Run results for: map vs findIndex to update unknown array index

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

Benchmark engine: Benchmark.js

map to create new array

47K/s

findIndex to create new array

40K/s

View exact numbers

Test name	Executions per second
✓ map to create new array	47,202 Ops/sec
findIndex to create new array	39,673 Ops/sec

Script Preparation code:

var arr = new Array(15000);
var r = Math.floor(Math.random() * 15000)

arr = arr.map((e, i) => {
  return {
    id: i
  }
})

Tests:

map to create new array
arr.map(e => e && e.id === r ? {...e, targetted: true} : e)
findIndex to create new array
var idx = arr.findIndex(e => e&& e.id === r); arr[idx] = {...arr[idx], targetted: true}