Benchmark: Unique item in Array of objects: reduce vs for loop

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

function getRandomInt(max) {
    return Math.floor(Math.random() * Math.floor(max));
}

var testArr = [];
for (var i = 0; i < 100000; i++) {
    testArr.push({
      val: String(getRandomInt(1000))
    });
}

Tests:

Array Unique
const { resultArray } = testArr.reduce((result, item) => { if(!result.resultMap[item.val]){ result.resultMap[item.val] = true; result.resultArray.push(item) } return result; }, {resultArray: [], resultMap: {}}); return resultArray;
For Loop
const resultArray = []; const resultMap = {}; for(let item of testArr) { if(!resultMap[item.val]){ resultMap[item.val] = true; resultArray.push(item) } } return resultArray;
Array Unique - v2
const resultObj = testArr.reduce((result, item) => { if(!result[item.val]){ result[item.val] = item; } return result; }, {}); const resultArray = Object.values(resultObj); return resultArray;
For Loop - v2
const resultObj = {}; for(let item of testArr) { if(!resultObj[item.val]){ resultObj[item.val] = item; } } const resultArray = Object.values(resultObj); return resultArray;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array Unique
For Loop
Array Unique - v2
For Loop - v2

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Android 11; Mobile; rv:89.0) Gecko/89.0 Firefox/89.0

Browser/OS: Firefox Mobile 89 on Android

View result in a separate tab

Test name	Executions per second
Array Unique	509.2 Ops/sec
For Loop	500.8 Ops/sec
Array Unique - v2	421.2 Ops/sec
For Loop - v2	400.8 Ops/sec

Unique item in Array of objects: reduce vs for loop (version: 2)

Comparing performance of: Array Unique vs For Loop vs Array Unique - v2 vs For Loop - v2

Created: 2 years ago by: Registered User

Jump to the latest result

Array Unique

For Loop

Array Unique - v2

For Loop - v2

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A