///////////////////////////////////////////////////////////////////////////////////////////////
   // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
   // Copyright (C) 2001-2026 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;
  
  import static com.google.common.truth.Truth.assertWithMessage;
  
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.LineNumberReader;
  import java.nio.charset.StandardCharsets;
  import java.nio.file.Path;
  import java.text.MessageFormat;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  import java.util.ResourceBundle;
  import java.util.stream.Collectors;
  
  import com.google.common.collect.ImmutableMap;
  import com.google.common.collect.Maps;
  import com.puppycrawl.tools.checkstyle.LocalizedMessage.Utf8Control;
  import com.puppycrawl.tools.checkstyle.api.AuditListener;
  import com.puppycrawl.tools.checkstyle.api.Configuration;
  import com.puppycrawl.tools.checkstyle.api.DetailAST;
  import com.puppycrawl.tools.checkstyle.bdd.InlineConfigParser;
  import com.puppycrawl.tools.checkstyle.bdd.TestInputConfiguration;
  import com.puppycrawl.tools.checkstyle.bdd.TestInputViolation;
  import com.puppycrawl.tools.checkstyle.internal.utils.BriefUtLogger;
  import com.puppycrawl.tools.checkstyle.internal.utils.TestUtil;
  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
  import com.puppycrawl.tools.checkstyle.utils.ModuleReflectionUtil;
  import com.puppycrawl.tools.checkstyle.xpath.RootNode;
  
  public abstract class AbstractModuleTestSupport extends AbstractPathTestSupport {
  
      protected static final String ROOT_MODULE_NAME = Checker.class.getSimpleName();
  
      private final ByteArrayOutputStream stream = new ByteArrayOutputStream();
  
      /**
       * Returns log stream.
       *
       * @return stream with log
       */
      protected final ByteArrayOutputStream getStream() {
          return stream;
      }
  
      /**
       * Returns test logger.
       *
       * @return logger for tests
       */
      protected final BriefUtLogger getBriefUtLogger() {
          return new BriefUtLogger(stream);
      }
  
      /**
       * Creates a default module configuration {@link DefaultConfiguration} for a given object
       * of type {@link Class}.
       *
       * @param clazz a {@link Class} type object.
       * @return default module configuration for the given {@link Class} instance.
       */
      protected static DefaultConfiguration createModuleConfig(Class<?> clazz) {
          return new DefaultConfiguration(clazz.getName());
      }
  
      /**
       * Creates {@link Checker} instance based on the given {@link Configuration} instance.
       *
       * @param moduleConfig {@link Configuration} instance.
       * @return {@link Checker} instance based on the given {@link Configuration} instance.
       * @throws Exception if an exception occurs during checker configuration.
       */
     protected final Checker createChecker(Configuration moduleConfig)
             throws Exception {
         final String moduleName = moduleConfig.getName();
         final Checker checker = new Checker();
         checker.setModuleClassLoader(Thread.currentThread().getContextClassLoader());
 
         if (ROOT_MODULE_NAME.equals(moduleName)) {
             checker.configure(moduleConfig);
         }
         else {
             configureChecker(checker, moduleConfig);
         }
 
         checker.addListener(getBriefUtLogger());
         return checker;
     }
 
     /**
      * Configures the {@code checker} instance with {@code moduleConfig}.
      *
      * @param checker {@link Checker} instance.
      * @param moduleConfig {@link Configuration} instance.
      * @throws Exception if an exception occurs during configuration.
      */
     protected void configureChecker(Checker checker, Configuration moduleConfig) throws Exception {
         final Class<?> moduleClass = Class.forName(moduleConfig.getName());
 
         final Configuration config;
         if (ModuleReflectionUtil.isCheckstyleTreeWalkerCheck(moduleClass)
                 || ModuleReflectionUtil.isTreeWalkerFilterModule(moduleClass)) {
             config = createTreeWalkerConfig(moduleConfig);
         }
         else {
             config = createRootConfig(moduleConfig);
         }
         checker.configure(config);
     }
 
     /**
      * Creates {@link DefaultConfiguration} for the {@link TreeWalker}
      * based on the given {@link Configuration} instance.
      *
      * @param config {@link Configuration} instance.
      * @return {@link DefaultConfiguration} for the {@link TreeWalker}
      *     based on the given {@link Configuration} instance.
      */
     protected static DefaultConfiguration createTreeWalkerConfig(Configuration config) {
         final DefaultConfiguration rootConfig =
                 new DefaultConfiguration(ROOT_MODULE_NAME);
         final DefaultConfiguration twConf = createModuleConfig(TreeWalker.class);
         // make sure that the tests always run with this charset
         rootConfig.addProperty("charset", StandardCharsets.UTF_8.name());
         rootConfig.addChild(twConf);
         twConf.addChild(config);
         return rootConfig;
     }
 
