NPE when get test paths

!MESSAGE Error in calling delegate command handler
!STACK 0
java.lang.NullPointerException: Cannot invoke "org.eclipse.core.runtime.IPath.toOSString()" because the return value of "org.eclipse.core.resources.IFolder.getLocation()" is null
	at com.microsoft.java.test.plugin.util.ProjectTestUtils.parseTestSourcePathString(ProjectTestUtils.java:144)
	at com.microsoft.java.test.plugin.util.ProjectTestUtils.getTestSourcePaths(ProjectTestUtils.java:114)
	at com.microsoft.java.test.plugin.util.ProjectTestUtils.listTestSourcePaths(ProjectTestUtils.java:61)
	at com.microsoft.java.test.plugin.handler.TestDelegateCommandHandler.executeCommand(TestDelegateCommandHandler.java:48)
	at org.eclipse.jdt.ls.core.internal.handlers.WorkspaceExecuteCommandHandler$1.run(WorkspaceExecuteCommandHandler.java:230)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
	at org.eclipse.jdt.ls.core.internal.handlers.WorkspaceExecuteCommandHandler.executeCommand(WorkspaceExecuteCommandHandler.java:220)
	at org.eclipse.jdt.ls.core.internal.handlers.JDTLanguageServer.lambda$4(JDTLanguageServer.java:594)
	at org.eclipse.jdt.ls.core.internal.BaseJDTLanguageServer.lambda$0(BaseJDTLanguageServer.java:87)
	at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(Unknown Source)
	at java.base/java.util.concurrent.CompletableFuture$Completion.exec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool.scan(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(Unknown Source)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(Unknown Source)

Start in com.microsoft.java.test.plugin.util.ProjectTestUtils.java at parseTestSourcePathString (line 144), then trace getTestSourcePaths and listTestSourcePaths. Reproduce the delegate command failure and verify that requesting test paths for the affected folder no longer raises the reported NullPointerException.