目录比较在Dart中不起作用？

import 'dart:io';

void main() {
  final dir1 = Directory('path/to/directory1');
  final dir2 = Directory('path/to/directory2');

  if (compareDirectories(dir1, dir2)) {
    print('Directories are the same.');
  } else {
    print('Directories are different.');
  }
}

bool compareDirectories(Directory dir1, Directory dir2) {
  final list1 = dir1.listSync(recursive: false);
  final list2 = dir2.listSync(recursive: false);

  if (list1.length != list2.length) {
    return false;
  }

  for (var i = 0; i < list1.length; i++) {
    final entity1 = list1[i];
    final entity2 = list2[i];

    if (entity1 is File && entity2 is File) {
      if (!compareFiles(entity1, entity2)) {
        return false;
      }
    } else if (entity1 is Directory && entity2 is Directory) {
      if (!compareDirectories(entity1, entity2)) {
        return false;
      }
    } else {
      return false;
    }
  }

  return true;
}

bool compareFiles(File file1, File file2) {
  // Compare file contents and attributes here
  // Return true if files are the same, false otherwise
}