Benchmark: Array.prototype.concat vs spread operator (large, small diff

Script Preparation code:

// preparation
var a = Array.from({length: 1000}).map((_, i)=>`${i}`);
var b = Array.from({length: 2000}).map((_, i)=>`${i}`);
var aSmall = ['a', 'b', 'c', 'd'];
var bSmall = ['e', 'f', 'g', 'h', 'i'];

Tests:

Array.prototype.concat small
aSmall.concat(bSmall);
spread operator (small)
[...aSmall, ...bSmall]
Array.prototype.concat (large)
a.concat(b);
spread operator (large)
[...a, ...b]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.concat small
spread operator (small)
Array.prototype.concat (large)
spread operator (large)

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 16_7_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.6 Mobile/15E148 Safari/604.1

Browser/OS: Mobile Safari 16 on iOS 16.7.1

View result in a separate tab

Test name	Executions per second
Array.prototype.concat small	8408833.0 Ops/sec
spread operator (small)	6739389.0 Ops/sec
Array.prototype.concat (large)	460664.9 Ops/sec
spread operator (large)	125163.0 Ops/sec

Array.prototype.concat vs spread operator (large, small diff (version: 0)

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

Comparing performance of: Array.prototype.concat small vs spread operator (small) vs Array.prototype.concat (large) vs spread operator (large)

Created: one year ago by: Guest

Jump to the latest result

Array.prototype.concat small

spread operator (small)

Array.prototype.concat (large)

spread operator (large)

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A