Another `ConcurrentModificationException` when running `bloopInstall`

[jvican]

Describe the bug

When running bloopInstall in an internal project, I'm getting ConcurrentModificationException errors. In the past, we've had similar errors and fixed them by adding synchronized in the right places (cc @Arthurm1). However, we still have access issues.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':axion:axion-log-v2:bloopInstall'.
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.lambda$executeIfValid$1(ExecuteActionsTaskExecuter.java:130)
        at org.gradle.internal.Try$Failure.ifSuccessfulOrElse(Try.java:293)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeIfValid(ExecuteActionsTaskExecuter.java:128)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:116)
        at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:46)
        at org.gradle.api.internal.tasks.execution.ResolveTaskExecutionModeExecuter.execute(ResolveTaskExecutionModeExecuter.java:51)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:57)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:74)
        at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:36)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.executeTask(EventFiringTaskExecuter.java:77)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:55)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:52)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:209)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:204)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:166)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:53)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:52)
        at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:42)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:331)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:318)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.lambda$execute$0(DefaultTaskExecutionGraph.java:314)
        at org.gradle.internal.operations.CurrentBuildOperationRef.with(CurrentBuildOperationRef.java:85)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:314)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:303)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:459)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:376)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
        at org.gradle.internal.concurrent.AbstractManagedExecutor$1.run(AbstractManagedExecutor.java:48)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
        at java.base/java.lang.Thread.run(Thread.java:1583)
Caused by: java.util.ConcurrentModificationException
        at java.base/java.util.LinkedHashMap$LinkedHashIterator.nextNode(LinkedHashMap.java:1023)
        at java.base/java.util.LinkedHashMap$LinkedKeyIterator.next(LinkedHashMap.java:1046)
        at org.gradle.api.internal.collections.SortedSetElementSource.realizePending(SortedSetElementSource.java:130)
        at org.gradle.api.internal.collections.FilteredElementSource.iterator(FilteredElementSource.java:149)
        at org.gradle.api.internal.collections.FilteredElementSource.isEmpty(FilteredElementSource.java:81)
        at org.gradle.api.internal.DefaultDomainObjectCollection.isEmpty(DefaultDomainObjectCollection.java:353)
        at org.gradle.api.internal.tasks.DefaultTaskCollection_Decorated.isEmpty(Unknown Source)
        at org.gradle.api.internal.DelegatingDomainObjectSet.isEmpty(DelegatingDomainObjectSet.java:140)
        at org.gradle.api.internal.tasks.DefaultRealizableTaskCollection_Decorated.isEmpty(Unknown Source)
        at scala.collection.convert.JavaCollectionWrappers$JSetWrapper.knownSize(JavaCollectionWrappers.scala:223)
        at scala.collection.immutable.Set$.from(Set.scala:99)
        at scala.collection.IterableOnceOps.toSet(IterableOnce.scala:1469)
        at scala.collection.IterableOnceOps.toSet$(IterableOnce.scala:1469)
        at scala.collection.AbstractIterable.toSet(Iterable.scala:935)
        at bloop.integrations.gradle.model.BloopConverter.tasksWithType(BloopConverter.scala:555)
        at bloop.integrations.gradle.model.BloopConverter.$anonfun$getArchiveSourceSetMap$1(BloopConverter.scala:587)
        at scala.collection.StrictOptimizedIterableOps.flatMap(StrictOptimizedIterableOps.scala:118)
        at scala.collection.StrictOptimizedIterableOps.flatMap$(StrictOptimizedIterableOps.scala:105)
        at scala.collection.convert.JavaCollectionWrappers$JSetWrapper.flatMap(JavaCollectionWrappers.scala:215)
        at bloop.integrations.gradle.model.BloopConverter.getArchiveSourceSetMap(BloopConverter.scala:586)
        at bloop.integrations.gradle.model.BloopConverter.toBloopConfig(BloopConverter.scala:317)
        at bloop.integrations.gradle.tasks.ScalaJavaInstall$.generateBloopConfiguration(BloopInstallTask.scala:104)
        at bloop.integrations.gradle.tasks.ScalaJavaInstall$.$anonfun$install$1(BloopInstallTask.scala:88)
        at bloop.integrations.gradle.tasks.ScalaJavaInstall$.$anonfun$install$1$adapted(BloopInstallTask.scala:80)
        at scala.collection.immutable.Set$Set3.foreach(Set.scala:261)
        at bloop.integrations.gradle.tasks.ScalaJavaInstall$.install(BloopInstallTask.scala:80)
        at bloop.integrations.gradle.tasks.BloopInstallTask.runBloopPlugin(BloopInstallTask.scala:65)
        at bloop.integrations.gradle.tasks.BloopInstallTask.run(BloopInstallTask.scala:41)