     /**
      * Creates {@link DefaultConfiguration} for the given {@link Configuration} instance.
      *
      * @param config {@link Configuration} instance.
      * @return {@link DefaultConfiguration} for the given {@link Configuration} instance.
      */
     protected static DefaultConfiguration createRootConfig(Configuration config) {
         final DefaultConfiguration rootConfig = new DefaultConfiguration(ROOT_MODULE_NAME);
         if (config != null) {
             rootConfig.addChild(config);
         }
         return rootConfig;
     }
 
     /**
      * Returns canonical path for the file with the given file name.
      * The path is formed base on the non-compilable resources location.
      *
      * @param filename file name.
      * @return canonical path for the file with the given file name.
      * @throws IOException if I/O exception occurs while forming the path.
      */
     protected final String getNonCompilablePath(String filename) throws IOException {
         return new File("src/" + getResourceLocation()
                 + "/resources-noncompilable/" + getPackageLocation() + "/"
                 + filename).getCanonicalPath();
     }
 
     /**
      * Creates a RootNode for non-compilable test files.
      *
      * @param fileName name of the test file
      * @return RootNode for the parsed AST
      * @throws Exception if file parsing fails
      */
     protected RootNode getRootNodeForNonCompilable(String fileName) throws Exception {
         final File file = new File(getNonCompilablePath(fileName));
         final DetailAST rootAst = JavaParser.parseFile(file, JavaParser.Options.WITHOUT_COMMENTS);
         return new RootNode(rootAst);
     }
 
     /**
      * Returns URI-representation of the path for the given file name.
      * The path is formed base on the root location.
      *
      * @param filename file name.
      * @return URI-representation of the path for the file with the given file name.
      */
     protected final String getUriString(String filename) {
         return new File("src/test/resources/" + getPackageLocation() + "/" + filename).toURI()
                 .toString();
     }
 
     /**
      * Performs verification of the file with the given file path using specified configuration
      * and the array of expected messages. Also performs verification of the config with filters
      * specified in the input file.
      *
      * @param filePath file path to verify.
      * @param expectedUnfiltered an array of expected unfiltered config.
      * @param expectedFiltered an array of expected config with filters.
      * @throws Exception if exception occurs during verification process.
      */
     protected final void verifyFilterWithInlineConfigParser(String filePath,
                                                             String[] expectedUnfiltered,
                                                             String... expectedFiltered)
             throws Exception {
         final TestInputConfiguration testInputConfiguration =
                 InlineConfigParser.parseWithFilteredViolations(filePath);
         final DefaultConfiguration configWithoutFilters =
                 testInputConfiguration.createConfigurationWithoutFilters();
         final List<TestInputViolation> violationsWithoutFilters =
                 new ArrayList<>(testInputConfiguration.getViolations());
         violationsWithoutFilters.addAll(testInputConfiguration.getFilteredViolations());
         Collections.sort(violationsWithoutFilters);
         verifyViolations(configWithoutFilters, filePath, violationsWithoutFilters);
         verify(configWithoutFilters, filePath, expectedUnfiltered);
         final DefaultConfiguration configWithFilters =
                 testInputConfiguration.createConfiguration();
         verifyViolations(configWithFilters, filePath, testInputConfiguration.getViolations());
         verify(configWithFilters, filePath, expectedFiltered);
     }
 
     /**
      * Performs verification of the file with given file path using configurations parsed from
      * xml header of the file and the array expected messages. Also performs verification of
      * the config specified in input file.
      *
      * @param filePath file path to verify
      * @param expected an array of expected messages
      * @throws Exception if exception occurs
      */
     protected final void verifyWithInlineXmlConfig(String filePath, String... expected)
             throws Exception {
         final TestInputConfiguration testInputConfiguration =
                 InlineConfigParser.parseWithXmlHeader(filePath);
         final Configuration xmlConfig =
                 testInputConfiguration.getXmlConfiguration();
         verifyViolations(xmlConfig, filePath, testInputConfiguration.getViolations());
         verify(xmlConfig, filePath, expected);
     }
 
