TracePoint.new(:raise) not yet supported

[eregon]

Discussed in #3679

^{Originally posted by stdedos October 2, 2024}
I am trying to build a quick pipeline for https://github.com/ConradIrwin/interception (stdedos/interception@4ff277c), but it seems that "no truffleruby variant" supports TracePoint.new(:raise)?

https://github.com/stdedos/interception/actions/runs/11141771488/job/30963350904#step:5:19

I am not very involved with ruby - but you do claim:

https://www.graalvm.org/ruby/
TruffleRuby aims to be fully compatible with the standard Ruby runtime (MRI/CRuby)

So I thought it is not far-fetched to at least ask for some quick tips 🙏

[eregon]

@stdedos Thanks for the report.
Indeed, the TracePoint :raise event is not yet supported on TruffleRuby.

It should be possible to support it but from past experience adding support for TracePoint events is a non-trivial amount of work.

[stdedos]

Why I started a discussion also was: Is there "some way" (e.g. listed in https://github.com/ConradIrwin/interception/blob/master/lib/cross_platform.rb) to use as a workaround for now?

https://github.com/ConradIrwin/interception is "somewhere in the chain" for https://github.com/ConradIrwin/pry-rescue
(ofc https://github.com/oracle/truffleruby as somewhere mentioned that there are other debugger backends that are supported as of now)

I don't have strong requirements "to do this" - as long as it is documented missing.
(e.g. idk where would I look for valid TracePoint.new arguments, except ofc trial-and-error)

[eregon]

Is there "some way" (e.g. listed in https://github.com/ConradIrwin/interception/blob/master/lib/cross_platform.rb) to use as a workaround for now?

I think there is no way currently.
I guess one could monkey-patch Kernel#raise but it will only see Ruby exceptions thrown from Ruby code, not from Java code.
The TracePoint :raise event seems to see Ruby exceptions thrown from C code:

$ ruby -e 'TracePoint.trace(:raise) { |tp| p tp }; 1 / 0'
#<TracePoint:raise -e:1>
-e:1:in `/': divided by 0 (ZeroDivisionError)
	from -e:1:in `<main>'