Method ScratchPath

cpp/src/arrow/io/hdfs_test.cc:71–75

  }

  std::string ScratchPath(const std::string& name) {
    std::stringstream ss;
    ss << scratch_dir_ << "/" << name;
    return ss.str();
  }

  std::string HdfsAbsPath(const std::string& relpath) {
    std::stringstream ss;