     /**
      * Performs verification of the file with the given file path using configuration,
      * loaded from an external XML resource and the array of expected messages.
      *
      * @param configPath path to the XML configuration resource.
      * @param filePath file path to verify.
      * @param expected an array of expected messages.
      * @throws Exception if exception occurs during verification process.
      */
     protected void verifyWithExternalXmlConfig(
             String configPath,
             String filePath,
             String... expected)
             throws Exception {
         final Configuration config =
                 ConfigurationLoader.loadConfiguration(
                         configPath,
                         new PropertiesExpander(System.getProperties()),
                         ConfigurationLoader.IgnoredModulesOptions.EXECUTE);
         verify(config, filePath, expected);
     }
 
     /**
      * Performs verification of the file with the given file path using specified configuration
      * and the array expected messages. Also performs verification of the config specified in
      * input file.
      *
      * @param filePath file path to verify.
      * @param expected an array of expected messages.
      * @throws Exception if exception occurs during verification process.
      */
     protected final void verifyWithInlineConfigParser(String filePath, String... expected)
             throws Exception {
         final TestInputConfiguration testInputConfiguration =
                 InlineConfigParser.parse(filePath);
         final DefaultConfiguration parsedConfig =
                 testInputConfiguration.createConfiguration();
         final List<String> actualViolations = getActualViolationsForFile(parsedConfig, filePath);
         verifyViolations(filePath, testInputConfiguration.getViolations(), actualViolations);
         assertWithMessage("Violations for %s differ.", filePath)
             .that(actualViolations)
             .containsExactlyElementsIn(expected);
     }
 
     /**
      * Performs verification of two files with their given file paths using specified
      * configuration of one file only. Also performs verification of the config specified
      * in the input file. This method needs to be implemented when two given files need to be
      * checked through a single check only.
      *
      * @param filePath1 file path of first file to verify
      * @param filePath2 file path of second file to verify
      * @param expected an array of expected messages
      * @throws Exception if exception occurs during verification process
      */
     protected final void verifyWithInlineConfigParser(String filePath1,
                                                       String filePath2,
                                                       String... expected)
             throws Exception {
         final TestInputConfiguration testInputConfiguration1 =
                 InlineConfigParser.parse(filePath1);
         final DefaultConfiguration parsedConfig =
                 testInputConfiguration1.createConfiguration();
         final TestInputConfiguration testInputConfiguration2 =
                 InlineConfigParser.parse(filePath2);
         verifyViolations(parsedConfig, filePath1, testInputConfiguration1.getViolations());
         verifyViolations(parsedConfig, filePath2, testInputConfiguration2.getViolations());
         verify(createChecker(parsedConfig),
                 new File[] {new File(filePath1), new File(filePath2)},
                 filePath1,
                 expected);
     }
 
     /**
      * Performs verification of two files with their given file paths.
      * using specified configuration of one file only. Also performs
      * verification of the config specified in the input file. This method
      * needs to be implemented when two given files need to be
      * checked through a single check only.
      *
      * @param filePath1 file path of first file to verify
      * @param filePath2 file path of first file to verify
      * @param expectedFromFile1 list of expected message
      * @param expectedFromFile2 list of expected message
      * @throws Exception if exception occurs during verification process
      */
     protected final void verifyWithInlineConfigParser(String filePath1,
                                                       String filePath2,
                                                       List<String> expectedFromFile1,
                                                       List<String> expectedFromFile2)
             throws Exception {
         final TestInputConfiguration testInputConfiguration = InlineConfigParser.parse(filePath1);
         final DefaultConfiguration parsedConfig = testInputConfiguration.createConfiguration();
         final TestInputConfiguration testInputConfiguration2 = InlineConfigParser.parse(filePath2);
         final DefaultConfiguration parsedConfig2 = testInputConfiguration.createConfiguration();
         final File[] inputs = {new File(filePath1), new File(filePath2)};
         verifyViolations(parsedConfig, filePath1, testInputConfiguration.getViolations());
         verifyViolations(parsedConfig2, filePath2, testInputConfiguration2.getViolations());
         verify(createChecker(parsedConfig), inputs, ImmutableMap.of(
             filePath1, expectedFromFile1,
             filePath2, expectedFromFile2));
     }
 
