Run results for: Reduce vs Flatmap 10000 items

Run details:

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Mobile Safari/537.36

Browser: Chrome Mobile 126

Operating system: Android

Device Platform: Mobile

Date tested: 2 years ago

Benchmark engine: Benchmark.js

Flatmap

168/s

Reduce

0/s

View exact numbers

Test name	Executions per second
✓ Flatmap	168 Ops/sec
Reduce	0 Ops/sec

Script Preparation code:

let id = 0

function generateId() {
    id = id + 1
    return id
}

function generateOject(id) {
    changes = []
    for (let i = 0; i < 10; i++) {
        changes.push({
            id,
            oldValue: i * 10,
            newValue: i * 20
        })
    }
    return {
        id,
        name: `Object#${id}`,
        changes
    }
}

window.lookup = {};

for (let i = 0; i < 10000 ; i++) {
    window.lookup[generateId()] = generateOject();
}

Tests:

Reduce
const uniqNodes = new Set(); const changes = Object.values(window.lookup).reduce((changes, node) => { if (!uniqNodes.has(node)) { uniqNodes.add(node); return changes.concat(node.changes) } return changes }, []);
Flatmap
const uniqNodes = new Set(); Object.entries(window.lookup).forEach(([_identifier, node]) => { if (!uniqNodes.has(node)) { uniqNodes.add(node); } }); const changes = Array.from(uniqNodes).flatMap(node => node.changes)