Spurious Hidden Dependency Error

[AZWN]

Describe the bug
When working in Spoofax 3, a Spurious Hidden Dependency Error occurs.

Project
Occurred on an incremental build of https://github.com/MetaBorgCube/metaborg-access-modifiers/commit/9f1c5aa7c22d9b61de85cc25a7cbc94ca6d2f3fe.

Versions
Spoofax 3 0.19.3

To Reproduce
Bug happens spuriously when editing Statix files on the project mentioned above. It might be caused by the fact that there is a multi-project setup.

Observed behaviour
Build failing with the following stacktrace:

16:26:03.791 | INFO  | Worker-298: Building Workspace                     | mb.pie.runtime.tracer.LoggingTracer                | ← [1.435779] exception: mb.pie.runtime.layer.ValidationException: Hidden dependency. Cause:\ntask\n  #stratego.Front(FrontInput.Normal@1593814145{moduleIdentifier=libspoofax/term/amb, importResolutionInfo=ImportResolutionInfo@390011857{strFileGeneratingTasks=[mb.spoofax.lwb.compiler.stratego.SpoofaxStrategoResolveDependencies(ResolveDependencies$Input{rootDirectory=eclipse-resource##/acc.mod.lang.free, unarchiveDirectoryBase=eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego}), mb.spoofax.lwb.compiler.stratego.SpoofaxStrategoConfigure(eclipse-resource##/acc.mod.lang.free)], includeDirs=[eclipse-resource##/acc.mod.lang.free/src, eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego/libspoofax2.eclipse_0.19.3.jar/mb/libspoofax2/trans, eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego/libstatix.eclipse_0.19.3.jar/mb/libstatix/trans, eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego/libstatix.eclipse_0.19.3.jar/mb/libstatix/src-gen, eclipse-resource##/acc.mod.lang/src/, eclipse-resource##/acc....
mb.pie.runtime.layer.ValidationException: Hidden dependency. Cause:
task
  #stratego.Front(FrontInput.Normal@1593814145{moduleIdentifier=libspoofax/term/amb, importResolutionInfo=ImportResolutionInfo@390011857{strFileGeneratingTasks=[mb.spoofax.lwb.compiler.stratego.SpoofaxStrategoResolveDependencies(ResolveDependencies$Input{rootDirectory=eclipse-resource##/acc.mod.lang.free, unarchiveDirectoryBase=eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego}), mb.spoofax.lwb.compiler.stratego.SpoofaxStrategoConfigure(eclipse-resource##/acc.mod.lang.free)], includeDirs=[eclipse-resource##/acc.mod.lang.free/src, eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego/libspoofax2.eclipse_0.19.3.jar/mb/libspoofax2/trans, eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego/libstatix.eclipse_0.19.3.jar/mb/libstatix/trans, eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego/libstatix.eclipse_0.19.3.jar/mb/libstatix/src-gen, eclipse-resource##/acc.mod.lang/src/, eclipse-resource##/acc.mod.lang/build/generated/sources/metalang/stratego, eclipse-resource##/acc.mod.lang.free/buil...)
requires resource
  eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego/libspoofax2.eclipse_0.19.3.jar/mb/libspoofax2/trans/libspoofax/term/amb.str2
provided by task
  #mb.pie.task.archive.UnarchiveFromJar(Input{inputJarFile=java##file:/Applications/Development/Spoofax3.app/Contents/Eclipse/plugins/libspoofax2.eclipse_0.19.3.jar, outputDirectory=eclipse-resource##/acc.mod.lang.free/build/unarchive/stratego/libspoofax2.eclipse_0.19.3.jar, matcher=ExtensionsPathStringMatcher([str, str2]), unarchiveManifest=false, verifySignaturesIfSigned=false, originTask=null})
without a (transitive) task dependency from the requirer to the provider
	at mb.pie.runtime.layer.ValidationLayer.error(ValidationLayer.java:466)
	at mb.pie.runtime.layer.ValidationLayer.validateResourceRequireDep(ValidationLayer.java:213)
	at mb.pie.runtime.exec.ExecContextImpl.require(ExecContextImpl.java:176)
	at mb.pie.api.ExecContext.require(ExecContext.java:477)
	at mb.pie.api.ExecContext.require(ExecContext.java:462)
	at mb.stratego.build.strincr.ModuleImportService.getModuleAst(ModuleImportService.java:301)
	at mb.stratego.build.strincr.task.Front.getModuleAst(Front.java:663)
	at mb.stratego.build.strincr.task.Front.getModuleAst(Front.java:652)
	at mb.stratego.build.strincr.task.Front.exec(Front.java:127)
	at mb.stratego.build.strincr.task.Front.exec(Front.java:72)
	at mb.pie.api.Task.exec(Task.java:56)
	at mb.pie.runtime.exec.TaskExecutor.execInternal(TaskExecutor.java:130)
	at mb.pie.runtime.exec.TaskExecutor.exec(TaskExecutor.java:87)
	at mb.pie.runtime.exec.BottomUpRunner.exec(BottomUpRunner.java:419)
	at mb.pie.runtime.exec.BottomUpRunner.execAndSchedule(BottomUpRunner.java:132)
	at mb.pie.runtime.exec.BottomUpRunner.execScheduled(BottomUpRunner.java:119)
	at mb.pie.runtime.exec.BottomUpRunner.requireInitial(BottomUpRunner.java:82)
	at mb.pie.runtime.MixedSessionImpl.lambda$updateAffectedBy$0(MixedSessionImpl.java:72)
	at mb.pie.runtime.SessionImpl.handleException(SessionImpl.java:233)
	at mb.pie.runtime.MixedSessionImpl.updateAffectedBy(MixedSessionImpl.java:72)
	at mb.spoofax.lwb.eclipse.SpoofaxLwbBuilder.bottomUpBuild(SpoofaxLwbBuilder.java:132)
	at mb.spoofax.lwb.eclipse.SpoofaxLwbBuilderBase.incrBuild(SpoofaxLwbBuilderBase.java:88)
	at mb.spoofax.lwb.eclipse.SpoofaxLwbBuilderBase$1.run(SpoofaxLwbBuilderBase.java:59)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2292)
	at mb.spoofax.lwb.eclipse.SpoofaxLwbBuilderBase.build(SpoofaxLwbBuilderBase.java:68)
	at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:846)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
	at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:229)
	at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:277)
	at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:330)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
	at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:333)
	at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:385)
	at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:406)
	at org.eclipse.core.internal.resources.Workspace.buildInternal(Workspace.java:515)
	at org.eclipse.core.internal.resources.Workspace.build(Workspace.java:405)
	at org.eclipse.ui.actions.GlobalBuildAction$1.run(GlobalBuildAction.java:180)
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)

Expected behaviour
Build succeeding.

Additional context
Add any other context about the problem here.