IDE with advanced code analysis?

/prog/, what's the IDE with the most advanced code analysis features out there? I'm talking about things like:

- listing all the free variables that occur in selected code term
- warning the user when he shadows a binding from the outer scope
- finding all the places where a variable gets mutated
- showing all possible execution paths through a code term

>>10

Is there an IDE smart enough to help me?

Yes, Notepad can do this. You select the lines you want to put into a function, hit Ctrl-X, move the cursor out of the function, and then hit Ctrl-V. You will have to write a function signature around it, though. Then all of your code-specific tools (including your IDE -- the above steps are not specific to Notepad!) will show you where the free variables in your new function are.

Alternatively, all of the top DDG search results for "ide refactor" which mention a specific IDE give you step-by-step instructions on how to do what you are trying to do.

"design patterns"

Bzzt! Wrong again! Explain how, exactly, "write smaller functions" is a "design pattern", because it just sounds like common fucking sense to me.
Perhaps you are not using a language particularly conducive to writing small helper functions in order to break down your problem into its component parts?