Run results for: Array Initialization: Constructor vs Literal

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:49.0) Gecko/20100101 Firefox/49.0

Browser: Firefox 49

Operating system: Windows

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
Literal with push	134199.2 Ops/sec
Constructor() with push	145518.3 Ops/sec
Constructor(times) with push	96207.0 Ops/sec
Literal with index	141703.3 Ops/sec
Constructor() with index	141515.1 Ops/sec
Constructor(times) with index	171571.6 Ops/sec
Literal with push and overflow	136780.5 Ops/sec
Constructor() with push and overflow	141507.3 Ops/sec
Constructor(times) with push and overflow	97361.2 Ops/sec
Literal with index and overflow	142752.6 Ops/sec
Constructor() with index and overflow	143544.8 Ops/sec
Constructor(times) with index and overflow	194902.5 Ops/sec

Script Preparation code:

var times = 500;

var noOverflow = 0,
    overflow = 1;

Tests:

Literal with push
var arr = [], arrSize = times + noOverflow; for (var i = 0; i <= arrSize; i++) { arr.push(1337); }
Constructor() with push
var arr = new Array(), arrSize = times + noOverflow; for (var i = 0; i <= arrSize; i++) { arr.push(1337); }
Constructor(times) with push
var arr = new Array(times), arrSize = times + noOverflow; for (var i = 0; i <= arrSize; i++) { arr.push(1337); }
Literal with index
var arr = [], arrSize = times + noOverflow; for (var i = 0; i <= arrSize; i++) { arr[i] = 1337; }
Constructor() with index
var arr = new Array(), arrSize = times + noOverflow; for (var i = 0; i <= arrSize; i++) { arr[i] = 1337; }
Constructor(times) with index
var arr = new Array(times), arrSize = times + noOverflow; for (var i = 0; i <= arrSize; i++) { arr[i] = 1337; }
Literal with push and overflow
var arr = [], arrSize = times + overflow; for (var i = 0; i <= arrSize; i++) { arr.push(1337); }
Constructor() with push and overflow
var arr = new Array(), arrSize = times + overflow; for (var i = 0; i <= arrSize; i++) { arr.push(1337); }
Constructor(times) with push and overflow
var arr = new Array(times), arrSize = times + overflow; for (var i = 0; i <= arrSize; i++) { arr.push(1337); }
Literal with index and overflow
var arr = [], arrSize = times + overflow; for (var i = 0; i <= arrSize; i++) { arr[i] = 1337; }
Constructor() with index and overflow
var arr = new Array(), arrSize = times + overflow; for (var i = 0; i <= arrSize; i++) { arr[i] = 1337; }
Constructor(times) with index and overflow
var arr = new Array(times), arrSize = times + overflow; for (var i = 0; i <= arrSize; i++) { arr[i] = 1337; }

Run results for: Array Initialization: Constructor vs Literal

This test should measure performance of different array initialization types

Literal with push

Constructor() with push

Constructor(times) with push

Literal with index

Constructor() with index

Constructor(times) with index

Literal with push and overflow

Constructor() with push and overflow

Constructor(times) with push and overflow

Literal with index and overflow

Constructor() with index and overflow

Constructor(times) with index and overflow