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
        at java.base/java.lang.reflect.Method.invoke(Method.java:580)
        at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:125)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.doExecute(StandardTaskAction.java:58)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:51)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:29)
        at org.gradle.api.internal.tasks.execution.TaskExecution$3.run(TaskExecution.java:244)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$1.execute(DefaultBuildOperationRunner.java:29)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$1.execute(DefaultBuildOperationRunner.java:26)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:166)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.run(DefaultBuildOperationRunner.java:47)
        at org.gradle.api.internal.tasks.execution.TaskExecution.executeAction(TaskExecution.java:229)
        at org.gradle.api.internal.tasks.execution.TaskExecution.executeActions(TaskExecution.java:212)
        at org.gradle.api.internal.tasks.execution.TaskExecution.executeWithPreviousOutputFiles(TaskExecution.java:195)
        at org.gradle.api.internal.tasks.execution.TaskExecution.execute(TaskExecution.java:162)
        at org.gradle.internal.execution.steps.ExecuteStep.executeInternal(ExecuteStep.java:105)
        at org.gradle.internal.execution.steps.ExecuteStep.access$000(ExecuteStep.java:44)
        at org.gradle.internal.execution.steps.ExecuteStep$1.call(ExecuteStep.java:59)
        at org.gradle.internal.execution.steps.ExecuteStep$1.call(ExecuteStep.java:56)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:209)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:204)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:166)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:53)
        at org.gradle.internal.execution.steps.ExecuteStep.execute(ExecuteStep.java:56)
        at org.gradle.internal.execution.steps.ExecuteStep.execute(ExecuteStep.java:44)
        at org.gradle.internal.execution.steps.CancelExecutionStep.execute(CancelExecutionStep.java:42)
        at org.gradle.internal.execution.steps.TimeoutStep.executeWithoutTimeout(TimeoutStep.java:75)
        at org.gradle.internal.execution.steps.TimeoutStep.execute(TimeoutStep.java:55)
        at org.gradle.internal.execution.steps.PreCreateOutputParentsStep.execute(PreCreateOutputParentsStep.java:50)
        at org.gradle.internal.execution.steps.PreCreateOutputParentsStep.execute(PreCreateOutputParentsStep.java:28)
        at org.gradle.internal.execution.steps.RemovePreviousOutputsStep.execute(RemovePreviousOutputsStep.java:67)
        at org.gradle.internal.execution.steps.RemovePreviousOutputsStep.execute(RemovePreviousOutputsStep.java:37)
        at org.gradle.internal.execution.steps.BroadcastChangingOutputsStep.execute(BroadcastChangingOutputsStep.java:61)
        at org.gradle.internal.execution.steps.BroadcastChangingOutputsStep.execute(BroadcastChangingOutputsStep.java:26)
        at org.gradle.internal.execution.steps.CaptureOutputsAfterExecutionStep.execute(CaptureOutputsAfterExecutionStep.java:69)
        at org.gradle.internal.execution.steps.CaptureOutputsAfterExecutionStep.execute(CaptureOutputsAfterExecutionStep.java:46)
        at org.gradle.internal.execution.steps.ResolveInputChangesStep.execute(ResolveInputChangesStep.java:40)
        at org.gradle.internal.execution.steps.ResolveInputChangesStep.execute(ResolveInputChangesStep.java:29)
        at org.gradle.internal.execution.steps.BuildCacheStep.executeWithoutCache(BuildCacheStep.java:189)
        at org.gradle.internal.execution.steps.BuildCacheStep.lambda$execute$1(BuildCacheStep.java:75)
        at org.gradle.internal.Either$Right.fold(Either.java:175)
        at org.gradle.internal.execution.caching.CachingState.fold(CachingState.java:62)
        at org.gradle.internal.execution.steps.BuildCacheStep.execute(BuildCacheStep.java:73)
        at org.gradle.internal.execution.steps.BuildCacheStep.execute(BuildCacheStep.java:48)
        at org.gradle.internal.execution.steps.StoreExecutionStateStep.execute(StoreExecutionStateStep.java:46)
        at org.gradle.internal.execution.steps.StoreExecutionStateStep.execute(StoreExecutionStateStep.java:35)
        at org.gradle.internal.execution.steps.SkipUpToDateStep.executeBecause(SkipUpToDateStep.java:75)
        at org.gradle.internal.execution.steps.SkipUpToDateStep.lambda$execute$2(SkipUpToDateStep.java:53)
        at java.base/java.util.Optional.orElseGet(Optional.java:364)
        at org.gradle.internal.execution.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:53)
        at org.gradle.internal.execution.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:35)
        at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsFinishedStep.execute(MarkSnapshottingInputsFinishedStep.java:37)
        at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsFinishedStep.execute(MarkSnapshottingInputsFinishedStep.java:27)
        at org.gradle.internal.execution.steps.ResolveIncrementalCachingStateStep.executeDelegate(ResolveIncrementalCachingStateStep.java:49)
        at org.gradle.internal.execution.steps.ResolveIncrementalCachingStateStep.executeDelegate(ResolveIncrementalCachingStateStep.java:27)
        at org.gradle.internal.execution.steps.AbstractResolveCachingStateStep.execute(AbstractResolveCachingStateStep.java:71)
