Run results for: Object look-up

Run details:

User agent: Mozilla/5.0 (X11; CrOS x86_64 14541.0.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36

Browser: Chrome 126

Operating system: Chrome OS 14541.0.0

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

in with prototype

3.2M/s

access property with prototype

3.2M/s

in without prototype

2.7M/s

access property without prototype

2.7M/s

hasOwnProperty without prototype

637K/s

hasOwnProperty with prototype

595K/s

View exact numbers

Test name	Executions per second
✓ in with prototype	3,225,178 Ops/sec
access property with prototype	3,197,786 Ops/sec
in without prototype	2,682,230 Ops/sec
access property without prototype	2,659,142 Ops/sec
hasOwnProperty without prototype	636,502 Ops/sec
hasOwnProperty with prototype	595,494 Ops/sec

Script Preparation code:

var withPrototype = {};
var withoutPrototype = Object.create(null);

for (var i=0; i<100; ++i) {
  withPrototype[i] = true;
  withoutPrototype[i] = true;
}

var hasOwnProperty = Object.prototype.hasOwnProperty;

Tests:

access property with prototype
for (var i=0; i<100; ++i) { if (withPrototype[i]) continue; }
access property without prototype
for (var i=0; i<100; ++i) { if (withoutPrototype[i]) continue; }
in with prototype
for (var i=0; i<100; ++i) { if (i in withPrototype) continue; }
in without prototype
for (var i=0; i<100; ++i) { if (i in withoutPrototype) continue; }
hasOwnProperty with prototype
for (var i=0; i<100; ++i) { if (hasOwnProperty.call(withPrototype, i)) continue; }
hasOwnProperty without prototype
for (var i=0; i<100; ++i) { if (hasOwnProperty.call(withoutPrototype, i)) continue; }