How to make IntelliJ IDEA resolve webpack requires out of node_modules directory?

javascript intellij-idea reactjs webpack react-jsx

I think this should work (or so it did in my case anyway).

In IntelliJ:

Open the project
File > Project Structure
On the left hand side, select Modules
From your directory structure, select the folders where your sources are (util and src) and mark them as Resources
Click Apply

You should have code completion and documentation available now.