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.gui;
  
  import static com.google.common.truth.Truth.assertWithMessage;
  
  import java.io.File;
  import java.util.ArrayList;
  import java.util.List;
  
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  
  import com.google.common.collect.ImmutableList;
  import com.puppycrawl.tools.checkstyle.AbstractPathTestSupport;
  import com.puppycrawl.tools.checkstyle.api.DetailAST;
  import com.puppycrawl.tools.checkstyle.api.DetailNode;
  import com.puppycrawl.tools.checkstyle.gui.MainFrameModel.ParseMode;
  
  public class CodeSelectorPresentationTest extends AbstractPathTestSupport {
  
      private MainFrameModel model;
  
      private DetailAST tree;
  
      private ImmutableList<Integer> linesToPosition;
  
      @BeforeEach
      public void loadFile() throws Exception {
          model = new MainFrameModel();
          model.setParseMode(ParseMode.JAVA_WITH_JAVADOC_AND_COMMENTS);
          model.openFile(new File(getPath("InputCodeSelectorPresentation.java")));
          tree = ((DetailAST) model.getParseTreeTableModel().getRoot())
                  .getFirstChild().getNextSibling();
          linesToPosition = ImmutableList.copyOf(convertLinesToPosition(model.getLinesToPosition()));
      }
  
      @Override
      protected String getPackageLocation() {
          return "com/puppycrawl/tools/checkstyle/gui/codeselectorpresentation";
      }
  
      /**
       * Converts lineToPosition from multicharacter to one character line separator
       * needs to support crossplatform line separators.
       *
       * @param systemLinesToPosition lines to position mapping for current system
       * @return lines to position mapping with one character line separator
       */
      private static List<Integer> convertLinesToPosition(List<Integer> systemLinesToPosition) {
          final List<Integer> convertedLinesToPosition = new ArrayList<>();
          final int lineSeparationCorrection = System.lineSeparator().length() - 1;
          convertedLinesToPosition.add(0, systemLinesToPosition.get(0));
          for (int i = 1; i < systemLinesToPosition.size(); i++) {
              convertedLinesToPosition.add(i,
                      systemLinesToPosition.get(i) - lineSeparationCorrection * (i - 1));
          }
          return convertedLinesToPosition;
      }
  
      @Test
      public void testDetailASTSelection() {
          final CodeSelectorPresentation selector = new CodeSelectorPresentation(tree,
                  linesToPosition);
          selector.findSelectionPositions();
          assertWithMessage("Invalid selection start")
                  .that(selector.getSelectionStart())
                  .isEqualTo(94);
          assertWithMessage("Invalid selection end")
                  .that(selector.getSelectionEnd())
                  .isEqualTo(279);
      }
  
      @Test
      public void testDetailASTLeafSelection() {
          final DetailAST leaf = tree.getLastChild().getFirstChild();
          final CodeSelectorPresentation selector = new CodeSelectorPresentation(leaf,
                  linesToPosition);
          selector.findSelectionPositions();
          assertWithMessage("Invalid selection start")
                  .that(selector.getSelectionStart())
                  .isEqualTo(130);
          assertWithMessage("Invalid selection end")
                  .that(selector.getSelectionEnd())
                  .isEqualTo(131);
      }
  
      @Test
      public void testDetailASTNoSelection() {
          final DetailAST leaf = tree.getFirstChild();
          final CodeSelectorPresentation selector = new CodeSelectorPresentation(leaf,
                  linesToPosition);
          selector.findSelectionPositions();
          assertWithMessage("Invalid selection start")
                  .that(selector.getSelectionStart())
                  .isEqualTo(94);
          assertWithMessage("Invalid selection end")
                  .that(selector.getSelectionEnd())
                  .isEqualTo(94);
      }
  
      @Test
      public void testDetailNodeSelection() {
          final DetailNode javadoc = (DetailNode) model.getParseTreeTableModel()
                  .getChild(tree.getFirstChild().getNextSibling().getFirstChild(), 0);
          final CodeSelectorPresentation selector = new CodeSelectorPresentation(javadoc,
                  linesToPosition);
          selector.findSelectionPositions();
          assertWithMessage("Invalid selection start")
                  .that(selector.getSelectionStart())
                  .isEqualTo(74);
          assertWithMessage("Invalid selection end")
                  .that(selector.getSelectionEnd())
                  .isEqualTo(96);
      }
  
      @Test
      public void testDetailNodeLeafSelection() {
          final DetailNode javadoc = (DetailNode) model.getParseTreeTableModel()
                  .getChild(tree.getFirstChild().getNextSibling().getFirstChild(), 0);
          final DetailNode javadocLeaf = javadoc.getChildren()[2];
          final CodeSelectorPresentation selector = new CodeSelectorPresentation(javadocLeaf,
                  linesToPosition);
          selector.findSelectionPositions();
          assertWithMessage("Invalid selection start")
                  .that(selector.getSelectionStart())
                  .isEqualTo(76);
          assertWithMessage("Invalid selection end")
                  .that(selector.getSelectionEnd())
                  .isEqualTo(90);
      }
  
  }
  