main-eisop NPE: Cannot invoke "com.sun.source.tree.Tree.getKind()" because "tree" is null

[cpovirk]

Seen in a variety of Guava classes, such as FluentFuture.

This might be the only crash that I've seen so far in my internal testing. But as noted in #159, one crash could be hiding others :)

For the moment, I'm going to dump the stack trace below. Then I'm going to see if it still reproduces with my fix for #159 in place, as I see inheritOverriddenDeclAnnos in the stack in both.

  Last visited tree at line 81 column 1:
  @DoNotMock("Use FluentFuture.from(Futures.immediate*Future) or SettableFuture")
  Exception: java.lang.NullPointerException: Cannot invoke "com.sun.source.tree.Tree.getKind()" because "tree" is null; java.lang.NullPointerException: Cannot invoke "com.sun.source.tree.Tree.getKind()" because "tree" is null
  	at jdk.compiler/com.sun.source.util.TreePath.<init>(TreePath.java:118)
  	at jdk.compiler/com.sun.source.util.TreePath.<init>(TreePath.java:109)
  	at jdk.compiler/com.sun.source.util.TreePath.getPath(TreePath.java:50)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.getPath(AnnotatedTypeFactory.java:3982)
  	at org.checkerframework.framework.util.defaults.QualifierDefaults.nearestEnclosingExceptLocal(QualifierDefaults.java:503)
  	at org.checkerframework.framework.util.defaults.QualifierDefaults.applyDefaults(QualifierDefaults.java:581)
  	at org.checkerframework.framework.util.defaults.QualifierDefaults.annotate(QualifierDefaults.java:489)
  	at org.checkerframework.framework.type.GenericAnnotatedTypeFactory.addComputedTypeAnnotations(GenericAnnotatedTypeFactory.java:2062)
  	at org.checkerframework.framework.type.GenericAnnotatedTypeFactory.addComputedTypeAnnotations(GenericAnnotatedTypeFactory.java:1991)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.getAnnotatedTypeFromTypeTree(AnnotatedTypeFactory.java:1556)
  	at org.checkerframework.framework.type.SupertypeFinder$SupertypeFindingVisitor.supertypesFromTree(SupertypeFinder.java:338)
  	at org.checkerframework.framework.type.SupertypeFinder$SupertypeFindingVisitor.visitDeclared(SupertypeFinder.java:191)
  	at org.checkerframework.framework.type.SupertypeFinder.directSupertypes(SupertypeFinder.java:63)
  	at org.checkerframework.framework.type.AnnotatedTypeMirror$AnnotatedDeclaredType.directSupertypes(AnnotatedTypeMirror.java:1137)
  	at org.checkerframework.framework.util.AnnotatedTypes.getSuperTypes(AnnotatedTypes.java:646)
  	at org.checkerframework.framework.util.AnnotatedTypes.overriddenMethods(AnnotatedTypes.java:667)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.inheritOverriddenDeclAnnos(AnnotatedTypeFactory.java:4358)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.getDeclAnnotations(AnnotatedTypeFactory.java:4296)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.getDeclAnnotation(AnnotatedTypeFactory.java:4219)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.getDeclAnnotation(AnnotatedTypeFactory.java:4197)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.getDeclAnnotation(AnnotatedTypeFactory.java:4117)
  	at org.checkerframework.framework.util.defaults.QualifierDefaults.defaultsAtDirect(QualifierDefaults.java:765)
  	at org.checkerframework.framework.util.defaults.QualifierDefaults.defaultsAt(QualifierDefaults.java:713)
  	at org.checkerframework.framework.util.defaults.QualifierDefaults.defaultsAt(QualifierDefaults.java:727)
  	at org.checkerframework.framework.util.defaults.QualifierDefaults.applyDefaultsElement(QualifierDefaults.java:855)
  	at org.checkerframework.framework.util.defaults.QualifierDefaults.annotate(QualifierDefaults.java:479)