     /**
      * Verifies the target file against the configuration specified in a separate configuration
      * file.
      * This method is intended for use cases when the configuration is stored in one file and the
      * content to verify is stored in another file.
      *
      * @param fileWithConfig file path of the configuration file
      * @param targetFile file path of the target file to be verified
      * @param expected an array of expected messages
      * @throws Exception if an exception occurs during verification process
      */
     protected final void verifyWithInlineConfigParserSeparateConfigAndTarget(String fileWithConfig,
                                                                              String targetFile,
                                                                              String... expected)
             throws Exception {
         final TestInputConfiguration testInputConfiguration1 =
                 InlineConfigParser.parse(fileWithConfig);
         final DefaultConfiguration parsedConfig =
                 testInputConfiguration1.createConfiguration();
         final List<TestInputViolation> inputViolations =
                 InlineConfigParser.getViolationsFromInputFile(targetFile);
         final List<String> actualViolations = getActualViolationsForFile(parsedConfig, targetFile);
         verifyViolations(targetFile, inputViolations, actualViolations);
         assertWithMessage("Violations for %s differ.", targetFile)
                 .that(actualViolations)
                 .containsExactlyElementsIn(expected);
     }
 
     /**
      * Performs verification of the file with the given file path using specified configuration
      * and the array of expected messages. Also performs verification of the config with filters
      * specified in the input file.
      *
      * @param fileWithConfig file path of the configuration file.
      * @param targetFilePath file path of the target file to be verified.
      * @param expectedUnfiltered an array of expected unfiltered config.
      * @param expectedFiltered an array of expected config with filters.
      * @throws Exception if exception occurs during verification process.
      */
     protected final void verifyFilterWithInlineConfigParserSeparateConfigAndTarget(
             String fileWithConfig,
             String targetFilePath,
             String[] expectedUnfiltered,
             String... expectedFiltered)
             throws Exception {
         final TestInputConfiguration testInputConfiguration =
                 InlineConfigParser.parseWithFilteredViolations(fileWithConfig);
         final DefaultConfiguration configWithoutFilters =
                 testInputConfiguration.createConfigurationWithoutFilters();
         final List<TestInputViolation> violationsWithoutFilters = new ArrayList<>(
                 InlineConfigParser.getFilteredViolationsFromInputFile(targetFilePath));
         violationsWithoutFilters.addAll(
                 InlineConfigParser.getViolationsFromInputFile(targetFilePath));
         Collections.sort(violationsWithoutFilters);
         verifyViolations(configWithoutFilters, targetFilePath, violationsWithoutFilters);
         verify(configWithoutFilters, targetFilePath, expectedUnfiltered);
         final DefaultConfiguration configWithFilters =
                 testInputConfiguration.createConfiguration();
         final List<TestInputViolation> violationsWithFilters =
                 InlineConfigParser.getViolationsFromInputFile(targetFilePath);
         verifyViolations(configWithFilters, targetFilePath, violationsWithFilters);
         verify(configWithFilters, targetFilePath, expectedFiltered);
     }
 
     /**
      * Performs verification of the file with the given file path using specified configuration
      * and the array expected messages. Also performs verification of the config specified in
      * input file
      *
      * @param filePath file path to verify.
      * @param expected an array of expected messages.
      * @throws Exception if exception occurs during verification process.
      */
     protected void verifyWithInlineConfigParserTwice(String filePath, String... expected)
             throws Exception {
         final TestInputConfiguration testInputConfiguration =
                 InlineConfigParser.parse(filePath);
         final DefaultConfiguration parsedConfig =
                 testInputConfiguration.createConfiguration();
         verifyViolations(parsedConfig, filePath, testInputConfiguration.getViolations());
         verify(parsedConfig, filePath, expected);
     }
 
     /**
      * Verifies logger output using the inline configuration parser.
      * Expects an input file with configuration and violations, and a report file with expected
      * output.
      *
      * @param inputFile path to the file with configuration and violations
      * @param expectedReportFile path to the expected logger report file
      * @param logger logger to test
      * @param outputStream output stream where the logger writes its actual output
      * @throws Exception if an exception occurs during verification
      */
     protected void verifyWithInlineConfigParserAndLogger(String inputFile,
                                                          String expectedReportFile,
                                                          AuditListener logger,
                                                          ByteArrayOutputStream outputStream)
             throws Exception {
         final TestInputConfiguration testInputConfiguration =
                 InlineConfigParser.parse(inputFile);
         final DefaultConfiguration parsedConfig =
                 testInputConfiguration.createConfiguration();
         final List<File> filesToCheck = Collections.singletonList(new File(inputFile));
         final String basePath = Path.of("").toAbsolutePath().toString();
 
         final Checker checker = createChecker(parsedConfig);
         checker.setBasedir(basePath);
         checker.addListener(logger);
         checker.process(filesToCheck);
 