        at org.gradle.internal.execution.steps.AbstractResolveCachingStateStep.execute(AbstractResolveCachingStateStep.java:39)
        at org.gradle.internal.execution.steps.ResolveChangesStep.execute(ResolveChangesStep.java:65)
        at org.gradle.internal.execution.steps.ResolveChangesStep.execute(ResolveChangesStep.java:36)
        at org.gradle.internal.execution.steps.ValidateStep.execute(ValidateStep.java:107)
        at org.gradle.internal.execution.steps.ValidateStep.execute(ValidateStep.java:56)
        at org.gradle.internal.execution.steps.AbstractCaptureStateBeforeExecutionStep.execute(AbstractCaptureStateBeforeExecutionStep.java:64)
        at org.gradle.internal.execution.steps.AbstractCaptureStateBeforeExecutionStep.execute(AbstractCaptureStateBeforeExecutionStep.java:43)
        at org.gradle.internal.execution.steps.AbstractSkipEmptyWorkStep.executeWithNonEmptySources(AbstractSkipEmptyWorkStep.java:125)
        at org.gradle.internal.execution.steps.AbstractSkipEmptyWorkStep.execute(AbstractSkipEmptyWorkStep.java:56)
        at org.gradle.internal.execution.steps.AbstractSkipEmptyWorkStep.execute(AbstractSkipEmptyWorkStep.java:36)
        at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsStartedStep.execute(MarkSnapshottingInputsStartedStep.java:38)
        at org.gradle.internal.execution.steps.LoadPreviousExecutionStateStep.execute(LoadPreviousExecutionStateStep.java:36)
        at org.gradle.internal.execution.steps.LoadPreviousExecutionStateStep.execute(LoadPreviousExecutionStateStep.java:23)
        at org.gradle.internal.execution.steps.HandleStaleOutputsStep.execute(HandleStaleOutputsStep.java:75)
        at org.gradle.internal.execution.steps.HandleStaleOutputsStep.execute(HandleStaleOutputsStep.java:41)
        at org.gradle.internal.execution.steps.AssignMutableWorkspaceStep.lambda$execute$0(AssignMutableWorkspaceStep.java:35)
        at org.gradle.api.internal.tasks.execution.TaskExecution$4.withWorkspace(TaskExecution.java:289)
        at org.gradle.internal.execution.steps.AssignMutableWorkspaceStep.execute(AssignMutableWorkspaceStep.java:31)
        at org.gradle.internal.execution.steps.AssignMutableWorkspaceStep.execute(AssignMutableWorkspaceStep.java:22)
        at org.gradle.internal.execution.steps.ChoosePipelineStep.execute(ChoosePipelineStep.java:40)
        at org.gradle.internal.execution.steps.ChoosePipelineStep.execute(ChoosePipelineStep.java:23)
        at org.gradle.internal.execution.steps.ExecuteWorkBuildOperationFiringStep.lambda$execute$2(ExecuteWorkBuildOperationFiringStep.java:67)
        at java.base/java.util.Optional.orElseGet(Optional.java:364)
        at org.gradle.internal.execution.steps.ExecuteWorkBuildOperationFiringStep.execute(ExecuteWorkBuildOperationFiringStep.java:67)
        at org.gradle.internal.execution.steps.ExecuteWorkBuildOperationFiringStep.execute(ExecuteWorkBuildOperationFiringStep.java:39)
        at org.gradle.internal.execution.steps.IdentityCacheStep.execute(IdentityCacheStep.java:46)
        at org.gradle.internal.execution.steps.IdentityCacheStep.execute(IdentityCacheStep.java:34)
        at org.gradle.internal.execution.steps.IdentifyStep.execute(IdentifyStep.java:48)
        at org.gradle.internal.execution.steps.IdentifyStep.execute(IdentifyStep.java:35)
        at org.gradle.internal.execution.impl.DefaultExecutionEngine$1.execute(DefaultExecutionEngine.java:61)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeIfValid(ExecuteActionsTaskExecuter.java:127)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:116)
        at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:46)
        at org.gradle.api.internal.tasks.execution.ResolveTaskExecutionModeExecuter.execute(ResolveTaskExecutionModeExecuter.java:51)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:57)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:74)
        at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:36)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.executeTask(EventFiringTaskExecuter.java:77)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:55)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:52)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:209)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:204)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:166)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:53)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:52)
        at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:42)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:331)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:318)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.lambda$execute$0(DefaultTaskExecutionGraph.java:314)
        at org.gradle.internal.operations.CurrentBuildOperationRef.with(CurrentBuildOperationRef.java:85)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:314)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:303)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:459)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:376)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
        at org.gradle.internal.concurrent.AbstractManagedExecutor$1.run(AbstractManagedExecutor.java:48)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
        at java.base/java.lang.Thread.run(Thread.java:1583)