  	at org.checkerframework.framework.type.GenericAnnotatedTypeFactory.addComputedTypeAnnotations(GenericAnnotatedTypeFactory.java:2292)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.getAnnotatedType(AnnotatedTypeFactory.java:1441)
  	at com.google.jspecify.nullness.NullSpecAnnotatedTypeFactory.getUpperBounds(NullSpecAnnotatedTypeFactory.java:708)
  	at com.google.jspecify.nullness.NullSpecAnnotatedTypeFactory.nullnessEstablishingPathExists(NullSpecAnnotatedTypeFactory.java:681)
  	at com.google.jspecify.nullness.NullSpecAnnotatedTypeFactory.isNullExclusiveUnderEveryParameterization(NullSpecAnnotatedTypeFactory.java:621)
  	at com.google.jspecify.nullness.NullSpecAnnotatedTypeFactory$NullSpecTypeVariableSubstitutor.substituteTypeVariable(NullSpecAnnotatedTypeFactory.java:855)
  	at org.checkerframework.framework.type.TypeVariableSubstitutor$Visitor.visitTypeVariable(TypeVariableSubstitutor.java:173)
  	at org.checkerframework.framework.type.TypeVariableSubstitutor$Visitor.visitTypeVariable(TypeVariableSubstitutor.java:82)
  	at org.checkerframework.framework.type.AnnotatedTypeMirror$AnnotatedTypeVariable.accept(AnnotatedTypeMirror.java:1861)
  	at org.checkerframework.framework.type.AnnotatedTypeCopier.visit(AnnotatedTypeCopier.java:102)
  	at org.checkerframework.framework.type.AnnotatedTypeCopier.lambda$visitDeclared$0(AnnotatedTypeCopier.java:127)
  	at org.checkerframework.org.plumelib.util.CollectionsPlume.mapList(CollectionsPlume.java:444)
  	at org.checkerframework.framework.type.AnnotatedTypeCopier.visitDeclared(AnnotatedTypeCopier.java:126)
  	at org.checkerframework.framework.type.AnnotatedTypeCopier.visitDeclared(AnnotatedTypeCopier.java:44)
  	at org.checkerframework.framework.type.AnnotatedTypeMirror$AnnotatedDeclaredType.accept(AnnotatedTypeMirror.java:1058)
  	at org.checkerframework.framework.type.AnnotatedTypeCopier.visit(AnnotatedTypeCopier.java:102)
  	at org.checkerframework.framework.type.AnnotatedTypeCopier.visitExecutable(AnnotatedTypeCopier.java:202)
  	at org.checkerframework.framework.type.AnnotatedTypeCopier.visitExecutable(AnnotatedTypeCopier.java:44)
  	at org.checkerframework.framework.type.AnnotatedTypeMirror$AnnotatedExecutableType.accept(AnnotatedTypeMirror.java:1265)
  	at org.checkerframework.framework.type.AnnotatedTypeCopier.visit(AnnotatedTypeCopier.java:95)
  	at org.checkerframework.framework.type.TypeVariableSubstitutor.substitute(TypeVariableSubstitutor.java:34)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.methodFromUse(AnnotatedTypeFactory.java:2591)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.methodFromUse(AnnotatedTypeFactory.java:2503)
  	at org.checkerframework.framework.type.GenericAnnotatedTypeFactory.methodFromUse(GenericAnnotatedTypeFactory.java:2298)
  	at org.checkerframework.framework.type.TypeFromExpressionVisitor.visitMethodInvocation(TypeFromExpressionVisitor.java:413)
  	at org.checkerframework.framework.type.TypeFromExpressionVisitor.visitMethodInvocation(TypeFromExpressionVisitor.java:81)
  	at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1832)
  	at jdk.compiler/com.sun.source.util.SimpleTreeVisitor.visit(SimpleTreeVisitor.java:81)
  	at org.checkerframework.framework.type.TypeFromTree.fromExpression(TypeFromTree.java:42)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.fromExpression(AnnotatedTypeFactory.java:1843)
  	at org.checkerframework.framework.type.AnnotatedTypeFactory.getAnnotatedType(AnnotatedTypeFactory.java:1486)
  	at org.checkerframework.framework.flow.CFAbstractTransfer.getValueFromFactory(CFAbstractTransfer.java:215)
  	at org.checkerframework.framework.flow.CFAbstractTransfer.visitMethodInvocation(CFAbstractTransfer.java:999)
  	at com.google.jspecify.nullness.NullSpecTransfer.visitMethodInvocation(NullSpecTransfer.java:152)
