Debugging aborted syntax highlighting

[danthe1st]

I am in a situation where performing some folding operations in the Java editor results in the syntax highlighting stopping at some point.

In the above image, the void keyword is not highlighted and I think the syntax highlighter ran into an issue (e.g. some sort of exception somewhere) aborting the syntax highlighting without a stack trace being printed to the console. Are there any general hints of how I could debug this kind of issue/what to look at for cases like that (where I'm already able to reproduce it)?

Note: I'm not asking where this specific problem is but how to debug these issues in general (and it only happens (in this way) with some specific changes I have locally).

[fedejeanne]

Assuming you can debug, you could either see if you walk into any method of org.eclipse.jdt.internal.compiler.problem.ProblemHandler or (a more generic approach) see if any org.eclipse.jdt.internal.compiler.problem.AbortCompilation (or a subclass) is being instantiated.

[danthe1st]

It seems like neither of them are called. I don't think it's a compiler issue but rather just a display issue (possibly within Platform UI which is a part of the reason I asked here but it could also be somewhere in JDT-UI of course) because:

• It only happens when folding/using visible regions in a certain way (Prevent IllegalStateException setting visible region with collapsed projection region #3456)
• The class compiles fine
• Clicking on void "fixes" the issue

For now, I'm trying to debug org.eclipse.jface.text.presentation.PresentationReconciler.processDamage.

[danthe1st]

After debugging org.eclipse.jface.text.presentation.PresentationReconciler.processDamage., it seems like IPresentationRepairer#createPresentation wasn't called properly for some reason so (out of curiosity) I applied #3457 which temporarily disabled redrawing which fixed the issue I was facing.