我试着用Swift遍历Mac电脑上的目录树，不想像应用程序一样进入软件包。
这样遍历目录树可以很好地工作：

func traverseDirectoryTree(){
  let path = "/Users/mica/Downloads/TEST"
  let url = URL(string: path)
  
  print("try to scan Dir")
  if let enumerator = FileManager().enumerator(atPath: path) {        
    for file in enumerator {
      let fileAttributes = enumerator.fileAttributes
      
      guard let fileName = file as? String else {continue}
      print("\(fileName)")
      if let fileAttributes = fileAttributes {
        print("   Size:\(fileAttributes[.size]! )")
        print("   Tpye:\(fileAttributes[.type]! )")
        print("   Tpye:\(fileAttributes[.referenceCount]! )")
      }
      print("")
    }
  } else {
    print("creating enumerator failed")
  }
}

尝试排除软件包不会返回任何结果，也不会出现错误：

func traverseDirectoryTree(){
  let path = "/Users/mica/Downloads/TEST"
  //let url = URL(string: path)
  let url = URL(filePath: path)
  
  print("try to scan Dir")
//  if let enumerator = FileManager().enumerator(atPath: path) {

  if let enumerator = FileManager().enumerator( at: url!,
                                                includingPropertiesForKeys: [.nameKey, .isDirectoryKey, .fileSizeKey],
                                                options: [.skipsPackageDescendants]
                                               ){

          
    for file in enumerator {
      let fileAttributes = enumerator.fileAttributes
      
      guard let fileName = file as? String else {continue}
      print("\(fileName)")
      if let fileAttributes = fileAttributes {
        print("   Size:\(fileAttributes[.size]! )")
        print("   Tpye:\(fileAttributes[.type]! )")
        print("   Tpye:\(fileAttributes[.referenceCount]! )")
      }
      print("")
    }
  } else {
    print("creating enumerator failed")
  }
}