  	at com.google.jspecify.nullness.NullSpecTransfer.visitMethodInvocation(NullSpecTransfer.java:75)
  	at org.checkerframework.dataflow.cfg.node.MethodInvocationNode.accept(MethodInvocationNode.java:124)
  	at org.checkerframework.dataflow.analysis.AbstractAnalysis.callTransferFunction(AbstractAnalysis.java:356)
  	at org.checkerframework.dataflow.analysis.ForwardAnalysisImpl.callTransferFunction(ForwardAnalysisImpl.java:393)
  	at org.checkerframework.dataflow.analysis.ForwardAnalysisImpl.performAnalysisBlock(ForwardAnalysisImpl.java:157)
  	at org.checkerframework.dataflow.analysis.ForwardAnalysisImpl.performAnalysis(ForwardAnalysisImpl.java:110)
  	at org.checkerframework.framework.flow.CFAbstractAnalysis.performAnalysis(CFAbstractAnalysis.java:150)
  	at org.checkerframework.framework.type.GenericAnnotatedTypeFactory.analyze(GenericAnnotatedTypeFactory.java:1623)
  	at org.checkerframework.framework.type.GenericAnnotatedTypeFactory.performFlowAnalysis(GenericAnnotatedTypeFactory.java:1513)
  	at org.checkerframework.framework.type.GenericAnnotatedTypeFactory.checkAndPerformFlowAnalysis(GenericAnnotatedTypeFactory.java:2100)
  	at org.checkerframework.framework.type.GenericAnnotatedTypeFactory.preProcessClassTree(GenericAnnotatedTypeFactory.java:435)
  	at com.google.jspecify.nullness.NullSpecAnnotatedTypeFactory.preProcessClassTree(NullSpecAnnotatedTypeFactory.java:1684)
  	at org.checkerframework.common.basetype.BaseTypeVisitor.visitClass(BaseTypeVisitor.java:591)
  	at org.checkerframework.common.basetype.BaseTypeVisitor.visitClass(BaseTypeVisitor.java:195)
  	at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:855)
  	at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:66)
  	at org.checkerframework.framework.source.SourceVisitor.visit(SourceVisitor.java:89)
  	at org.checkerframework.framework.source.SourceChecker.typeProcess(SourceChecker.java:1136)
  	at org.checkerframework.common.basetype.BaseTypeChecker.typeProcess(BaseTypeChecker.java:556)
  	at com.google.jspecify.nullness.NullSpecChecker.typeProcess(NullSpecChecker.java:106)
  	at org.checkerframework.javacutil.AbstractTypeProcessor$AttributionTaskListener.finished(AbstractTypeProcessor.java:193)
  	at jdk.compiler/com.sun.tools.javac.api.ClientCodeWrapper$WrappedTaskListener.finished(ClientCodeWrapper.java:876)
  	at jdk.compiler/com.sun.tools.javac.api.MultiTaskListener.finished(MultiTaskListener.java:133)
  	at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1443)

[cpovirk]

Yes, this goes away with the fix for #159. (And I don't see any other crashes, though again, I don't think the checker was even able to attempt to build all the targets we use it on yet.) I'll close this bug in favor of that one.

[cpovirk]

(I have now gotten myself confused about exactly which configurations I've tested. Notably, I may have used the old jspecify/checker-framework fork in one or both rounds of internal testing instead of using eisop/checker-framework? I could retrace my steps further here, but for now, I'm just going to make sure that I have (a) the latest errors and (b) a proper testing setup for the future. As best I recall, I did produce standalone reproducers for the other problems I reported, so I don't think this calls any of them into question.)

[cpovirk]

(At this point, I now think that I did get both rounds of internal testing right. I just got confused today because I thought I was retesting the late-March code (PR #165) but I saw this error from the early-February code. But in fact I was accidentally retesting the early-February code, so it makes perfect sense that I would see this early-February error.)