Benchmark: Object loops: for...in vs Object.keys+forEach (ES5) vs for...of (ES6) vs Object.entries (ES8)

Script Preparation code:

var obj = {};
for (let i = 0; i < 1000; i++) {
  obj['abc_' + i] = i;
}

function foo(bar) {
  return bar * 2 * 2;
}

Tests:

for...in
for (const key in obj) { if (obj.hasOwnProperty(key)) foo(obj[key]); }
Object.keys+forEach (ES5)
Object.keys(obj).forEach(function(key) { foo(obj[key]); });
for...of - keys (ES6)
for (const key of Object.keys(obj)) { foo(obj[key]); }
for...of - values (ES6)
for (const value of Object.values(obj)) { foo(value); }
for...of - entries (ES8)
for (const [key, value] of Object.entries(obj)) { foo(value); }
Object.entries (ES8)
Object.entries(obj).forEach(function(key, value) { foo(value); });

Rendered benchmark preparation results:

Previous results

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Latest run results:

Run details: (Test run date: 11 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:99.0) Gecko/20100101 Firefox/99.0

Browser/OS: Firefox 99 on Windows

Object loops: for...in vs Object.keys+forEach (ES5) vs for...of (ES6) vs Object.entries (ES8) (version: 7)