arccoza/index.html

## index.html
<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8"/>
	<title>Fastest way to fill a string #jsbench #jsperf</title>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/benchmark/1.0.0/benchmark.min.js"></script>
	<script src="./suite.js"></script>
</head>
<body>
	<h1>Open the console to view the results</h1>
	<h2><code>cmd + alt + j</code> or <code>ctrl + alt + j</code></h2>
</body>
</html>

## suite.js
"use strict";

(function (factory) {
	if (typeof Benchmark !== "undefined") {
		factory(Benchmark);
	} else {
		factory(require("benchmark"));
	}
})(function (Benchmark) {
	var suite = new Benchmark.Suite;

	Benchmark.prototype.setup = function () {
		let n = 120000;

		String.prototype.repeatPolyfill = function(count) {
		  'use strict';
		  if (this == null) {
		    throw new TypeError('can\'t convert ' + this + ' to object');
		  }
		  var str = '' + this;
		  count = +count;
		  if (count != count) {
		    count = 0;
		  }
		  if (count < 0) {
		    throw new RangeError('repeat count must be non-negative');
		  }
		  if (count == Infinity) {
		    throw new RangeError('repeat count must be less than infinity');
		  }
		  count = Math.floor(count);
		  if (str.length == 0 || count == 0) {
		    return '';
		  }
		  // Ensuring count is a 31-bit integer allows us to heavily optimize the
		  // main part. But anyway, most current (August 2014) browsers can't handle
		  // strings 1 << 28 chars or longer, so:
		  if (str.length * count >= 1 << 28) {
		    throw new RangeError('repeat count must not overflow maximum string size');
		  }
		  var rpt = '';
		  for (var i = 0; i < count; i++) {
		    rpt += str;
		  }
		  return rpt;
		}

		String.prototype.repeatJsCore = function repeat(count){
		  var str = this
		    , res = ''
		    , n   = count;
		  if(n < 0 || n == Infinity)throw RangeError("Count can't be negative");
		  for(;n > 0; (n >>>= 1) && (str += str))if(n & 1)res += str;
		  return res;
		};
	};


	suite.add("var str = '0'.repeat(n);", function () {
		var str = '0'.repeat(n);
	});

	suite.add("var i = 0, str = '';", function () {
		var i = 0, str = '';
		for (; i < n; str += '0', i++);
	});

	suite.add("var i = 0, str = '';", function () {
		var i = 0, str = '';
		n%2 ? (i = 1, str += '0', str) : str;
		for (; i < n; str += '00', i+=2);
	});

	suite.add("var str = '0'.repeatPolyfill(n);", function () {
		var str = '0'.repeatPolyfill(n);
	});

	suite.add("var n2 = Math.floor(n/2), i = 0;", function () {
		var n2 = Math.floor(n/2), i = 0;
		arr = new Array(n2);
		n2%2 ? (i = 1, arr[0] = 0, arr) : arr
		for (; i < n2; arr[i++] = 0, arr[i++] = 0);
		var str = arr.join('0') + (n-(2*n2) ? '00' : '0')
	});

	suite.add("var n2 = Math.floor(n/2);", function () {
		var n2 = Math.floor(n/2);
		var i = 0, str = '';
		n2%2 ? (i = 1, str += '0', str) : str;
		for (; i < n2; str += '00', i+=2);
		str = str + str + (n%2 ? '0' : '');
	});

	suite.add("var str = '0'.repeatJsCore(n);", function () {
		var str = '0'.repeatJsCore(n);
	});

	suite.on("cycle", function (evt) {
		console.log(" - " + evt.target);
	});

	suite.on("complete", function (evt) {
		console.log(new Array(30).join("-"));

		var results = evt.currentTarget.sort(function (a, b) {
			return b.hz - a.hz;
		});

		results.forEach(function (item) {
			console.log((idx + 1) + ". " + item);
		});
	});

	console.log("Fastest way to fill a string #jsbench #jsperf");
	console.log(new Array(30).join("-"));
	suite.run();
});
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8"/>
	<title>Fastest way to fill a string #jsbench #jsperf</title>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/benchmark/1.0.0/benchmark.min.js"></script>
	<script src="./suite.js"></script>
	</head>
	<body>
	<h1>Open the console to view the results</h1>
	<h2><code>cmd + alt + j</code> or <code>ctrl + alt + j</code></h2>
	</body>
	</html>
	"use strict";

