This is experimental. Use at your own risk.
Install Graphviz's Dot, then install callgraph from npm
npm install -g callgraph
callgraph index.js
This will generate two files in the current directory:
callgraph.png: An image representing the callgraphcallgraph.dot: A file with a Dot representation of the callgraph
Does X have walker.find_parent? Please let me know.