Array .concat() vs. .push() (v12)

Revision 12 of this benchmark created on

Description

test was buggy!

you need to create the array separately for each test to have real results as before you were mutating the same array and thus with each successive test iteration you were testing array which was bigger and bigger.

and since concat test was run after the push it was tested on even larger arrays then push making it work SUPER slow

Test runner

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Testing in
TestOps/sec
.push() (with empty array of length == 10)
var arr = new Array(10),
    toAdd = new Array(10);

for (var i = 0, iM = toAdd.length; i < iM; i++) {
 arr.push(toAdd[i]);
}
ready
.push() (array of numbers)
var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
    toAdd = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

for (var i = 0, iM = toAdd.length; i < iM; i++) {
 arr.push(toAdd[i]);
}
ready
concat strings, then split
var arr = "1 2 3 4 5 6 7 8 9 10",
    toAdd = "1 2 3 4 5 6 7 8 9 10";

var newstr = arr + " " + "toAdd";
newstr.split(" ");

 
ready
.concat() (array of numbers)
var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
    toAdd = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

arr = arr.concat(toAdd);
ready

Revisions

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