	(function (factory) {
	if (typeof Benchmark !== "undefined") {
	factory(Benchmark);
	} else {
	factory(require("benchmark"));
	}
	})(function (Benchmark) {
	var suite = new Benchmark.Suite;

	Benchmark.prototype.setup = function () {
	let n = 120000;

	String.prototype.repeatPolyfill = function(count) {
	'use strict';
	if (this == null) {
	throw new TypeError('can\'t convert ' + this + ' to object');
	}
	var str = '' + this;
	count = +count;
	if (count != count) {
	count = 0;
	}
	if (count < 0) {
	throw new RangeError('repeat count must be non-negative');
	}
	if (count == Infinity) {
	throw new RangeError('repeat count must be less than infinity');
	}
	count = Math.floor(count);
	if (str.length == 0 \|\| count == 0) {
	return '';
	}
	// Ensuring count is a 31-bit integer allows us to heavily optimize the
	// main part. But anyway, most current (August 2014) browsers can't handle
	// strings 1 << 28 chars or longer, so:
	if (str.length * count >= 1 << 28) {
	throw new RangeError('repeat count must not overflow maximum string size');
	}
	var rpt = '';
	for (var i = 0; i < count; i++) {
	rpt += str;
	}
	return rpt;
	}

	String.prototype.repeatJsCore = function repeat(count){
	var str = this
	, res = ''
	, n = count;
	if(n < 0 \|\| n == Infinity)throw RangeError("Count can't be negative");
	for(;n > 0; (n >>>= 1) && (str += str))if(n & 1)res += str;
	return res;
	};
	};


	suite.add("var str = '0'.repeat(n);", function () {
	var str = '0'.repeat(n);
	});

	suite.add("var i = 0, str = '';", function () {
	var i = 0, str = '';
	for (; i < n; str += '0', i++);
	});

	suite.add("var i = 0, str = '';", function () {
	var i = 0, str = '';
	n%2 ? (i = 1, str += '0', str) : str;
	for (; i < n; str += '00', i+=2);
	});

	suite.add("var str = '0'.repeatPolyfill(n);", function () {
	var str = '0'.repeatPolyfill(n);
	});

	suite.add("var n2 = Math.floor(n/2), i = 0;", function () {
	var n2 = Math.floor(n/2), i = 0;
	arr = new Array(n2);
	n2%2 ? (i = 1, arr[0] = 0, arr) : arr
	for (; i < n2; arr[i++] = 0, arr[i++] = 0);
	var str = arr.join('0') + (n-(2*n2) ? '00' : '0')
	});

	suite.add("var n2 = Math.floor(n/2);", function () {
	var n2 = Math.floor(n/2);
	var i = 0, str = '';
	n2%2 ? (i = 1, str += '0', str) : str;
	for (; i < n2; str += '00', i+=2);
	str = str + str + (n%2 ? '0' : '');
	});

	suite.add("var str = '0'.repeatJsCore(n);", function () {
	var str = '0'.repeatJsCore(n);
	});

	suite.on("cycle", function (evt) {
	console.log(" - " + evt.target);
	});

	suite.on("complete", function (evt) {
	console.log(new Array(30).join("-"));

	var results = evt.currentTarget.sort(function (a, b) {
	return b.hz - a.hz;
	});

	results.forEach(function (item) {
	console.log((idx + 1) + ". " + item);
	});
	});

	console.log("Fastest way to fill a string #jsbench #jsperf");
	console.log(new Array(30).join("-"));
	suite.run();
	});