Given a JS file source can I leverage the Rhino framework to determine which lines are executable and will be hit by Debugger

[avserban]

Hello,

I have a not-so-simple question, so please bare with me while I try and explain what I am trying to do.

I started to implement something similar to this: https://git.eclipse.org/c/jsdt/webtools.jsdt.git/tree/bundles/org.eclipse.wst.jsdt.debug.rhino.debugger/src/org/eclipse/wst/jsdt/debug - with some quirks and perks.

What I am trying to do: I am trying to use this to generate a LCOV unit test coverage report.

For me to do this, I can easily get which lines are hit by the debugger because this comes from the implementation of DebugFrame - easy peasy. However, the difficulty for me comes from identifying which other lines inside a file are executable in their own right - so I can easily say these are the lines I have hit with my tests and these are the lines that still need to be hit.

So far in order for me to conclude which lines are executable, I am loading the source JavaScript file and iterating through its lines. When looking at a line I am doing various string comparisons to see if said line is executable in the first place. If it is executable I am going to take note of that, if not I move on. Not an elegant solution at all, but it works.

My questions:

• If I would like to find all the lines that are executable in a script, is there a more elegant solution as opposed to the above?
• Given a script source / file path, is there a way to generate an AST that I can look at to see which lines are executable and which are not?