spread operator

Script Preparation code:

window.testArray = [1, 'a', undefined, null, false, { a: 123 }, [1, 2, 3]];
window.arraySlice = Array.prototype.slice;
window.arrayConcat = Array.prototype.concat;

Tests:

Array.prototype.slice [direct call]
const a = window.testArray.slice();
Array.prototype.slice [saved function call]
const a = arraySlice.call(window.testArray);
Array.prototype.concat [direct call]
const a = window.testArray.concat([]);
Array.prototype.concat [saved function call]
const a = window.arrayConcat.call(window.testArray, []);
Spread operator
const a = [...window.testArray];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.slice [direct call]
Array.prototype.slice [saved function call]
Array.prototype.concat [direct call]
Array.prototype.concat [saved function call]
Spread operator

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: one month ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.prototype.slice [direct call]	5267453.0 Ops/sec
Array.prototype.slice [saved function call]	2595663.0 Ops/sec
Array.prototype.concat [direct call]	2924552.0 Ops/sec
Array.prototype.concat [saved function call]	1874404.0 Ops/sec
Spread operator	5111024.0 Ops/sec

Array.slice vs Array.concat vs Spread operator (version: 2)

Comparing performance of: Array.prototype.slice [direct call] vs Array.prototype.slice [saved function call] vs Array.prototype.concat [direct call] vs Array.prototype.concat [saved function call] vs Spread operator

Created: 4 years ago by: Registered User

Jump to the latest result

Array.prototype.slice [direct call]

Array.prototype.slice [saved function call]

Array.prototype.concat [direct call]

Array.prototype.concat [saved function call]

Spread operator

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A