vfsSpec << CHILD_IS_PREFIX
    }

    static ChildMap<FileSystemNode> sortedChildren(String path1, FileSystemNode child1, String path2, FileSystemNode child2) {
        def compared = PathUtil.getPathComparator(CASE_SENSITIVE).compare(path1, path2)
        def entry1 = new ChildMap.Entry<FileSystemNode>(path1, child1)
        def entry2 = new ChildMap.Entry<FileSystemNode>(path2, child2)

    def diffListener = new SnapshotHierarchy.NodeDiffListener() {
        @Override
        void nodeRemoved(FileSystemNode node) {
        }

        @Override
        void nodeAdded(FileSystemNode node) {
        }
    }

    def "creates from a single file"() {
        def dir = tmpDir.createDir("dir")
        def child = dir.file("child").createFile()

            this.delegate = delegate;
        }

        @Override
        public void nodeRemoved(FileSystemNode node) {
            maybeLogVfsChangeMessage();
            delegate.nodeRemoved(node);
        }

        @Override
        public void nodeAdded(FileSystemNode node) {
            maybeLogVfsChangeMessage();
            delegate.nodeAdded(node);
        }