regex vs toLowerCase() (v7)

Revision 7 of this benchmark created by Mike on

Description

perf difference between running a string through .toLowerCase() before applying a regex or just doing it in the regex.

Setup

var testString = "iPhone";
    var longString = "The rain in spain falls mainly in the plane. She sells sea shells on the sea SHORE."

Test runner

Ready to run.

Testing in
TestOps/sec
regex
var r = /ne/i;

var match = ~testString.search(r);
ready
.toLowerCase() first
var r = "NE";
var match = ~testString.toLowerCase().indexOf(r.toLowerCase());
ready
if already lower case
var r = "ne";
var match = ~testString.indexOf(r);
ready
if already lower case (long string/match)
var r = "shore";

var match = ~longString.indexOf(r);
ready
Long string with regex
var r = /shore/i;

var match = ~longString.search(r);
ready
Long String toLowerCase
var r = "shore";
var match = ~longString.toLowerCase().indexOf(r.toLowerCase());
ready
Must form regex in code
var j = "shore";
var r = new RegExp(j, "i");

var match = ~longString.search(r);
ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.