322120 - javascript errors without obvious reason

Status: RESOLVED DUPLICATE of bug 311724

(Firefox :: General, defect)

Description

[Martin Hajduch]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.12) Gecko/20050915
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.12) Gecko/20050915

problem can be reproduced with firefox 1.5 on win32 and deer park (1.6a1 en) on win 32

problem CANNOT be reproduced with pre 1.5 firefox on linux, nor with mozilla 1.7.12 on win32

you can visit http://chat.hajduch.de and log in as test/test
if you open javascript console, you will see increasing number of syntax errors:

Error: syntax error
Source File: http://hajduch.de/chat/comm-messages.php
Line: 1, Column: 1
Source Code:
[["20060102155137","","",""]]^

i have alread seen bug https://bugzilla.mozilla.org/show_bug.cgi?id=302622 and the server IS returning content as text/plain

url returning content which is visible in error message is http://hajduch.de/chat/comm-messages.php

javascript processing this url is http://hajduch.de/chat/comm-main.js

corresponding code:
      try {
        newmessages=eval('('+xmlhttp.responseText+')');
      } catch (e) {}


also the page works as expected under latest firefox/deer park, but all these error messages are quite confusing and annoying


Reproducible: Always

Steps to Reproduce:
1. open http://chat.hajduch.de in latest firefox
2. log in as test/test
3. open javascript console

Actual Results:  
lots of syntax errors

Expected Results:  
no syntax errors (as in previous versions of mozilla/firefox)

i have tried to reproduce it locally by opening page: 

<html>
<head>
<script>
var response='[["20060102153337","martin","","ha ha"],["20060102154201","martin","","ahoj"],["20060102154206","","",""]]';
var test=eval('('+response+')');
</script>
</head>
<body>
loaded
</body>
</html>

but the problem doesn't occur

Comment 1

[Jesse Ruderman]

I see the syntax error messages in the JavaScript Console on Mac too.

Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8) Gecko/20051224 Firefox/1.5.

Comment 2

[Jesse Ruderman]

Those look like XML syntax errors (not JavaScript syntax errors) to me.  I'm guessing the

  xmlhttp.overrideMimeType('text/xml');

in http://hajduch.de/chat/comm.js makes Firefox try to treat the file as XML and give up when it isn't.

*** This bug has been marked as a duplicate of 311724 ***