         verifyContent(expectedReportFile, outputStream);
     }
 
     /**
      * Verifies logger output using the inline configuration parser for default logger.
      * Expects an input file with configuration and violations, and expected output file.
      * Uses full Checker configuration.
      *
      * @param inputFile path to the file with configuration and violations
      * @param expectedOutputFile path to the expected info stream output file
      * @param logger logger to test
      * @param outputStream where the logger writes its actual info stream output
      * @throws Exception if an exception occurs during verification
      */
     protected final void verifyWithInlineConfigParserAndDefaultLogger(String inputFile,
                                                               String expectedOutputFile,
                                                               AuditListener logger,
                                                               ByteArrayOutputStream outputStream)
             throws Exception {
         final TestInputConfiguration testInputConfiguration =
                 InlineConfigParser.parseWithXmlHeader(inputFile);
         final Configuration parsedConfig =
                 testInputConfiguration.getXmlConfiguration();
         final List<File> filesToCheck = Collections.singletonList(new File(inputFile));
         final String basePath = Path.of("").toAbsolutePath().toString();
 
         final Checker checker = createChecker(parsedConfig);
         checker.setBasedir(basePath);
         checker.addListener(logger);
         checker.process(filesToCheck);
 
         verifyCleanedMessageContent(expectedOutputFile, outputStream, basePath);
     }
 
     /**
      * Verifies logger output using the inline configuration parser for default logger.
      * Expects an input file with configuration and violations, and separate expected output files
      * for info and error streams.
      * Uses full Checker configuration.
      *
      * @param inputFile path to the file with configuration and violations
      * @param expectedInfoFile path to the expected info stream output file
      * @param expectedErrorFile path to the expected error stream output file
      * @param logger logger to test
      * @param infoStream where the logger writes its actual info stream output
      * @param errorStream where the logger writes its actual error stream output
      * @throws Exception if an exception occurs during verification
      * @noinspection MethodWithTooManyParameters
      * @noinspectionreason MethodWithTooManyParameters - Method requires a lot of parameters to
      *                     verify the default logger output.
      */
     protected final void verifyWithInlineConfigParserAndDefaultLogger(String inputFile,
                                                          String expectedInfoFile,
                                                          String expectedErrorFile,
                                                          AuditListener logger,
                                                          ByteArrayOutputStream infoStream,
                                                          ByteArrayOutputStream errorStream)
             throws Exception {
         final TestInputConfiguration testInputConfiguration =
                 InlineConfigParser.parseWithXmlHeader(inputFile);
         final Configuration parsedConfig =
                 testInputConfiguration.getXmlConfiguration();
         final List<File> filesToCheck = Collections.singletonList(new File(inputFile));
         final String basePath = Path.of("").toAbsolutePath().toString();
 
         final Checker checker = createChecker(parsedConfig);
         checker.setBasedir(basePath);
         checker.addListener(logger);
         checker.process(filesToCheck);
 
         verifyContent(expectedInfoFile, infoStream);
         verifyCleanedMessageContent(expectedErrorFile, errorStream, basePath);
     }
 
     /**
      * Performs verification of the file with the given file name. Uses specified configuration.
      * Expected messages are represented by the array of strings.
      * This implementation uses overloaded
      * {@link AbstractModuleTestSupport#verify(Checker, File[], String, String...)} method inside.
      *
      * @param config configuration.
      * @param fileName file name to verify.
      * @param expected an array of expected messages.
      * @throws Exception if exception occurs during verification process.
      */
     protected final void verify(Configuration config, String fileName, String... expected)
             throws Exception {
         verify(createChecker(config), fileName, fileName, expected);
     }
 
     /**
      * Performs verification of the file with the given file name.
      * Uses provided {@link Checker} instance.
      * Expected messages are represented by the array of strings.
      * This implementation uses overloaded
      * {@link AbstractModuleTestSupport#verify(Checker, String, String, String...)} method inside.
      *
      * @param checker {@link Checker} instance.
      * @param fileName file name to verify.
      * @param expected an array of expected messages.
      * @throws Exception if exception occurs during verification process.
      */
     protected void verify(Checker checker, String fileName, String... expected)
             throws Exception {
         verify(checker, fileName, fileName, expected);
     }
 
     /**
      * Performs verification of the file with the given file name.
      * Uses provided {@link Checker} instance.
      * Expected messages are represented by the array of strings.
      * This implementation uses overloaded
      * {@link AbstractModuleTestSupport#verify(Checker, File[], String, String...)} method inside.
      *
      * @param checker {@link Checker} instance.
      * @param processedFilename file name to verify.
      * @param messageFileName message file name.
      * @param expected an array of expected messages.
      * @throws Exception if exception occurs during verification process.
      */
     protected final void verify(Checker checker,
                           String processedFilename,
                           String messageFileName,
                           String... expected)
             throws Exception {
         verify(checker,
                 new File[] {new File(processedFilename)},
                 messageFileName, expected);
     }
 
