def visitor = new TestInstanceMetadataVisitor()

        when:
        TypeMetadataWalker.instanceWalker(typeMetadataStore, TestNested.class).walk(myTask, visitor)

        then:
        visitor.roots == ["null::$myTask"] as List<String>
        visitor.nested == ["nested::null", "nestedList::null", "nestedListOfLists::null", "nestedMap::null", "nestedNamedList::null", "nestedProperty::null"] as List<String>

        declareClass(visitor, interfacesToImplement, generatedType, superclassType);
        declareStateField(visitor);
        declareTypeConverterField(visitor);
        declareManagedTypeField(visitor);
        declareCanCallSettersField(visitor);
        writeStaticConstructor(visitor, generatedType, viewClass);

        @Override
        public void visit(Visitor visitor) {
            visitor.visitArtifacts(new Artifacts() {
                @Override
                public void startFinalization(BuildOperationQueue<RunnableBuildOperation> actions, boolean requireFiles) {
                    // Nothing to do
                }

                @Override
                public void visit(ArtifactVisitor visitor) {

    private final ResolvedFileVisitor visitor;

    public ArtifactVisitorToResolvedFileVisitorAdapter(ResolvedFileVisitor visitor) {
        this.visitor = visitor;
    }

    @Override
    public FileCollectionStructureVisitor.VisitType prepareForVisit(FileCollectionInternal.Source source) {
        return visitor.prepareForVisit(source);
    }

    public void visitFile(File file) {

    @Override
    public void visit(FileVisitor visitor) {
        Spec<FileTreeElement> spec = patterns.getAsSpec();
        tree.visit(new FileVisitor() {
            @Override
            public void visitDir(FileVisitDetails dirDetails) {
                if (spec.isSatisfiedBy(dirDetails)) {
                    visitor.visitDir(dirDetails);
                }
            }

            @Override

            scanner.find('}');
            String value = scanner.region();
            visitor.onText(value);
        }

        // end of tag marker
        if (scanner.lookingAt('}')) {
            visitor.onEndJavadocTag(tagName);
            scanner.next();
        }
    }

    private void parseStartElement(TokenVisitor visitor) {
        // start element marker
        scanner.next();

        this(visitor, resolver, taskDependencyFactory, patternSetFactory, ProviderResolutionStrategy.REQUIRE_PRESENT, true);
    }

    public UnpackingVisitor(Consumer<FileCollectionInternal> visitor, PathToFileResolver resolver, TaskDependencyFactory taskDependencyFactory, Factory<PatternSet> patternSetFactory, ProviderResolutionStrategy providerResolutionStrategy, boolean includeBuildable) {
        this.visitor = visitor;

        then:
        1 * source1.visit(closureAsVisitor)
        1 * source2.visit(closureAsVisitor)
    }

    def visitsEachTreeWithAction() {
        final Action<FileVisitDetails> visitor = Actions.doNothing()

        when:
        tree.visit(visitor)

        then:
        1 * source1.visit(visitor)
        1 * source2.visit(visitor)
    }

                }
                visitor.endChildren();
            }
        } else if (t.getCause() != null) {
            visitor.startChildren();
            visitContextual(t.getCause(), visitor);
            visitor.endChildren();
        }
    }

    private void visitContextual(Throwable t, TreeVisitor<? super Throwable> visitor) {
        Throwable next = findNearestContextual(t);

        def visitor = new CollectingValueVisitor()
        hierarchy.visitValues("", visitor)
        return visitor.allValues
    }

    static List<Integer> getValuesFor(ValuedVfsHierarchy<Integer> hierarchy, String location) {
        def visitor = new CollectingValueVisitor()
        hierarchy.visitValues(location, visitor)
        return visitor.allValues
    }