Run results for: indexOf vs map

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36

Browser: Chrome 67

Operating system: Mac OS X 10.12.6

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
indexOf	31270.3 Ops/sec
map with forEach	1703.8 Ops/sec
map with loop	1700.6 Ops/sec

Script Preparation code:

function hasWithIndexOf(needle, haystack) {
	return haystack.indexOf(needle) !== -1;
}

function hasWithMapForEach(needle, haystack) {
	var map = {};
	haystack.forEach(item => map[item] = true);
	return map[needle];
}

function hasWithMapLoop(needle, haystack) {
	var map = {};
	for (var i=0, len=haystack.length; i<len; ++i) {
    	map[haystack[i]] = true;
    }
	return map[needle];
}
         
var testArray = [];
for (var i=0; i<100; ++i) {
  	testArray.push('00' + i);
}

Tests:

indexOf
for (var i=0; i<100; ++i) { hasWithIndexOf('404', testArray); }
map with forEach
for (var i=0; i<100; ++i) { hasWithMapForEach('404', testArray); }
map with loop
for (var i=0; i<100; ++i) { hasWithMapLoop('404', testArray); }

Run results for: indexOf vs map

indexOf

map with forEach

map with loop