Can Obfuscated code refer to unobfuscated code? - javascript

I was wondering if I can obfuscate a part of my JS code and have it still refer to a set of consts or variables that I have set previously and will not obfuscate along with the remainder of the code. Is that possible, and if not, are there any alternatives to keeping the majority of my function code masked in some way and leaving the simple variable and consts to be out in the open?
I've tried obfuscating the code myself, however it seems that it refuses to run properly, or at all. So I'm not sure if I have messed up along the way or not.

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How can I access embedded ASP.NET GlobalResources in JavaScript?

I'm working on a legacy ASP.NET project, which I'm trying to massage into shape slowly, but I can't make significant changes without it all collapsing like a chocolate finger house....
I've tried to find a solution for this, but failed miserably due to the specific mix of terminology ("javascript", "embedded" and/or "resource" just give me information as to how to embed a .js file...), and the fact that it's probably a weird way of doing things.
The project makes use of App_GlobalResources for translatable strings, which is used in C# code behind, the markup and in some of the JavaScript. For example:
HTML:
Text="<%$Resources: Resources, MeasuresLabel %>"
JS:
setDialogTitle('summaryDialog', physicalElementName, Resources.Resources.Summary);
This was all working fine, until we started using NUnit for some integration testing. To make the Resources.resx available to NUnit I've followed Scott Allen's suggestion, which works for NUnit but means that the above Resources.Resources is undefined.
So, my question is with this embedded file, how can I make it accessible to the JavaScript (or is there a better way I can make it available to NUnit)?
There's an the added complication due to the code I want to access it with being in separate .js files, rather than within script tags in the .aspx files.
EDIT
After looking at it some more, the real challenge is the properties that are accessed in the JS are static. Due to the number of places these are referenced, it's not practical to add a variable for each string that's being used.
I think that JS files aren't going through the ASP.NET engine and they are served as they are, that's why Resources.Resources.Summary isn't defined in your case, while it will work when embedded inside <script> tag in .aspx file.
The only way I know around this would be to store the used resource values in global javascript variables on the .aspx page and then use them in loaded JS files.

How to find an issue when using foreign JavaScript?

My problem is quite generic: I know that I have a JavaScript issue somewhere. Now I don't know how to start searching where the problem could be. Usually I use the Firefox built-in or the Firebug Debugger. I know how to use it in general. But what I don't know is where to start. Where should I set breakpoints? I often have this kind of problem.
As an example which is my current problem: I have a page with an unordered list. Every second list item is empty for some reason. I can see that the page gets loaded with proper list items. But then some JavaScript seems to add those empty items. It's a Yii application that inserts some JavaScript directly into the HTML but let the browser also load jquery.js, bootstrap.js and yii.js. I haven't added any own JavaScript.
Now, as I said, I don't know where to start to find the problem. It might be that I have done something wrong with some configuration. But it could also be bug. I just want to figure it out somehow.
With my current issue, the best would be to have a breakpoint on a function like onInsertEmptyListItemToCounfuseDeveloper() ...
I don't want a solution to my current issue. I'd like to know in general, where and how to start finding JavaScript related problems. Especially, with third-party JS. With some applications (CMS, shops,...) there are sometimes a lot of JS files. This makes it more worser.
I hope this question is answerable and you can provide some experiences.
Not speaking 'bout the CMS right now, but in general my method is
1) If you did not add any of your onw scripts, just 3rd party, delete them all of your project e.g.
You've added jquery.js, bootstrap.js, yii.js so you remove them and then you test if all works fine, if so, add first one, for me it would've been jquery.js, test again, if no bug visible add second and so on. In this case you'll see in which file is some bug or sort of unexpected behaviour.
2) Here is the worst part, in the found file you should find the problem part. So, download the full version, not production, open it in editor, and start searching... The good news are that you don't have to look through all file, just find the event listeners in your devtolls or firebug and follow them.
All of this is just my experience , so if someone know better methods, I would like to hear 'em too.
It would depend on the code. Generally, if I have a function that is suspicious, I put breakpoints or console.log() at the beginning and end of the function and see if both are executed. Then I follow the logic down to figure out which piece is broken. It really depends on the code though.

