Benchmark: Add item to array: push vs spread vs assign vs assign+grow

Script Preparation code:

window.MAX_SIZE = 1000;

Tests:

Push item to an array
const items = []; for (let i = 0; i < MAX_SIZE; i++) { items.push(i); }
Append an item by spread
let items = []; for (let i = 0; i < MAX_SIZE; i++) { items = [...items, i]; }
Direct assign an item to an initialized array
const items = new Array(MAX_SIZE); for (let i = 0; i < MAX_SIZE; i++) { items[i] = i; }
Direct assign an item to an empty array
const items = new Array(); for (let i = 0; i < MAX_SIZE; i++) { items[i] = i; }

Rendered benchmark preparation results:

Previous results

Test case name	Result
Push item to an array
Append an item by spread
Direct assign an item to an initialized array
Direct assign an item to an empty array

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Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Mac OS X 10.15.7

Test name	Executions per second
Push item to an array	9688.7 Ops/sec
Append an item by spread	1198.9 Ops/sec
Direct assign an item to an initialized array	10073.2 Ops/sec
Direct assign an item to an empty array	9743.5 Ops/sec

Add item to array: push vs spread vs assign vs assign+grow (version: 0)