     /**
      *  Performs verification of the given files against the array of
      *  expected messages using the provided {@link Checker} instance.
      *
      *  @param checker {@link Checker} instance.
      *  @param processedFiles list of files to verify.
      *  @param messageFileName message file name.
      *  @param expected an array of expected messages.
      *  @throws Exception if exception occurs during verification process.
      */
     protected void verify(Checker checker,
                           File[] processedFiles,
                           String messageFileName,
                           String... expected)
             throws Exception {
         final Map<String, List<String>> expectedViolations = new HashMap<>();
         expectedViolations.put(messageFileName, Arrays.asList(expected));
         verify(checker, processedFiles, expectedViolations);
     }
 
     /**
      * Performs verification of the given files.
      *
      * @param checker {@link Checker} instance
      * @param processedFiles files to process.
      * @param expectedViolations a map of expected violations per files.
      * @throws Exception if exception occurs during verification process.
      */
     protected final void verify(Checker checker,
                           File[] processedFiles,
                           Map<String, List<String>> expectedViolations)
             throws Exception {
         stream.flush();
         stream.reset();
         final List<File> theFiles = new ArrayList<>();
         Collections.addAll(theFiles, processedFiles);
         checker.process(theFiles);
 
         // process each of the lines
         final Map<String, List<String>> actualViolations = getActualViolations();
         final Map<String, List<String>> realExpectedViolations =
                 Maps.filterValues(expectedViolations, input -> !input.isEmpty());
 
         assertWithMessage("Files with expected violations and actual violations differ.")
             .that(actualViolations.keySet())
             .isEqualTo(realExpectedViolations.keySet());
 
         realExpectedViolations.forEach((fileName, violationList) -> {
             assertWithMessage("Violations for %s differ.", fileName)
                 .that(actualViolations.get(fileName))
                 .containsExactlyElementsIn(violationList);
         });
 
         checker.destroy();
     }
 
     /**
      * Runs 'verifyWithInlineConfigParser' with limited stack size and time duration.
      *
      * @param fileName file name to verify.
      * @param expected an array of expected messages.
      * @throws Exception if exception occurs during verification process.
      */
     protected final void verifyWithLimitedResources(String fileName, String... expected)
             throws Exception {
         TestUtil.getResultWithLimitedResources(() -> {
             verifyWithInlineConfigParser(fileName, expected);
             return null;
         });
     }
 
     /**
      * Executes given config on a list of files only. Does not verify violations.
      *
      * @param config check configuration
      * @param filenames names of files to process
      * @throws Exception if there is a problem during checker configuration
      */
     protected final void execute(Configuration config, String... filenames) throws Exception {
         final Checker checker = createChecker(config);
         final List<File> files = Arrays.stream(filenames)
                 .map(File::new)
                 .toList();
         checker.process(files);
         checker.destroy();
     }
 
     /**
      * Executes given config on a list of files only. Does not verify violations.
      *
      * @param checker check configuration
      * @param filenames names of files to process
      * @throws Exception if there is a problem during checker configuration
      */
     protected static void execute(Checker checker, String... filenames) throws Exception {
         final List<File> files = Arrays.stream(filenames)
                 .map(File::new)
                 .toList();
         checker.process(files);
         checker.destroy();
     }
 
     /**
      * Performs verification of violation lines.
      *
      * @param config parsed config.
      * @param file file path.
      * @param testInputViolations List of TestInputViolation objects.
      * @throws Exception if exception occurs during verification process.
      */
     private void verifyViolations(Configuration config,
                                   String file,
                                   List<TestInputViolation> testInputViolations)
             throws Exception {
         final List<String> actualViolations = getActualViolationsForFile(config, file);
         final List<Integer> actualViolationLines = actualViolations.stream()
                 .map(violation -> violation.substring(0, violation.indexOf(':')))
                 .map(Integer::valueOf)
                 .toList();
         final List<Integer> expectedViolationLines = testInputViolations.stream()
                 .map(TestInputViolation::getLineNo)
                 .toList();
         assertWithMessage("Violation lines for %s differ.", file)
                 .that(actualViolationLines)
                 .isEqualTo(expectedViolationLines);
         for (int index = 0; index < actualViolations.size(); index++) {
             assertWithMessage("Actual and expected violations differ.")
                     .that(actualViolations.get(index))
                     .matches(testInputViolations.get(index).toRegex());
         }
     }
 
