Benchmark: Test concat vs flatter in loop etc

HTML Preparation code:

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/3.10.1/lodash.min.js"></script>

Script Preparation code:

var arr = [];
for (var i = 0; i < 10000; i++) {
	arr.push(() => [i]);
};

Tests:

Map
let nodesFoundByClassName = _.flatten(_.map(arr, (el) => el()));
Concat
let nodesFoundByClassName = []; for (let i = 0, len = arr.length; i < len; i++) nodesFoundByClassName = nodesFoundByClassName.concat(arr[i]());
Chain
let nodesFoundByClassName = _.chain(arr).map(arr, (el) => el()).flatten().value();
Push with end flatten
let nodesFoundByClassName = []; for (let i = 0, len = arr.length; i < len; i++) nodesFoundByClassName.push(arr[i]()); nodesFoundByClassName = _.flatten(nodesFoundByClassName);
Index assign with end flatten
var i = -1; var length = arr.length; var nodesFoundByClassName = Array(length); while (++i < length) { nodesFoundByClassName[i] = arr[i](); } nodesFoundByClassName = _.flatten(nodesFoundByClassName)

Rendered benchmark preparation results:

Previous results

Test case name	Result
Map
Concat
Chain
Push with end flatten
Index assign with end flatten

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Latest run results:

Run details: (Test run date: 6 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36

Browser/OS: Chrome 59 on Linux

Test name	Executions per second
Map	631.1 Ops/sec
Concat	17.1 Ops/sec
Chain	56.7 Ops/sec
Push with end flatten	293.6 Ops/sec
Index assign with end flatten	447.3 Ops/sec

Test concat vs flatter in loop etc (version: 0)