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

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; }

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

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Latest run results:

Run details: (Test run date: 24 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36

Browser/OS: Chrome 122 on Windows

Test name	Executions per second
Push item to an array	9798.1 Ops/sec
Append an item by spread	1609.4 Ops/sec
Direct assign an item to an initialized array	10569.1 Ops/sec

Add item to array: push vs spread vs assign: (version: 1)