///////////////////////////////////////////////////////////////////////////////////////////////
   // 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.grammar.java21;
  
  import static com.google.common.truth.Truth.assertWithMessage;
  import static com.puppycrawl.tools.checkstyle.internal.utils.TestUtil.getExpectedThrowable;
  
  import java.io.File;
  
  import org.junit.jupiter.api.Test;
  
  import com.puppycrawl.tools.checkstyle.AbstractTreeTestSupport;
  import com.puppycrawl.tools.checkstyle.JavaParser;
  import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
  
  public class Java21AstRegressionTest extends AbstractTreeTestSupport {
  
      @Override
      public String getPackageLocation() {
          return "com/puppycrawl/tools/checkstyle/grammar/java21";
      }
  
      @Test
      public void testUnnamedVariableBasic() throws Exception {
          verifyAst(
                  getPath(
                          "ExpectedUnnamedVariableBasic.txt"),
                  getNonCompilablePath(
                          "InputUnnamedVariableBasic.java"));
      }
  
      @Test
      public void testUnnamedVariableSwitch() throws Exception {
          verifyAst(
                  getPath(
                          "ExpectedUnnamedVariableSwitch.txt"),
                  getNonCompilablePath(
                          "InputUnnamedVariableSwitch.java"));
      }
  
      @Test
      public void testTextBlockConsecutiveEscapes() throws Exception {
          verifyAst(
                  getPath(
                          "ExpectedTextBlockConsecutiveEscapes.txt"),
                  getPath(
                          "InputTextBlockConsecutiveEscapes.java"));
      }
  
      /**
       * Unusual test case, but important to prevent regressions. This fixture
       * places two text blocks back-to-back with no operator between them,
       * which is not a legal expression. We need to make sure the parser
       * correctly rejects this rather than misinterpreting the second text
       * block as part of the first.
       *
       * @throws Exception if an error occurs
       */
      @Test
      public void testTextBlockParsingFail() throws Exception {
          final File file =
                  new File(getPath("InputTextBlockParsingFail.java.fail"));
  
          final Throwable throwable =
                  getExpectedThrowable(CheckstyleException.class,
                          () -> JavaParser.parseFile(file, JavaParser.Options.WITHOUT_COMMENTS),
                          "Exception should be thrown due to parsing failure."
                  );
  
          assertWithMessage("Cause of CheckstyleException should be IllegalStateException.")
              .that(throwable.getCause())
              .isInstanceOf(IllegalStateException.class);
  
          assertWithMessage("Message of IllegalStateException should contain the parsing failure.")
              .that(throwable.getCause().getMessage())
              .contains("12:12: mismatched input '\"\"\"' expecting ';'");
  
      }
  
  }