Run results for: concat vs spread vs push

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser: Chrome 131

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

push (spread)

594/s

concat

568/s

push (iterations)

562/s

spread

559/s

View exact numbers

Test name	Executions per second
✓ push (spread)	594 Ops/sec
concat	568 Ops/sec
push (iterations)	562 Ops/sec
spread	559 Ops/sec

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

function generateID(length = 10) {
    const characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    let result = '';
    const charactersLength = characters.length;
    
    for (let i = 0; i < length; i++) {
        // Generate a random index based on characters length
        const randomIndex = Math.floor(Math.random() * charactersLength);
        // Append the character at the random index to the result string
        result += characters[randomIndex];
    }

    return result;
}

function createItem() {
	return { [generateID()]: 'value' };
}

Tests:

concat
let params = new Array(1000).fill('a').map(createItem); let other = new Array(1000).fill('a').map(createItem).concat(params);
spread
let params = new Array(1000).fill('a').map(createItem); let other = [...new Array(1000).fill('a').map(createItem), ...params];
push (spread)
let params = new Array(1000).fill('a').map(createItem); let other = new Array(1000).fill('a').map(createItem); other.push(...params);
push (iterations)
let params = new Array(1000).fill('a').map(createItem); let other = new Array(1000).fill('a').map(createItem); params.forEach(it => other.push(it));