docs: private List<String> readFile(String fileName) {
          List<String> result = Lists.newArrayList();
  
          try (BufferedReader bufRead = Files.newBufferedReader(Paths.get(fileName), options.atFileCharset)) {
              String line;
              // Read through file one line at time. Print line # and line
              while ((line = bufRead.readLine()) != null) {
                  // Allow empty lines and # comments in these at files
                  if (line.length() > 0 && !line.trim().startsWith("#")) {
                      result.add(line);
                  }
              }
          } catch (IOException e) {
              throw new ParameterException("Could not read file " + fileName + ": " + e);
          }
  
          return result;
      }