code: ///////////////////////////////////////////////////////////////////////////////////////////////
  // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
  // Copyright (C) 2001-2023 the original author or authors.
  //
  // This library is free software; you can redistribute it and/or
  // modify it under the terms of the GNU Lesser General Public
  // License as published by the Free Software Foundation; either
  // version 2.1 of the License, or (at your option) any later version.
  //
  // This library is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  // Lesser General Public License for more details.
  //
  // You should have received a copy of the GNU Lesser General Public
  // License along with this library; if not, write to the Free Software
  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  ///////////////////////////////////////////////////////////////////////////////////////////////
  
  package com.puppycrawl.tools.checkstyle.internal;
  
  import static com.google.common.truth.Truth.assertWithMessage;
  
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.nio.file.Paths;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  import java.util.stream.Collectors;
  
  import org.junit.jupiter.api.Test;
  import org.w3c.dom.Document;
  import org.w3c.dom.Node;
  import org.w3c.dom.NodeList;
  
  import com.puppycrawl.tools.checkstyle.internal.utils.XmlUtil;
  import picocli.CommandLine;
  import picocli.CommandLine.Model.OptionSpec;
  
  public class CliOptionsXdocsSyncTest {
  
      @Test
      public void validateCliDocSections() throws Exception {
          final Map<String, String> cmdDesc = new HashMap<>();
  
          final NodeList sections = getSectionsFromXdoc("src/xdocs/cmdline.xml.vm");
          final Set<String> cmdOptions = getListById(sections.item(2), "CLI_Options");
          for (String option : cmdOptions) {
              final String text = option.trim().replaceAll("\\s+", " ");
              cmdDesc.put(text.substring(0, 2), text.substring(text.indexOf(" - ") + 3));
          }
  
          final Class<?> cliOptions = Class.forName("com.puppycrawl.tools.checkstyle"
                  + ".Main$CliOptions");
          final CommandLine commandLine = new CommandLine(cliOptions);
          final List<OptionSpec> optionSpecList = commandLine.getCommandSpec().options();
  
          for (OptionSpec opt : optionSpecList) {
              final String option = opt.names()[0];
              if ("-h".equals(option) || "-V".equals(option)) {
                  cmdDesc.remove(option);
                  continue;
              }
              final String descXdoc = cmdDesc.get(option);
              final String descMain = opt.description()[0];
              assertWithMessage("CLI Option: " + option + " present in "
                      + "Main.java but not documented in cmdline.xml.vm")
                      .that(descXdoc)
                      .isNotNull();
              assertWithMessage("CLI options descriptions in xdoc: "
                      + " should match that of in Main.java")
                  .that(descMain)
                  .isEqualTo(descXdoc);
              cmdDesc.remove(option);
          }
          assertWithMessage("CLI Options: %s present in cmdline.xml.vm, not documented in Main.java",
                      cmdDesc)
                  .that(cmdDesc)
                  .isEmpty();
      }
  
      @Test
      public void validateCliUsageSection() throws Exception {
          final NodeList sections = getSectionsFromXdoc("src/xdocs/cmdline.xml.vm");
          final Node usageSource = XmlUtil.getFirstChildElement(sections.item(2));
          final String usageText = XmlUtil.getFirstChildElement(usageSource).getTextContent();
  
          final Set<String> shortParamsXdoc = getParameters(usageText, "-[a-zA-CE-X]\\b");
          final Set<String> longParamsXdoc = getParameters(usageText, "-(-\\w+)+");
  
          final Class<?> cliOptions = Class.forName("com.puppycrawl.tools.checkstyle"
                  + ".Main$CliOptions");
          final CommandLine commandLine = new CommandLine(cliOptions);
          final Set<String> shortParamsMain = commandLine.getCommandSpec().options()
                          .stream()
                          .map(OptionSpec::shortestName)
                          .collect(Collectors.toSet());
          final Set<String> longParamsMain = commandLine.getCommandSpec().options()
                          .stream()
                          .map(OptionSpec::longestName)
                          .filter(names -> names.length() != 2)
                          .collect(Collectors.toSet());
  
          assertWithMessage("Short parameters in Main.java and cmdline"
                  + ".xml.vm should match")
              .that(shortParamsMain)
              .isEqualTo(shortParamsXdoc);
          assertWithMessage("Long parameters in Main.java and cmdline"
                  + ".xml.vm should match")
              .that(longParamsMain)
              .isEqualTo(longParamsXdoc);
      }
  
      private static Set<String> getParameters(String text, String regex) {
          final Set<String> result = new HashSet<>();
          final Pattern pattern = Pattern.compile(regex);
          final Matcher matcher = pattern.matcher(text);
          while (matcher.find()) {
              result.add(matcher.group());
          }
          return result;
      }
  
      private static NodeList getSectionsFromXdoc(String xdocPath) throws Exception {
          final Path path = Paths.get(xdocPath);
          final String input = Files.readString(path);
          final Document document = XmlUtil.getRawXml(path.getFileName().toString(), input, input);
          return document.getElementsByTagName("section");
      }
  
      private static Set<String> getListById(Node subSection, String id) {
          Set<String> result = null;
          final Node node = XmlUtil.findChildElementById(subSection, id);
          if (node != null) {
              result = XmlUtil.getChildrenElements(node)
                      .stream()
                      .map(Node::getTextContent)
                      .collect(Collectors.toSet());
          }
          return result;
      }
  }
  