Comment by turtleyacht

Yes, some automated instrumentation equivalent of `debugger' at the start of the module's first such function, and stepping into each function down to some depth, then starting over with the next line of the module's implementation.

A partial or semi-automated, tool-assisted approach might be possible, if there were a way to restart Node.js between decisions. Each decision point writes an entry "event" that records the filename, function, caller, line number, etc. Then `debugger' is inserted before the next line, and so on.