Run results for: Object vs Map lookup with string keys

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser: Chrome 120

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 10 months ago

Test name	Executions per second
Map Lookup	5244.6 Ops/sec
Object Lookup	4305.3 Ops/sec

Script Preparation code:

window.m = new Map();
window.o = {};
for (let i = 0; i < 1000; ++i) {
  window.m.set('a' + i, i);
  window.o['a' + i] = i;
}

Tests:

Map Lookup
for (let i = 0; i < 1000; ++i) { if (window.m.get('a' + i) !== i) { console.log("bad map key"); } }
Object Lookup
for (let i = 0; i < 1000; ++i) { if (window.o['a' + i] !== i) { console.log("bad object key"); } }