Strange Gradle crash when testing new preview implementation in 9.4.0

[ZacSweers]

Describe the bug: When testing the new preview implementation in 9.4.0, a strange crash comes from deep in Gradle that suggests it is unable to properly snapshot the MamifyClassesTask input properties.

To Reproduce Steps to reproduce the behavior:

1. Use 9.4.0 preview.
2. Observe this crash during a MamifyClassesTask run.

* What went wrong:
Execution failed for task ':app:intuneDebugMamifyClasses'.
> Cannot invoke "java.lang.CharSequence.length()" because "value" is null

* Try:
> Run with --debug option to get more log output.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:intuneDebugMamifyClasses'.
        at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:38)
        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:204)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:199)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:157)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:53)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:73)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:52)
        at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:42)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:338)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:325)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:318)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:304)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:463)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:380)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
        at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:49)
Caused by: java.lang.NullPointerException: Cannot invoke "java.lang.CharSequence.length()" because "value" is null
        at org.gradle.internal.hash.Hashing$DefaultHasher.putString(Hashing.java:413)
        at org.gradle.internal.snapshot.impl.ImmutableManagedValueSnapshot.appendToHasher(ImmutableManagedValueSnapshot.java:71)
        at org.gradle.internal.snapshot.impl.AbstractManagedValueSnapshot.appendToHasher(AbstractManagedValueSnapshot.java:52)
        at org.gradle.internal.snapshot.impl.ManagedValueSnapshot.appendToHasher(ManagedValueSnapshot.java:22)
        at org.gradle.internal.snapshot.impl.AbstractArraySnapshot.appendToHasher(AbstractArraySnapshot.java:41)
        at org.gradle.internal.snapshot.impl.ArrayValueSnapshot.appendToHasher(ArrayValueSnapshot.java:23)
        at org.gradle.internal.snapshot.impl.AbstractManagedValueSnapshot.appendToHasher(AbstractManagedValueSnapshot.java:52)
        at org.gradle.internal.snapshot.impl.ManagedValueSnapshot.appendToHasher(ManagedValueSnapshot.java:22)
        at org.gradle.internal.execution.caching.impl.DefaultCachingStateFactory.lambda$createCachingState$1(DefaultCachingStateFactory.java:59)
        at com.google.common.collect.ImmutableSortedMap.forEach(ImmutableSortedMap.java:793)
        at org.gradle.internal.execution.caching.impl.DefaultCachingStateFactory.createCachingState(DefaultCachingStateFactory.java:51)
        at org.gradle.internal.execution.steps.ResolveCachingStateStep.calculateCachingState(ResolveCachingStateStep.java:95)
        at org.gradle.internal.execution.steps.ResolveCachingStateStep.lambda$execute$0(ResolveCachingStateStep.java:67)
        at org.gradle.internal.execution.steps.ResolveCachingStateStep.execute(ResolveCachingStateStep.java:67)
        at org.gradle.internal.execution.steps.ResolveCachingStateStep.execute(ResolveCachingStateStep.java:37)
        at org.gradle.internal.execution.steps.ValidateStep.execute(ValidateStep.java:94)
        at org.gradle.internal.execution.steps.ValidateStep.execute(ValidateStep.java:49)
        at org.gradle.internal.execution.steps.CaptureStateBeforeExecutionStep.execute(CaptureStateBeforeExecutionStep.java:71)
        at org.gradle.internal.execution.steps.CaptureStateBeforeExecutionStep.execute(CaptureStateBeforeExecutionStep.java:45)
        at org.gradle.internal.execution.steps.SkipEmptyWorkStep.executeWithNonEmptySources(SkipEmptyWorkStep.java:177)
        at org.gradle.internal.execution.steps.SkipEmptyWorkStep.execute(SkipEmptyWorkStep.java:81)
        at org.gradle.internal.execution.steps.SkipEmptyWorkStep.execute(SkipEmptyWorkStep.java:53)
        at org.gradle.internal.execution.steps.RemoveUntrackedExecutionStateStep.execute(RemoveUntrackedExecutionStateStep.java:32)
        at org.gradle.internal.execution.steps.RemoveUntrackedExecutionStateStep.execute(RemoveUntrackedExecutionStateStep.java:21)
        at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsStartedStep.execute(MarkSnapshottingInputsStartedStep.java:38)
        at org.gradle.internal.execution.steps.LoadPreviousExecutionStateStep.execute(LoadPreviousExecutionStateStep.java:36)
        at org.gradle.internal.execution.steps.LoadPreviousExecutionStateStep.execute(LoadPreviousExecutionStateStep.java:23)
        at org.gradle.internal.execution.steps.CleanupStaleOutputsStep.execute(CleanupStaleOutputsStep.java:75)
        at org.gradle.internal.execution.steps.CleanupStaleOutputsStep.execute(CleanupStaleOutputsStep.java:41)
        at org.gradle.internal.execution.steps.AssignWorkspaceStep.lambda$execute$0(AssignWorkspaceStep.java:32)
        at org.gradle.api.internal.tasks.execution.TaskExecution$4.withWorkspace(TaskExecution.java:287)
        at org.gradle.internal.execution.steps.AssignWorkspaceStep.execute(AssignWorkspaceStep.java:30)
        at org.gradle.internal.execution.steps.AssignWorkspaceStep.execute(AssignWorkspaceStep.java:21)
        at org.gradle.internal.execution.steps.IdentityCacheStep.execute(IdentityCacheStep.java:37)
        at org.gradle.internal.execution.steps.IdentityCacheStep.execute(IdentityCacheStep.java:27)
        at org.gradle.internal.execution.steps.IdentifyStep.execute(IdentifyStep.java:42)
        at org.gradle.internal.execution.steps.IdentifyStep.execute(IdentifyStep.java:31)
        at org.gradle.internal.execution.impl.DefaultExecutionEngine$1.execute(DefaultExecutionEngine.java:64)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeIfValid(ExecuteActionsTaskExecuter.java:146)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:135)
        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:204)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:199)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:157)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:53)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:73)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:52)
        at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:42)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:338)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:325)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:318)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:304)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:463)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:380)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
        at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:49)

Expected behavior: I expect it not to crash Gradle's infrastructure.

Screenshots and logs: See above

Smartphone (please complete the following information): N/A

Intune App SDK for Android (please complete the following information):

• What version of the Intune SDK are you using? Are you using the latest version? 9.4.0
• What platform is your app based in (Java, Xamarin based, Cordova, etc)? N/A
• For errors during build, does the app build without Intune SDK integration? N/A
• For errors post build, does the app launch without being Intune SDK integrated? N/A
• Who is the customer? N/A
• Do you see a trend with it only being reproduced on a specific device? N/A

Additional context: I am posting a separate issue with some feedback and findings that may have a clue.

[bannus]

Thanks for the report, we are looking into this issue.

(Internal tracking #17629069)

[ZacSweers]

I figured out the cause of the issue. It's because intune plumbs the MamifyExtension straight into an input property of the mamify task. Gradle then tries to snapshot these inputs, and any string inputs not defined or with a convention cause a crash in gradle.

The solution is to make the properties in the extension be annotated accordingly with @Input and have reasonable defaults set for their conventions in the plugin constructor. Then the input in the task should just be marked as @Nested instead.

[ZacSweers]

I think it's worth mentioning that this reproduces instantly and 100% of the time. I can't really see how this would have passed any unit or manual test.

[rygo-msft]

This issue should now be fixed in the 9.7.0 SDK