Benchmark: compare content of two objects using Object.entries VS for...in

Script Preparation code:

function makeid() {
    var text = "";
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

    for (var i = 0; i < 5; i++)
        text += possible.charAt(Math.floor(Math.random() * possible.length));

    return text;
}

window.parentObj = {};

const samples = 1000;

const a = {};

for (let i = 0; i < samples; i++) {
    a[makeid()] = makeid();
}

const b = JSON.parse(JSON.stringify(a));

const c = {};

for (let i = 0; i < samples; i++) {
    c[makeid()] = makeid();
}

window.parentObj = {a: a, b: b, c: c};

Tests:

Object.entries
const a = window.parentObj.a; const b = window.parentObj.b; const entries = Object.entries(a); const isNotEqual = entries.some(([k, v], i) => b[k] != v); if (isNotEqual) return false; return entries.length === Object.keys(b).length;
Object for..in
const a = window.parentObj.a; const b = window.parentObj.b; for(var key in a) { if (a[key] != b[key]) return false; }; return Object.keys(a).length === Object.keys(b).length;
Object for..in #2
const a = window.parentObj.a; const b = window.parentObj.b; let lengthA = 0; for(var key in a) { lengthA = lengthA + 1; if (a[key] != b[key]) return false; }; return lengthA === Object.keys(b).length;
Object for..in #3
const a = window.parentObj.a; const b = window.parentObj.b; let lengthA = 0; for(var key in a) { lengthA = lengthA + 1; if (a[key] != b[key]) return false; }; let lengthB = 0; for(var key in b) { lengthB = lengthB + 1; }; return lengthA === lengthB;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.entries
Object for..in
Object for..in #2
Object for..in #3

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36

Browser/OS: Chrome 79 on Windows

View result in a separate tab

Test name	Executions per second
Object.entries	2186.4 Ops/sec
Object for..in	4334.8 Ops/sec
Object for..in #2	5610.7 Ops/sec
Object for..in #3	4936.2 Ops/sec

compare content of two objects using Object.entries VS for...in (version: 1)

Comparing performance of: Object.entries vs Object for..in vs Object for..in #2 vs Object for..in #3

Created: 3 years ago by: Registered User

Jump to the latest result

Object.entries

Object for..in

Object for..in #2

Object for..in #3

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A