Benchmark: Matching regex with i flag vs lowercasing the string 2

Script Preparation code:

var str = "What if it's a much longer text here? Should we have an escape hatch? This is a Username!";
var strLower = str.toLowerCase();
var simpleNeedle = new RegExp('(user|account|log(i|o)n|net)((.)?(name|i.?d.?|log(i|o)n).?)?(.?((or|/).+|\\*|:))?$|benutzername|nome.?utente|nome (dell\')?account');
var needleWithI = new RegExp('(user|account|log(i|o)n|net)((.)?(name|i.?d.?|log(i|o)n).?)?(.?((or|/).+|\\*|:))?$|benutzername|nome.?utente|nome (dell\')?account', 'i');

Tests:

lowercasing the string
simpleNeedle.test(str.toLowerCase())
RegExp + i
needleWithI.test(str)
Already lowercased
simpleNeedle.test(strLower)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lowercasing the string
RegExp + i
Already lowercased

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 9 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

View result in a separate tab

Test name	Executions per second
lowercasing the string	10122320.0 Ops/sec
RegExp + i	14076300.0 Ops/sec
Already lowercased	12466600.0 Ops/sec

Matching regex with i flag vs lowercasing the string 2 (version: 2)

Comparing performance of: lowercasing the string vs RegExp + i vs Already lowercased

Created: 9 months ago by: Registered User

Jump to the latest result

lowercasing the string

RegExp + i

Already lowercased

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A