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

>>11

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?

Or how about just writing it all in one place so you don't have to jump all over the fucking file(s) to figure out how it works?