     /**
      * Performs verification of violation lines.
      *
      * @param file file path.
      * @param testInputViolations List of TestInputViolation objects.
      * @param actualViolations for a file
      */
     private static void verifyViolations(String file,
                                   List<TestInputViolation> testInputViolations,
                                   List<String> actualViolations) {
         final List<Integer> actualViolationLines = actualViolations.stream()
                 .map(violation -> violation.substring(0, violation.indexOf(':')))
                 .map(Integer::valueOf)
                 .toList();
         final List<Integer> expectedViolationLines = testInputViolations.stream()
                 .map(TestInputViolation::getLineNo)
                 .toList();
         assertWithMessage("Violation lines for %s differ.", file)
                 .that(actualViolationLines)
                 .isEqualTo(expectedViolationLines);
         for (int index = 0; index < actualViolations.size(); index++) {
             assertWithMessage("Actual and expected violations differ.")
                     .that(actualViolations.get(index))
                     .matches(testInputViolations.get(index).toRegex());
         }
     }
 
     /**
      * Verifies that the logger's actual output matches the expected report file.
      *
      * @param expectedOutputFile path to the expected logger report file
      * @param outputStream output stream containing the actual logger output
      * @throws IOException if an exception occurs while reading the file
      */
     private static void verifyContent(
             String expectedOutputFile,
             ByteArrayOutputStream outputStream) throws IOException {
         final String expectedContent = readFile(expectedOutputFile);
         final String actualContent =
                 toLfLineEnding(outputStream.toString(StandardCharsets.UTF_8));
         assertWithMessage("Content should match")
                 .that(actualContent)
                 .isEqualTo(expectedContent);
     }
 
     /**
      * Verifies that the logger output matches the expected report file content,
      * keeping only severity-tagged lines (e.g. [ERROR], [WARN], [INFO]) or lines containing
      * "Starting audit..." or "Audit done".
      *
      * <p>
      * This method strips:
      * <ul>
      *   <li>any stack trace lines from exception outputs (i.e. lines not starting with a severity
      *   tag),</li>
      *   <li>any absolute {@code basePath} prefixes in the message content.</li>
      * </ul>
      * The result is compared with expected output that includes only severity-tagged lines.
      *
      * @param expectedOutputFile path to a file that contains the expected first line
      * @param outputStream output stream containing the actual logger output
      * @param basePath absolute path prefix to strip before comparison
      * @throws IOException if an exception occurs while reading the file
      */
     private static void verifyCleanedMessageContent(
             String expectedOutputFile,
             ByteArrayOutputStream outputStream,
             String basePath) throws IOException {
         final String expectedContent = readFile(expectedOutputFile);
         final String rawActualContent =
                 toLfLineEnding(outputStream.toString(StandardCharsets.UTF_8));
 
         final String cleanedActualContent = rawActualContent.lines()
                 .filter(line -> {
                     return line.startsWith("[")
                             || line.contains("Starting audit...")
                             || line.contains("Audit done.");
                 })
                 .map(line -> line.replace(basePath, ""))
                 .map(line -> line.replace('\\', '/'))
                 .collect(Collectors.joining("\n", "", "\n"));
 
         assertWithMessage("Content should match")
                 .that(cleanedActualContent)
                 .isEqualTo(expectedContent);
     }
 
     /**
      * Tests the file with the check config.
      *
      * @param config check configuration.
      * @param file input file path.
      * @return list of actual violations.
      * @throws Exception if exception occurs during verification process.
      */
     private List<String> getActualViolationsForFile(Configuration config,
                                                     String file) throws Exception {
         stream.flush();
         stream.reset();
         final List<File> files = Collections.singletonList(new File(file));
         final Checker checker = createChecker(config);
         checker.process(files);
         final Map<String, List<String>> actualViolations =
                 getActualViolations();
         checker.destroy();
         return actualViolations.getOrDefault(file, new ArrayList<>());
     }
 
