<div class="intro">
<p>This example shows how to create an asynchronous test with the YUI Test framework for testing browser-based JavaScript code.
A <code>Y.Test.Case</code></a> object is created to test the
<code>Y.Anim</code> object. The test waits until the animation is complete
before checking the settings of the animated element.</p>
</div>
<div class="example yui3-skin-sam" style="position: relative;">
{{>test-async-event-tests-source}}
</div>
<h2 class="first">Asynchronous Events Test Example</h2>
<p>This example begins by creating a namespace:</p>
```
```
<p>This namespace serves as the core object upon which others will be added (to prevent creating global objects).</p>
<h3>Creating the TestCase</h3>
<p>The first step is to create a new <code>Y.Test.Case</code>object called <code>AsyncTestCase</code>.
To do so, using the <code>Y.Test.Case</code>constructor and pass in an object literal containing information about the tests to be run:</p>
```
//name of the test case - if not provided, one is auto-generated
name : "Animation Tests",
//---------------------------------------------------------------------
// Test methods - names must begin with "test"
//---------------------------------------------------------------------
testAnimation : function (){
var myAnim = new Y.Anim({
node: '#testDiv',
to: {
width: 400
},
duration: 3,
easing: Y.Easing.easeOut
});
//assign oncomplete handler
myAnim.on("end", function(){
//tell the TestRunner to resume
this.resume(function(){
Y.Assert.areEqual(document.getElementById("testDiv").offsetWidth, 400, "Width of the DIV should be 400.");
});
}, this, true);
//start the animation
myAnim.run();
//wait until something happens
this.wait();
}
});
```
<p>The only test in the <code>Y.Test.Case</code>is called <code>testAnimation</code>. It begins by creating a new
<code>Anim</code> object that will animate the width of a <code>div</code> to 400 pixels over three seconds. An
event handler is assigned to the <code>Anim</code> object's <code>end</code> event, within which the
<code>resume()</code> method is called. A function is passed into the <code>resume()</code> method to indicate
the code to run when the test resumes, which is a test to make sure the width is 400 pixels. After that, the
<code>run()</code> method is called to begin the animation and the <code>wait()</code> method is called to
tell the <code>Y.Test.Runner</code> to wait until it is told to resume testing again. When the animation completes,
the <code>end</code> event is fired and the test resumes, assuring that the width is correct.</p>
<h3>Running the tests</h3>
<p>With all of the tests defined, the last step is to run them:</p>
```
//create the console
(new Y.Test.Console({
verbose : true,
newestOnTop : false,
filters: {
pass: true,
fail: true
}
}).render('#testLogger');
//create the logger
//run the tests
```
<p>Before running the tests, it's necessary to create a <code>Y.Test.Console</code> object to display the results (otherwise the tests would run
but you wouldn't see the results). After that, the <code>Y.Test.Runner</code> is loaded with the <code>Y.Test.Case</code>object by calling
<code>add()</code> (any number of <code>Y.Test.Case</code>and <code>TestSuite</code> objects can be added to a <code>Y.Test.Runner</code>,
this example only adds one for simplicity). The very last step is to call <code>run()</code>, which begins executing the tests in its
queue and displays the results in the <code>Y.Test.Console</code>.</p>
<h2>Complete Example Source</h2>
```
{{>test-async-event-tests-source}}
```