Run results for: Create an array with unique values - Javascript Array.reduce/Array.indexOf vs Lodash Uniq vs custom fn vs custom2

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.127 Safari/537.36

Browser: Chrome 100

Operating system: Linux

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Javascript Array.reduce/Array.indexOf	79967.0 Ops/sec
object literal/res.push(arr[i]);	338701.5 Ops/sec
object literal/res.length	353275.5 Ops/sec

Script Preparation code:

var itemsCount = 1e2;
var items = Array.from({ length: itemsCount }, () => Math.floor(Math.random() * itemsCount));

Tests:

Javascript Array.reduce/Array.indexOf
items.reduce((list, item) => list.indexOf(item) > -1 ? list : [...list, item], []);
object literal/res.push(arr[i]);
function unique(arr) { var hash = {}, result = []; for ( var i = 0, l = arr.length; i < l; ++i ) { if ( !hash.hasOwnProperty(arr[i]) ) { hash[ arr[i] ] = true; result.push(arr[i]); } } return result; } unique(items)
object literal/res.length
function unique(arr) { var hash = {}, result = []; for ( var i = 0, l = arr.length; i < l; ++i ) { if ( !hash.hasOwnProperty(arr[i]) ) { hash[ arr[i] ] = true; result[result.length] = arr[i]; } } return result; } unique(items)