<script src='https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js'></script>
<script>
var $jq1124 = $.noConflict(true);
</script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.2.4/jquery.min.js"></script>
<script>
var $jq224 = $.noConflict(true);
</script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script>
var $jq331 = $.noConflict(true);
</script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
var $jq351 = $.noConflict(true);
</script>
<div>
<ul id="menu">
<li class="menu-item">1</li>
<li class="menu-item">2</li>
<li class="menu-item">3</li>
<li class="menu-item">4</li>
</ul>
</div>
function tests($) {
$(".menu-item").eq(2).closest("ul").css({
"background-color": "red"
}).parent().css({
"border": "1px solid blue"
}).append($("<p></p>").text("Text.").css({
"background-color": "green"
})).end().end().remove();
console.log('tests' + $);
}
tests($jq1124);
tests($jq224);
tests($jq331);
tests($jq351);
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
$jq1124 | |
$jq224 | |
$jq331 | |
$jq351 |
Test name | Executions per second |
---|---|
$jq1124 | 16454.8 Ops/sec |
$jq224 | 19772.1 Ops/sec |
$jq331 | 19220.2 Ops/sec |
$jq351 | 15705.7 Ops/sec |
Let's break down the provided benchmark definition and test cases.
Benchmark Definition
The benchmark is to measure the performance of different jQuery versions (1.12.4, 2.2.4, 3.3.1, and 3.5.1) in a specific JavaScript microbenchmark.
Script Preparation Code
The script preparation code defines a function tests
that takes a $
variable as an argument. The function targets a .menu-item
element at index 2 in the #menu
unordered list and performs several operations on it:
ul
element to red.The function also logs the $
variable in the console for debugging purposes.
Html Preparation Code
The HTML preparation code loads multiple versions of jQuery (1.12.4, 2.2.4, 3.3.1, and 3.5.1) and assigns them to variables using the $.noConflict(true)
method, which is a way to resolve conflicts between multiple versions of jQuery.
Individual Test Cases
The individual test cases define four separate tests:
tests
function with a different variable assignment ($jq1124
, $jq224
, $jq331
, and $jq351
).Pros and Cons of Different Approaches
Using multiple versions of jQuery in the same test case can lead to performance differences due to various factors such as:
$.noConflict(true)
can introduce conflicts, which may slow down execution.$jq1124
, $jq224
) might lead to name collisions and slower performance.However, using multiple versions also allows for:
Other Considerations
$.noConflict(true)
suggests that there might be conflicts between versions, but it's not explicitly mentioned in the test cases.$
variable.Alternative Approaches
If you want to benchmark only one version of jQuery, you can:
$.noConflict(true)
method and use a single variable assignment (e.g., $jq351
).Keep in mind that the MeasureThat.net benchmark is designed to compare multiple versions, so using alternative approaches might not provide the same level of insight into version-specific behavior.