Run results for: `Array.slice(0, N)` vs `Array.length = N`

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36

Browser: Chrome 136

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

`Array.slice(0, N)`

44.8M/s

`Array.length = N`

36.2M/s

`Object.assign([], arr)` with `Array.length = N`

680K/s

View exact numbers

Test name	Executions per second
✓ `Array.slice(0, N)`	44,807,736 Ops/sec
`Array.length = N`	36,174,528 Ops/sec
`Object.assign([], arr)` with `Array.length = N`	679,703 Ops/sec

Script Preparation code:

var arr = Array.from(Array(100).keys());

Tests:

`Array.slice(0, N)`
arr.slice(0, 20);
`Array.length = N`
arr.length = 20;
`Object.assign([], arr)` with `Array.length = N`
var newArr = Object.assign([], arr); newArr.length = 20;