     /**
      * Returns the actual violations for each file that has been checked against {@link Checker}.
      * Each file is mapped to their corresponding violation messages. Reads input stream for these
      * messages using instance of {@link InputStreamReader}.
      *
      * @return a {@link Map} object containing file names and the corresponding violation messages.
      * @throws IOException exception can occur when reading input stream.
      */
     private Map<String, List<String>> getActualViolations() throws IOException {
         // process each of the lines
         try (ByteArrayInputStream inputStream =
                 new ByteArrayInputStream(stream.toByteArray());
             LineNumberReader lnr = new LineNumberReader(
                 new InputStreamReader(inputStream, StandardCharsets.UTF_8))) {
             final Map<String, List<String>> actualViolations = new HashMap<>();
             for (String line = lnr.readLine(); line != null;
                  line = lnr.readLine()) {
                 if ("Audit done.".equals(line) || line.contains("at com")) {
                     break;
                 }
                 // have at least 2 characters before the splitting colon,
                 // to not split after the drive letter on Windows
                 final String[] actualViolation = line.split("(?<=.{2}):", 2);
                 final String actualViolationFileName = actualViolation[0];
                 final String actualViolationMessage = actualViolation[1];
 
                 actualViolations
                         .computeIfAbsent(actualViolationFileName, key -> new ArrayList<>())
                         .add(actualViolationMessage);
             }
 
             return actualViolations;
         }
     }
 
     /**
      * Gets the check message 'as is' from appropriate 'messages.properties'
      * file.
      *
      * @param messageKey the key of message in 'messages.properties' file.
      * @param arguments  the arguments of message in 'messages.properties' file.
      * @return The message of the check with the arguments applied.
      */
     protected final String getCheckMessage(String messageKey, Object... arguments) {
         return internalGetCheckMessage(getMessageBundle(), messageKey, arguments);
     }
 
     /**
      * Gets the check message 'as is' from appropriate 'messages.properties'
      * file.
      *
      * @param clazz the related check class.
      * @param messageKey the key of message in 'messages.properties' file.
      * @param arguments the arguments of message in 'messages.properties' file.
      * @return The message of the check with the arguments applied.
      */
     protected static String getCheckMessage(
             Class<?> clazz, String messageKey, Object... arguments) {
         return internalGetCheckMessage(getMessageBundle(clazz.getName()), messageKey, arguments);
     }
 
     /**
      * Gets the check message 'as is' from appropriate 'messages.properties'
      * file.
      *
      * @param messageBundle the bundle name.
      * @param messageKey the key of message in 'messages.properties' file.
      * @param arguments the arguments of message in 'messages.properties' file.
      * @return The message of the check with the arguments applied.
      */
     private static String internalGetCheckMessage(
             String messageBundle, String messageKey, Object... arguments) {
         final ResourceBundle resourceBundle = ResourceBundle.getBundle(
                 messageBundle,
                 Locale.ROOT,
                 Thread.currentThread().getContextClassLoader(),
                 new Utf8Control());
         final String pattern = resourceBundle.getString(messageKey);
         final MessageFormat formatter = new MessageFormat(pattern, Locale.ROOT);
         return formatter.format(arguments);
     }
 
     /**
      * Returns message bundle for a class specified by its class name.
      *
      * @return a string of message bundles for the class using class name.
      */
     private String getMessageBundle() {
         final String className = getClass().getName();
         return getMessageBundle(className);
     }
 
     /**
      * Returns message bundles for a class by providing class name.
      *
      * @param className name of the class.
      * @return message bundles containing package name.
      */
     private static String getMessageBundle(String className) {
         final String messageBundle;
         final String messages = "messages";
         final int endIndex = className.lastIndexOf('.');
         final Map<String, String> messageBundleMappings = new HashMap<>();
         messageBundleMappings.put("SeverityMatchFilterExamplesTest",
                 "com.puppycrawl.tools.checkstyle.checks.naming.messages");
 
         if (endIndex < 0) {
             messageBundle = messages;
         }
         else {
             final String packageName = className.substring(0, endIndex);
             if ("com.puppycrawl.tools.checkstyle.filters".equals(packageName)) {
                 messageBundle = messageBundleMappings.get(className.substring(endIndex + 1));
             }
             else {
                 messageBundle = packageName + "." + messages;
             }
         }
         return messageBundle;
     }
 
     /**
      * Remove suppressed violation messages from actual violation messages.
      *
      * @param actualViolations actual violation messages
      * @param suppressedViolations suppressed violation messages
      * @return an array of actual violation messages minus suppressed violation messages
      */
     protected static String[] removeSuppressed(String[] actualViolations,
                                                String... suppressedViolations) {
         final List<String> actualViolationsList =
             Arrays.stream(actualViolations).collect(Collectors.toCollection(ArrayList::new));
         actualViolationsList.removeAll(Arrays.asList(suppressedViolations));
         return actualViolationsList.toArray(CommonUtil.EMPTY_STRING_ARRAY);
     }
 
 }