[Bug] - Can not debug lambda expression

[mamilic]

[provide a description of the issue]
I have a stream, and I do couple of operations (filter, limit, foreach), when I try to set the breakpoint to lambda, it does not work.

Environment

• Operating System:
• JDK version:
• Visual Studio Code version:
• Java extension version:
• Java Debugger extension version:

Steps To Reproduce

1. Make lambda function
2. Set breakpoint and debug

Screencast.from.2024-03-17.08-20-55.webm

Current Result

Expected Result

Additional Informations

[testforstephen]

cannot reproduce. If you have some sample project to reproduce it consistently, feel free to share with us and reopen the issue.

lambda_breakpoint.mp4

[mamilic]

This was performed on Linux machine, could you please try just to be sure that this is only on my pc? Thanks!

[mamilic]

Hi @rgrunber, apologies for tagging you here, but you are only one who I know that uses linux, I was wondering could you please try to reproduce this with this example project - demo.zip? As of now I am not able to set inner debug breakpoint unless app is started, and also the inner breakpoint does not work, it does not stops the app when it reaches that.

Screencast.From.2024-11-22.17-28-39.mp4

[rgrunber]

Works for me. At first I thought the inline breakpoint could only be set while already debugging. I then noticed it could be set with the Debug: Inline Breakpoint command (shift+F9 by default). Works in both cases though.

Screencast.from.2024-11-25.00-05-39.mp4

I did notice the following error sent to the client error logs but might not be related since it does seem to work for me :

stacktrace

Exception in thread "Event Hub" io.reactivex.exceptions.OnErrorNotImplementedException: The exception was not handled due to missing onError handler in the subscribe() method call. Further reading: https://github.com/ReactiveX/RxJava/wiki/Error-Handling | java.lang.NullPointerException: The iterator returned a null value
	at io.reactivex.internal.functions.Functions$OnErrorMissingConsumer.accept(Functions.java:704)
	at io.reactivex.internal.functions.Functions$OnErrorMissingConsumer.accept(Functions.java:701)
	at io.reactivex.internal.observers.ConsumerSingleObserver.onError(ConsumerSingleObserver.java:46)
	at io.reactivex.internal.operators.observable.ObservableToListSingle$ToListObserver.onError(ObservableToListSingle.java:104)
	at io.reactivex.internal.observers.BasicFuseableObserver.onError(BasicFuseableObserver.java:100)
	at io.reactivex.internal.operators.observable.ObservableFromIterable$FromIterableDisposable.run(ObservableFromIterable.java:94)
	at io.reactivex.internal.operators.observable.ObservableFromIterable.subscribeActual(ObservableFromIterable.java:58)
	at io.reactivex.Observable.subscribe(Observable.java:12284)
	at io.reactivex.internal.operators.observable.ObservableFilter.subscribeActual(ObservableFilter.java:30)
	at io.reactivex.Observable.subscribe(Observable.java:12284)
	at io.reactivex.internal.operators.observable.ObservableToListSingle.subscribeActual(ObservableToListSingle.java:58)
	at io.reactivex.Single.subscribe(Single.java:3666)
	at io.reactivex.Single.subscribe(Single.java:3652)
	at io.reactivex.Single.subscribe(Single.java:3620)
	at com.microsoft.java.debug.core.Breakpoint.lambda$createBreakpointRequests$20(Breakpoint.java:407)
	at java.base/java.util.concurrent.CompletableFuture.uniComposeStage(CompletableFuture.java:1231)
	at java.base/java.util.concurrent.CompletableFuture.thenCompose(CompletableFuture.java:2385)
	at com.microsoft.java.debug.core.Breakpoint.createBreakpointRequests(Breakpoint.java:397)
	at com.microsoft.java.debug.core.Breakpoint.createBreakpointRequests(Breakpoint.java:373)
	at com.microsoft.java.debug.core.Breakpoint.lambda$install$4(Breakpoint.java:230)
	at io.reactivex.internal.observers.LambdaObserver.onNext(LambdaObserver.java:63)
	at io.reactivex.internal.operators.observable.ObservableFilter$FilterObserver.onNext(ObservableFilter.java:52)
	at io.reactivex.subjects.PublishSubject$PublishDisposable.onNext(PublishSubject.java:308)
	at io.reactivex.subjects.PublishSubject.onNext(PublishSubject.java:228)
	at com.microsoft.java.debug.core.EventHub.lambda$start$0(EventHub.java:78)
	at java.base/java.lang.Thread.run(Thread.java:1575)
Caused by: java.lang.NullPointerException: The iterator returned a null value
	at io.reactivex.internal.functions.ObjectHelper.requireNonNull(ObjectHelper.java:39)
	at io.reactivex.internal.operators.observable.ObservableFromIterable$FromIterableDisposable.run(ObservableFromIterable.java:91)
	... 20 more

[mamilic]

@rgrunber, thank you a lot!

After clean install of OS, and clean installation of VSCode it seems that everything works like a charm. 😄