Run results for: Object look-up

Run details:

User agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:50.0) Gecko/20100101 Firefox/50.0

Browser: Firefox 50

Operating system: Windows 7

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
access property with prototype	1233040.5 Ops/sec
access property without prototype	1430683.5 Ops/sec
in with prototype	1104602.9 Ops/sec
in without prototype	1522130.1 Ops/sec
hasOwnProperty with prototype	248467.3 Ops/sec
hasOwnProperty without prototype	195328.2 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; }

Run results for: Object look-up

access property with prototype

access property without prototype

in with prototype

in without prototype

hasOwnProperty with prototype

hasOwnProperty without prototype