Benchmark: for-in vs for-of Object.keys 2

Script Preparation code:

var obj = {
  'a': 1,
  'b': 1,
  'c': 1,
  'd': 1,
  'e': 1,
  'f': 1,
  'g': 1
};

Tests:

for-in
for (let i=10000; i > 0; i--) { for (let key in obj) { let x = key in obj; } }
for-of Object.keys
for (let i=10000; i > 0; i--) { let keys = Object.keys(obj); for (let key of keys) { let x = key in obj; } }
for-of Object.keys includes
for (let i=10000; i > 0; i--) { let keys = Object.keys(obj); for (let key of keys) { let x = keys.includes(key); } }
for-of Object.keys hasOwnProperty
for (let i=10000; i > 0; i--) { let keys = Object.keys(obj); for (let key of keys) { let x = Object.hasOwnProperty(obj, key); } }

Rendered benchmark preparation results:

Previous results

Test case name	Result
for-in
for-of Object.keys
for-of Object.keys includes
for-of Object.keys hasOwnProperty

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Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.107 Safari/537.36

Browser/OS: Chrome 92 on Windows

Test name	Executions per second
for-in	143.1 Ops/sec
for-of Object.keys	114.3 Ops/sec
for-of Object.keys includes	412.4 Ops/sec
for-of Object.keys hasOwnProperty	32.4 Ops/sec

for-in vs for-of Object.keys 2 (version: 6)