}

    @Override
    public FileTreeInternal treeOf(List<? extends FileTreeInternal> fileTrees) {
        if (fileTrees.isEmpty()) {
            return FileCollectionFactory.emptyTree();
        } else if (fileTrees.size() == 1) {
            return fileTrees.get(0);
        } else {

        }
    }

    private static void initExecutionMode(String[] args) {
        if (args.length != 1) {
            throw new IllegalArgumentException("Requires 1 param: " + Stream.of(ExecutionMode.values()).map(ExecutionMode::toString).collect(Collectors.joining("/")));
        }
        executionMode = ExecutionMode.valueOf(args[0]);

        if (displayName != null) {
            formatter.node("display name: " + displayName);
        }
        List<Object> paths = new ArrayList<>();
        value.collectSource(paths);
        if (!paths.isEmpty()) {
            formatter.node("contents");
            formatter.startChildren();
            for (Object path : paths) {
                if (path instanceof FileCollectionInternal) {

        }

        @Override
        public void conventionFromAnyFile(Provider<Object> provider) {
            convention(provider.map(value -> {
                if (value instanceof File) {
                    return fromFile((File) value);
                } else if (checkNotNull(getType()).isAssignableFrom(value.getClass())) {
                    return Cast.uncheckedNonnullCast(value);
                } else {

        Iterator<File> iterator = iterator();
        if (!iterator.hasNext()) {
            throw new IllegalStateException(String.format("Expected %s to contain exactly one file, however, it contains no files.", getDisplayName()));
        }
        File singleFile = iterator.next();
        if (iterator.hasNext()) {