Sim eles sao possiveis …
Referencia:
http://wiki.script.aculo.us/scriptaculous/show/UnitTesting
apresentacao
Exemplo
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<title>Page title</title>
<script src="path/to/prototype.js" type="text/javascript"></script>
<script src="path/to/util.js" type="text/javascript"></script>
<script src="path/to/unittest.js" type="text/javascript"></script>
<!-- other JavaScript includes -->
<link rel="stylesheet" href="path/to/test.css" type="text/css" />
</head>
<body>
<!-- Log output -->
<div id="testlog"> </div>
<!-- here go any elements you do the testing on -->
<!-- Tests -->
<script type="text/javascript" language="javascript">
// <![CDATA[
// new Test.Unit.Runner instance
new Test.Unit.Runner({
// optional setup function, run before each individual test case
setup: function() { with(this) {
// code
}},
// optional teardown function, run after each individual test case
teardown: function() { with(this) {
// code
}},
// test cases follow, each method which starts
// with "test" is considered a test case
testATest: function() { with(this) {
// code
}},
testAnotherTest: function() { with(this) {
// code
}}
}, { options });
// ]]>
</script>
</body>
</html>