How to decrypt a javascript file

I just discovered a virus in my computer that uses a .js file to attack. I opened the file in notepad to check out the code, but it is completely encrypted. I can see some data that makes sense (such as bhynivmao.length!=4), but the majority of the file is filled with gibberish.
There is also an autorun.inf and even though I can see some of the shell \open\command, I am not able to figure out the rest of the gibberish that is present.
Looks like both the autorun and the .js file are obfuscated the same way. Can someone please help me to get back the readable code? I am really curious to know how this thing works.
Try using something like a JS beautifier:
http://jsbeautifier.org/
It will still keep the old variable names, but will definitely make the code more readable.
You might also consider using http://jsnice.org, which uses statistical analysis of code to identify variable names. It complements http://jsbeautifier.org well by altering variable names but not structure.

Javascript stopped working after combination

Well I had lots of scripts so what I did is that I combined all of them into one script file, which contains files like Jquery library too.
But now the problem is that it has stopped working, I don't know why did this happen.
What I did is that I took every script copied and pasted it and then I gave some space under it by pressing enter a few times and then I used to paste other script, I was told this was the method to combine scripts but now the scripts don't work.
Here is the link to combined scripts http://files.cryoffalcon.com/bloghuts/uncompressed/BlogHuts%20UNCOMPRESSED.js
And the link to a live example is http://bloghutsbeta.blogspot.com/
ANSWER/SOLUTION:
Earlier I was using an older version of Jquery I think 1.5 now I changed it to latest 1.7 and that was the reason that everything stopped working. It had nothing to do with combination. I am using all scripts combined and everything is working fine But why is older version better than New that is a new question for me
First, I'd suggest you move the jquery library links out to the main page. Have one file for all of your javascript, and include the other stuff on separate lines.
Whether or not you do that, though, your problem is almost certainly some sort of unclosed bracket or semicolon missing or something similar. Javascript often reacts to stuf like that by throwing its hands up in the air and giving up. The way to fix it is to go through your file and pick a function that is not currently working, but that is easy to test for functionality. Then comment out everything else, and test to see if the function works. If not, fix the function until it does work. Then, one piece at a time, uncomment each of the other blocks, again testing to see if the initial function works. If uncommenting a block causes the thing to stop working, then that's the block that you need to fix. Depending on how long your blocks are, you may need to do this in tiers
First, don't do that with jQuery, ever. You're almost always better off pointing your script src to a public CDN somewhere.
Second, what you're trying to do is very brittle, and probably not worth troubleshooting. If you have that many JS files, you really need to use a module library (I like require.js) to give your project some structure and make it more manageable. Most libraries like this will include some sort of utility to combine and minifi your scripts safely.
This will take some work on your part to get things setup, but it should prove well worth it in the long run!

How to find unused/dead code in web projects (90% code in javascript)

I did find a very interesting tool for identify unused css definitions in a web project.
http://www.sitepoint.com/dustmeselectors/
Are there similar tools also for javascript projects?
P.S.
I know there is no program for deterministically finding unused code. But I am looking for a report to identify possible unused code. Then the last decision will always be your own.
Problem is there is no way to be really sure. Suppose the following:
The initial HTML site is practically empty. There is a lot of JS code though, which seems to be unused.
OnLoad, a function is called which launches an AJAX query to the server. The server returns a lot of HTML code, which is the body of the site. This body contains lots of JavaScript functions.
The initial body is replaced with the body received via AJAX. Suddenly, all code is used.
Static analysis utilities are therefore useless. I do not know whether there exists a browser extension that marks all JS usage from a running browser though.
You can try using tombstones to safely locate and remove dead code from your JavaScript.
https://blog.bugsnag.com/javascript-refactoring-with-bugsnag-and-tombstones/
In order to find the unused assets, to remove manually, you can use deadfile library:
https://m-izadmehr.github.io/deadfile/
It can simply find unused files, in any JS project.
Without any config, it supports ES6, JSX, and Vue files:
The one that comes to mind most quickly is Javascript LINT (http://www.javascriptlint.com/) and JSLint (http://www.jslint.com/).
Beware though: the latter hurts your feelings.

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