Run results for: Access first key using for-in vs object.keys()

Run details:
User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/117.0.0.0 Safari/537.36
Browser: Chrome 117
Operating system: Linux
Device Platform: Desktop
Date tested: one year ago
Test name	Executions per second
for in	5558074.0 Ops/sec
object keys	1693023.4 Ops/sec
Script Preparation code:
var object = {
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    "username.1": ['"783940" is taken'],
    "username.2": ['"371395" is taken'],
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    "username.4": ['"265193" is taken'],
    "username.5": ['"674381" is taken'],
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    "username.179": ['"975595" is taken'],
    "username.180": ['"497770" is taken'],
    "username.181": ['"906992" is taken'],
    "username.182": ['"765407" is taken'],
    "username.183": ['"806852" is taken'],
    "username.184": ['"783732" is taken'],
    "username.185": ['"234423" is taken'],
    "username.186": ['"292833" is taken'],
    "username.187": ['"235675" is taken'],
    "username.188": ['"606273" is taken'],
    "username.189": ['"969380" is taken'],
    "username.190": ['"783178" is taken'],
    "username.191": ['"523958" is taken'],
    "username.192": ['"184483" is taken'],
    "username.193": ['"037698" is taken'],
    "username.195": ['"230532" is taken'],
    "username.196": ['"726840" is taken'],
    "username.197": ['"034421" is taken'],
    "username.198": ['"930613" is taken'],
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    "username.200": ['"086224" is taken'],
    "username.201": ['"075967" is taken'],
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    "username.215": ['"907886" is taken'],
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    "username.217": ['"655359" is taken'],
    "username.218": ['"644554" is taken'],
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    "username.221": ['"640872" is taken'],
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    "username.297": ['"400902" is taken'],
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    "username.314": ['"570459" is taken'],
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    "username.316": ['"563168" is taken'],
    "username.317": ['"835735" is taken'],
    "username.318": ['"584092" is taken'],
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    "username.320": ['"573128" is taken'],
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    "username.324": ['"425355" is taken'],
    "username.325": ['"448634" is taken'],
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    "username.327": ['"136557" is taken'],
    "username.328": ['"401721" is taken'],
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    "username.330": ['"923725" is taken'],
    "username.331": ['"378302" is taken'],
    "username.332": ['"792310" is taken'],
    "username.333": ['"906236" is taken'],
    "username.334": ['"162424" is taken'],
    "username.335": ['"241882" is taken'],
}
Tests:
for in
for (const key in object){ object[key] break; }
object keys
Object.keys(object)[0]
Run results for: Access first key using for-in vs object.keys()

for in

object keys
