Debugger does not break into code

David Huynh <[email protected]> Fri, 22 Oct 2004 09:24:37 -0400
Newsgroups	gmane.comp.mozilla.devel.jsdebugger
Organization	Another Netscape Collabra Server User
Message-ID	<[email protected]>
Hi,

I'm having problem using the JS debugger. I'm reading this guide
	http://www.svendtofte.com/code/learning_venkman/basics.php
to find out how to use the debugger, and although I've used plenty of 
debuggers in the past, I can't figure out how this Venkman thing works.

I have a pretty simple HTML file here:

<html>
<head>
	<script type="application/x-javascript"
		src="piggy-bank.js"/>
	<script language="javascript">
		function getStore2() {
			debugger
			getStore();
		}
	</script>
</head>
<body>
	<span onclick="alert('a'); getStore2();">click me</span>
</body>	
</html>

And I followed these steps:
1. start Mozilla
2. open the JS debugger and click on the Stop button (gosh, I didn't 
expect to click "stop" to _start_ my debugging task)
3. load the HTML file in Mozilla browser
4. go to the JS debugger and set the right evaluation context
5. refresh the browser. The JS debugger does break into the script file 
piggy-bank.js (containing a bunch of functions) and I let it runs through.
6. click on the span "click me". The alert "a" comes up but then nothing 
else happens. It doesn't matter if I set any breakpoint in getStore2() 
or getStore(). The debugger keyword doesn't help either.

Then I got clever and put in a function call to getStore() at the end of 
piggy-bank.js so that step #5 above would let me debug the function 
getStore(). The debugger does go into getStore(), which is something 
like this:

function getStore() {
	debugger
	var RDF = Components.classes['@mozilla.org/rdf/rdf-service;1']
		.getService(Components.interfaces.nsIRDFService);
	...
}

I hit F11 to step into at every point, but then when it reaches the 
assignment statement (RDF = ...), F11 seems to behave like F5--Venkman 
does not stop at the next statement. Frankly I don't know where it goes 
after I hit F11 at the assignment statement.

Then I got even more clever and tried to paste the body of getStore() in 
the middle of step #5 above. But alas, the little textbox in Venkman 
only takes one line of text!

I'm running Mozilla 1.7.2, Venkman 0.9.81. Venkman seems to be choking 
the daylight out of Mozilla.



So I have 2 questions:

1. What should I do if I want to debug the function getStore()?

2. How did those folks that develop various Mozilla-based applications 
refrain from killing themselves with this kind of debugging support? 
Seriously, I have great respect for the Mozilla product from an 
engineering standpoint, but the documentation and developer support 
are... Are they using some other tricks to debug their JS code?

Forgot to mention, the HTML file was originally a XUL. But Venkman 
doesn't even seem to handle XUL...

Thanks in advance!

David