Run results for: Object arrays: findIndex vs for loop for finding and editing an array item.

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 17_5_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.5 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 17

Operating system: iOS 17.5.1

Device Platform: Mobile

Date tested: 2 years ago

Benchmark engine: Benchmark.js

for loop

28K/s

findIndex

21K/s

View exact numbers

Test name	Executions per second
✓ for loop	28,253 Ops/sec
findIndex	21,236 Ops/sec

Script Preparation code:

/* make a new array with 15k items */
var arr = new Array(15000);

/* fill array tems with basic object */
arr.fill({ id: 0 });

/* generate 2 random numbers in our 15k range */
var foo = Math.floor(Math.random() * 15000);
var bar = Math.floor(Math.random() * 15000);

/* set the index of arr[foo] to foo for our tests */
arr[foo].id = foo;

Tests:

findIndex
const bookFreePlatform = (arr, foo, bar) => { /* find array index where id == foo */ var index = arr.findIndex(item => item.id === foo); /* findIndex returns -1 on fail, so test for that */ if ( index != -1 ) { /* ok, we have an index, lets edit that entry, and console log it for fun */ arr[index].id = bar; console.log(arr[index]); } /* return altered array */ return arr; } bookFreePlatform(arr, foo, bar);
for loop
const bookFreePlatform = (arr, foo, bar) => { /* find array item where id == foo */ for (let i = 0; i < arr.length; i++) { /* not an error check, just a simple comparison */ if (arr[i].id === foo) { /* if we got here, it found and index, lets edit it and log it again */ arr[i].id = bar; console.log(arr[i]); /* stop the loop to save time and resources, we're done */ break; } } /* return altered array */ return arr; } bookFreePlatform(arr, foo, bar);

Run results for: Object arrays: findIndex vs for loop for finding and editing an array item.

Test finding an object array via findIndex or by using a for loop, and edit the value of that index.

findIndex

for loop