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 org.checkstyle.suppressionxpathfilter;
  
  import java.io.File;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  
  import org.junit.jupiter.api.Test;
  
  import com.puppycrawl.tools.checkstyle.DefaultConfiguration;
  import com.puppycrawl.tools.checkstyle.checks.whitespace.EmptyLineSeparatorCheck;
  
  public class XpathRegressionEmptyLineSeparatorTest extends AbstractXpathTestSupport {
  
      @Override
      protected String getCheckName() {
          return EmptyLineSeparatorCheck.class.getSimpleName();
      }
  
      @Test
      public void testOne() throws Exception {
          final File fileToProcess = new File(
                  getPath("SuppressionXpathRegressionEmptyLineSeparator1.java")
          );
  
          final DefaultConfiguration moduleConfig =
                  createModuleConfig(EmptyLineSeparatorCheck.class);
          moduleConfig.addProperty("tokens", "PACKAGE_DEF");
  
          final String[] expectedViolation = {
              "4:1: " + getCheckMessage(EmptyLineSeparatorCheck.class,
                      EmptyLineSeparatorCheck.MSG_SHOULD_BE_SEPARATED, "package"),
          };
  
          final List<String> expectedXpathQueries = Arrays.asList(
                  "/COMPILATION_UNIT", "/COMPILATION_UNIT/PACKAGE_DEF"
          );
  
          runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
      }
  
      @Test
      public void testTwo() throws Exception {
          final File fileToProcess = new File(
                  getPath("SuppressionXpathRegressionEmptyLineSeparator2.java")
          );
  
          final DefaultConfiguration moduleConfig =
                  createModuleConfig(EmptyLineSeparatorCheck.class);
          moduleConfig.addProperty("allowMultipleEmptyLines", "false");
  
          final String[] expectedViolation = {
              "6:1: " + getCheckMessage(EmptyLineSeparatorCheck.class,
                      EmptyLineSeparatorCheck.MSG_MULTIPLE_LINES, "package"),
          };
  
          final List<String> expectedXpathQueries = Arrays.asList(
                  "/COMPILATION_UNIT", "/COMPILATION_UNIT/PACKAGE_DEF"
          );
  
          runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
      }
  
      @Test
      public void testThree() throws Exception {
          final File fileToProcess = new File(
                  getPath("SuppressionXpathRegressionEmptyLineSeparator3.java")
          );
  
          final DefaultConfiguration moduleConfig =
                  createModuleConfig(EmptyLineSeparatorCheck.class);
          moduleConfig.addProperty("tokens", "METHOD_DEF");
  
          final String[] expectedViolation = {
              "9:5: " + getCheckMessage(EmptyLineSeparatorCheck.class,
                      EmptyLineSeparatorCheck.MSG_SHOULD_BE_SEPARATED, "METHOD_DEF"),
          };
  
          final List<String> expectedXpathQueries = Arrays.asList(
                  "/COMPILATION_UNIT/CLASS_DEF"
                          + "[./IDENT[@text='SuppressionXpathRegressionEmptyLineSeparator3']]"
                          + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo1']]",
  
                  "/COMPILATION_UNIT/CLASS_DEF"
                          + "[./IDENT[@text='SuppressionXpathRegressionEmptyLineSeparator3']]"
                          + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo1']]"
                          + "/MODIFIERS",
  
                  "/COMPILATION_UNIT/CLASS_DEF"
                          + "[./IDENT[@text='SuppressionXpathRegressionEmptyLineSeparator3']]"
                          + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo1']]"
                          + "/MODIFIERS/LITERAL_PUBLIC"
          );
  
          runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
      }
  
      @Test
      public void testFour() throws Exception {
          final File fileToProcess = new File(
                  getPath("SuppressionXpathRegressionEmptyLineSeparator4.java")
          );
  
          final DefaultConfiguration moduleConfig =
                  createModuleConfig(EmptyLineSeparatorCheck.class);
          moduleConfig.addProperty("allowMultipleEmptyLines", "false");
  
          final String[] expectedViolation = {
              "12:25: " + getCheckMessage(EmptyLineSeparatorCheck.class,
                      EmptyLineSeparatorCheck.MSG_MULTIPLE_LINES_AFTER, "}"),
          };
  
          final List<String> expectedXpathQueries = Collections.singletonList(
                  "/COMPILATION_UNIT/CLASS_DEF"
                          + "[./IDENT[@text='SuppressionXpathRegressionEmptyLineSeparator4']]"
                          + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo1']]/SLIST/RCURLY"
          );
  
          runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
      }
  
      @Test
      public void testFive() throws Exception {
          final File fileToProcess = new File(
                  getPath("SuppressionXpathRegressionEmptyLineSeparator5.java")
          );
  
          final DefaultConfiguration moduleConfig =
                  createModuleConfig(EmptyLineSeparatorCheck.class);
          moduleConfig.addProperty("allowMultipleEmptyLines", "false");
          moduleConfig.addProperty("allowMultipleEmptyLinesInsideClassMembers", "false");
  
          final String[] expectedViolation = {
              "14:15: " + getCheckMessage(EmptyLineSeparatorCheck.class,
                      EmptyLineSeparatorCheck.MSG_MULTIPLE_LINES_INSIDE),
          };
  
          final List<String> expectedXpathQueries = Collections.singletonList(
                  "/COMPILATION_UNIT/CLASS_DEF"
                          + "[./IDENT[@text='SuppressionXpathRegressionEmptyLineSeparator5']]"
                          + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo1']]/SLIST/LITERAL_TRY/SLIST"
                          + "/SINGLE_LINE_COMMENT/COMMENT_CONTENT[@text=' warn\\n']"
          );
  
          runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
      }
  }
  