Run results for: Array splice vs object assign

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser: Chrome 119

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Object property assign

37.0M/s

Array splice

2.1M/s

ES6 Object Spread

14K/s

View exact numbers

Script Preparation code:

var input = [];
for (var i = 0; i < 50000; i++) {
    input.push({
        id: i,
        data: 'something'
    })
}

Tests:

Array splice
const index = input.findIndex(val => val.id === 999); input.splice(index, 1, {id: 999, data: 'somethingElse'});
ES6 Object Spread
input = { ...input, [999]: {id: 999, data: 'somethingElse'} }
Object property assign
input[999] = {id: 999, data: 'somethingElse'}