Expected behavior

Works without errors.

Operating system

macOS

Version of Gradle

Gradle 9

Version of gradle-bloop

latest

Version of Bloop

2.0.7

[Arthurm1]

@jvican I assume you've got your own local build because the line numbers don't match.

Do you have project.synchronized around that area like...
https://github.com/scalacenter/gradle-bloop/blob/main/src/main/scala/bloop/integrations/gradle/model/BloopConverter.scala#L545-L550

I've not tried this with Gradle 9. I think it's still a while away as some of the methods that have been removed aren't even marked as deprecated yet.

[jvican]

I assume you've got your own local build because the line numbers don't match.

Yeah, I had to fork off and apply hot changes to main to fix the fact that Gradle and some of our internal tooling folks decided to force eager classpath evaluation through classpath transforms, here's a pointer to one of the changes that breaks gradle-bloop. This is why I tried to change the way gradle-bloop works in this PR, which I haven't had the time to follow up on. Ultimately, we need to change a little bit of the foundations of the gradle-bloop so it works with Gradle 9 holistically.

Do you have project.synchronized around that area like...

Yup: https://github.com/jvican/gradle-bloop/blob/main/src/main/scala/bloop/integrations/gradle/model/BloopConverter.scala#L552

Same call-sites for tasksWithType between my fork and this one. In fact, you can even see tasksWithType in the error stack trace.

This ConcurrentModificationException seems to be caused by some other error. Looking at the stack trace, I wonder if we need to do this instead:

  private def tasksWithType[T <: Task](project: Project, clazz: Class[T]): Set[T] = {
    // Gradle gives concurrentmodification exceptions if multiple threads resolve the tasks at once which happens on multi-project builds
    project.synchronized {
      val tasksCollection = project.getTasks.withType(clazz)
      tasksCollection.synchronized { tasksCollection.asScala.toSet }
    }
  }

Looks like something like this should remove this error? Let me know your thoughts.

[Arthurm1]

Maybe 🤷 . I did have another project like this where I used project.getRootProject.synchronized

[Arthurm1]

@jvican
I've been doing some work on Gradle Build Server, Microsoft's Gradle BSP.

At the moment Gradle doesn't supply Scala diagnostics nor does it consistently supply Java diagnostics, so it's a while before Metals can use it as a build server. Metals could use it to produce the .bloop files though.

I have forked the project and added Bloop Exporter

It has a couple of advantages over Gradle Bloop...

1. It's pure Java so no worries about plugin classpath clashes with other scala based plugins
2. It uses Gradle Build Actions which means that projects are automatically processed concurrently.

I'd be interested to see if it works for you, whether there are any issues and whether it improves performance.

You can run

coursier launch io.github.arthurm1.gradle.bsp:server:0.7.0 -r https://repo.gradle.org/gradle/libs-releases -M com.microsoft.java.bs.core.BloopExporter

from your Gradle project's directory.

Be aware that it will won't clear the .bloop dir but it will overwrite your .bloop/*.json files.

It's early days - I haven't made it very configurable and I haven't tested it with all the tests in Gradle Bloop

[jvican]

Hey @Arthurm1 - that's pretty cool. I didn't even know that Microsoft had a BSP implementation for gradle!

Using build actions is neat. Are you planning to make more improvements to the BloopExporter fork? Curious if you're planning to try to get that merged to the parent project, or just keep it for personal use.

[Arthurm1]

@jvican I won't be upstreaming my changes as I don't think MS have any plans for more development. They use it here as a way of getting the projects (source, classpath, modules) into VSCode Java.

I'll look to see if it's a good fit to replace the Metals bloopInstall once I've polished it a bit more. And also give it as an option to run Metals against as a full BSP server but Gradle have only just added a way to get diagnostics out so that won't be happening soon.