Poor man's javascript testing

I'm sure someone else has done this, being so simple and old tech... But I couldn't find it anywhere, soo...

Let's say you have just finished writing a great, I mean really ground-breaking javascript library, and you call it lib.js:

Array.prototype.clear = function(){
  this.length=0;
}

And you want to test it. But how? Well, you can forget all about JsUnit, Script.aculo.us BDD, Crosscheck or the others, because now you can test your javascript with... cscript!! Yes, just write a little WSF that includes your great library:

<job>
    <script src="lib.js" language="jscript"/>
    <script language="jscript">
        var a = [1,2,3];
        a.clear();
        if (a.length != 0) {
            WScript.Echo("test failed");
            WScript.Quit(1);
        } else {
            WScript.Echo("test passed");
            WScript.Quit(0);
        }
    </script>
</job>

To execute the test, just invoke cscript on the WSF. Isn't it cool? Ok, ok, it's not cool at all, it only works for non-DOM javascript and only tests for internet explorer, BUT it's really simple and you get the potential to write the tests in another language ^[1], AND it can be easily integrated to a nant build with a <exec> task. In any case, it beats having no tests at all.

PS: Now seriously, go and check out the tools I mentioned above. GO GO!

[1] Doesn't really work most of the times. I tried ActivePython and ActiveRuby, but they don't see the functions exposed in jscript. Not to mention prototype modifications like the example above, since it doesn't make sense to other languages... VBScript seems to cooperate nicely but only for the most basic scenarios.