Run results for: Unnecessary non-capturing groups

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.67 Safari/537.36

Browser: Chrome 87

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
unneededNonCaptureRE	2115198.0 Ops/sec
noNonCaptureRE	2117309.5 Ops/sec
anotherUnneededNonCapture	2780771.0 Ops/sec
anotherNoNonCapture	2189137.2 Ops/sec

Script Preparation code:

var loremString = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
var unneededNonCaptureRE = /(?:z)+/
var noNonCaptureRE = /z+/
var anotherUnneededNonCapture = /lab(?:o)rum/
var anotherNoNonCapture = /laborum/

Tests:

unneededNonCaptureRE
unneededNonCaptureRE.lastIndex = 0 unneededNonCaptureRE.exec(loremString)
noNonCaptureRE
noNonCaptureRE.lastIndex = 0 noNonCaptureRE.exec(loremString)
anotherUnneededNonCapture
anotherUnneededNonCapture.lastIndex = 0 anotherUnneededNonCapture.exec(loremString)
anotherNoNonCapture
anotherNoNonCapture.lastIndex = 0 anotherNoNonCapture.exec(loremString)

Run results for: Unnecessary non-capturing groups

https://stackoverflow.com/questions/45291700/javascript-regex-non-capture-faster-than-no-parenthesis-at-all

unneededNonCaptureRE

noNonCaptureRE

anotherUnneededNonCapture

anotherNoNonCapture