import org.gradle.api.tasks.util.PatternFilterable;

import java.util.function.Consumer;

public interface FileTreeInternal extends FileTree, FileCollectionInternal {
    String DEFAULT_TREE_DISPLAY_NAME = "file tree";

    void visitContentsAsFileTrees(Consumer<FileTreeInternal> visitor);

    @Override
    FileTreeInternal matching(PatternFilterable patterns);

import spock.lang.Specification

import java.util.function.Consumer

@UsesNativeServices
class CompositeFileTreeTest extends Specification {
    private final FileTreeInternal source1 = Mock()
    private final FileTreeInternal source2 = Mock()
    private final Factory<PatternSet> patternSetFactory = Mock()
    private final CompositeFileTree tree = new CompositeFileTree(TestFiles.taskDependencyFactory(), patternSetFactory) {

    private final Set<FileTreeInternal> sourceTrees;
    private final String displayName;

    public UnionFileTree(TaskDependencyFactory taskDependencyFactory, FileTreeInternal... sourceTrees) {
        this(taskDependencyFactory, "file tree", Arrays.asList(sourceTrees));
    }

    public UnionFileTree(TaskDependencyFactory taskDependencyFactory, String displayName, FileTreeInternal... sourceTrees) {

    private val fileOperations: FileOperations
) : Codec<FileTreeInternal> {

    override suspend fun WriteContext.encode(value: FileTreeInternal) {
        encodePreservingIdentityOf(value) {
            write(rootSpecOf(value))
        }
    }

    override suspend fun ReadContext.decode(): FileTreeInternal? =
        decodePreservingIdentity { id ->

        }
        return this;
    }

    @Override
    public FileTreeInternal getAsFileTree() {
        return this;
    }

    @Override
    public void visitContentsAsFileTrees(Consumer<FileTreeInternal> visitor) {
        visitChildren(child -> visitor.accept((FileTreeInternal) child));
    }

    private FileTreeInternal newFilteredFileTree(Supplier<? extends PatternSet> patternSetSupplier) {

    }

    @Override
    public void visitStructure(MinimalFileTreeStructureVisitor visitor, FileTreeInternal owner) {
        tree.visitStructure(new MinimalFileTreeStructureVisitor() {
            @Override
            public void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree) {
                PatternSet intersect = patterns.intersect();

    void visitStructure(MinimalFileTreeStructureVisitor visitor, FileTreeInternal owner);

    interface MinimalFileTreeStructureVisitor {

        /**
         * Visits a file tree at a root file on the file system (potentially filtered).
         */
        void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree);

        /**

            }

            @Override
            public void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree) {
                visitor.accept(fileTree);
            }

            @Override
            public void visitFileTreeBackedByFile(File file, FileTreeInternal fileTree, FileSystemMirroringFileTree sourceTree) {
                visitor.accept(fileTree);
            }
        });
    }

import java.util.function.Consumer;

public class DefaultCompositeFileTree extends CompositeFileTree {
    private final Collection<? extends FileTreeInternal> fileTrees;

    public DefaultCompositeFileTree(TaskDependencyFactory taskDependencyFactory, Factory<PatternSet> patternSetFactory, List<? extends FileTreeInternal> fileTrees) {
        super(taskDependencyFactory, patternSetFactory);
        this.fileTrees = fileTrees;
    }

    @Override

                        @Override
                        public void visitFileTree(File root, PatternSet patterns, FileTreeInternal fileTree) {
                            collections.add(fileTree);
                        }

                        @Override
                        public void visitFileTreeBackedByFile(File file, FileTreeInternal fileTree, FileSystemMirroringFileTree sourceTree) {
                            collections.add(fileTree);