Can't build in worktree

Not sure if this is supported, but building the Checker Framework in a git worktree fails for me. Steps to reproduce:

mkdir worktrees
cd worktrees
git clone https://github.com/typetools/checker-framework.git
cd checker-framework
git worktree add ../test-branch
cd ../test-branch
./gradlew assemble

Here's the relevant output of ./gradlew assemble.

> Task :installGitHooks FAILED
> Task :checker:processResources
> Task :annotation-file-utilities:compileJava UP-TO-DATE
> Task :annotation-file-utilities:processResources NO-SOURCE
> Task :annotation-file-utilities:classes UP-TO-DATE
> Task :annotation-file-utilities:jar UP-TO-DATE
> Task :framework:cloneTypetoolsJdk

FAILURE: Build failed with an exception.

* What went wrong:
A problem was found with the configuration of task ':installGitHooks' (type 'Copy').
  - Type 'org.gradle.api.tasks.Copy' property 'destinationDir' is not writable because '/home/jason/cftest/worktrees/test-branch/.git/hooks' ancestor '/home/jason/cftest/worktrees/test-branch/.git' is not a directory.
    
    Reason: Expected '/home/jason/cftest/worktrees/test-branch/.git' to be a directory but it's a file.
    
    Possible solution: Make sure that the 'destinationDir' is configured to a directory.
    
    Please refer to https://docs.gradle.org/7.1/userguide/validation_problems.html#cannot_write_output for more details about this problem.

* Try:
Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Exception is:
org.gradle.internal.execution.WorkValidationException: A problem was found with the configuration of task ':installGitHooks' (type 'Copy').
  - Type 'org.gradle.api.tasks.Copy' property 'destinationDir' is not writable because '/home/jason/cftest/worktrees/test-branch/.git/hooks' ancestor '/home/jason/cftest/worktrees/test-branch/.git' is not a directory.
    
    Reason: Expected '/home/jason/cftest/worktrees/test-branch/.git' to be a directory but it's a file.
    
    Possible solution: Make sure that the 'destinationDir' is configured to a directory.
    
    Please refer to https://docs.gradle.org/7.1/userguide/validation_problems.html#cannot_write_output for more details about this problem.
        at org.gradle.internal.execution.WorkValidationException$BuilderWithSummary.build(WorkValidationException.java:109)
        at org.gradle.internal.execution.WorkValidationException$BuilderWithSummary.get(WorkValidationException.java:91)
        at org.gradle.internal.execution.steps.ValidateStep.execute(ValidateStep.java:98)
        at org.gradle.internal.execution.steps.ValidateStep.execute(ValidateStep.java:51)
        at org.gradle.internal.execution.steps.CaptureStateBeforeExecutionStep.execute(CaptureStateBeforeExecutionStep.java:72)
        at org.gradle.internal.execution.steps.CaptureStateBeforeExecutionStep.execute(CaptureStateBeforeExecutionStep.java:46)
        at org.gradle.internal.execution.steps.SkipEmptyWorkStep.lambda$execute$2(SkipEmptyWorkStep.java:86)
        at org.gradle.internal.execution.steps.SkipEmptyWorkStep.execute(SkipEmptyWorkStep.java:86)
        at org.gradle.internal.execution.steps.SkipEmptyWorkStep.execute(SkipEmptyWorkStep.java:32)
        at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsStartedStep.execute(MarkSnapshottingInputsStartedStep.java:38)
        at org.gradle.internal.execution.steps.LoadExecutionStateStep.execute(LoadExecutionStateStep.java:43)
        at org.gradle.internal.execution.steps.LoadExecutionStateStep.execute(LoadExecutionStateStep.java:31)
        at org.gradle.internal.execution.steps.AssignWorkspaceStep.lambda$execute$0(AssignWorkspaceStep.java:40)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$TaskExecution$2.withWorkspace(ExecuteActionsTaskExecuter.java:284)
        at org.gradle.internal.execution.steps.AssignWorkspaceStep.execute(AssignWorkspaceStep.java:40)
        at org.gradle.internal.execution.steps.AssignWorkspaceStep.execute(AssignWorkspaceStep.java:30)
        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:44)
        at org.gradle.internal.execution.steps.IdentifyStep.execute(IdentifyStep.java:33)
        at org.gradle.internal.execution.impl.DefaultExecutionEngine$1.execute(DefaultExecutionEngine.java:76)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeIfValid(ExecuteActionsTaskExecuter.java:185)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:174)
        at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:109)
        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:56)
        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:200)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:195)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$3.execute(DefaultBuildOperationRunner.java:75)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$3.execute(DefaultBuildOperationRunner.java:68)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:153)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:68)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:62)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.lambda$call$2(DefaultBuildOperationExecutor.java:79)
        at org.gradle.internal.operations.UnmanagedBuildOperationWrapper.callWithUnmanagedSupport(UnmanagedBuildOperationWrapper.java:54)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:79)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:52)
        at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:74)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:408)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:395)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:388)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:374)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.lambda$run$0(DefaultPlanExecutor.java:127)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:191)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.executeNextNode(DefaultPlanExecutor.java:182)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:124)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
        at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:48)
        at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:56)


* Get more help at https://help.gradle.org

BUILD FAILED in 11s
7 actionable tasks: 5 executed, 2 up-to-date

It tries to copy files into the .git subdirectory of the current worktree rather than the main worktree. The getLocalRepo task seems to have the correct logic to find the right directory. When I have it print the directory it finds, it points to the main worktree as expected. However, when installGitHooks runs, the localRepo variable points to the wrong location.