Benchmark: for-in vs object.keys loop test

Script Preparation code:

var obj = {};

for (var i=1000; i > 0; i--) {
  obj[""+i] = i;
}

Tests:

Object.keys
var ctr = 0; for (var i=100; i > 0; i--) { Object.keys(obj).forEach(key => ctr++); } console.log(ctr);
for-in
var ctr = 0; for (var i=100; i > 0; i--) { for(var key in obj) { ctr++; } } console.log(ctr);

Rendered benchmark preparation results:

Previous results

Test case name	Result
Object.keys
for-in

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Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.6 Safari/605.1.15

Browser/OS: Safari 16 on Mac OS X 10.15.7

Test name	Executions per second
Object.keys	111.5 Ops/sec
for-in	96.8 Ops/sec

for-in vs object.keys loop test (version: 0)