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.checks.naming;
  
  import static com.google.common.truth.Truth.assertWithMessage;
  import static com.puppycrawl.tools.checkstyle.checks.naming.AbstractNameCheck.MSG_INVALID_PATTERN;
  
  import org.junit.jupiter.api.Test;
  
  import com.puppycrawl.tools.checkstyle.AbstractModuleTestSupport;
  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
  
  public class IllegalIdentifierNameCheckTest extends AbstractModuleTestSupport {
  
      @Override
      protected String getPackageLocation() {
          return "com/puppycrawl/tools/checkstyle/checks/naming/illegalidentifiername";
      }
  
      @Test
      public void testGetAcceptableTokens() {
          final IllegalIdentifierNameCheck illegalIdentifierNameCheck =
              new IllegalIdentifierNameCheck();
          final int[] expected = {
              TokenTypes.CLASS_DEF,
              TokenTypes.INTERFACE_DEF,
              TokenTypes.ENUM_DEF,
              TokenTypes.ANNOTATION_DEF,
              TokenTypes.ANNOTATION_FIELD_DEF,
              TokenTypes.PARAMETER_DEF,
              TokenTypes.VARIABLE_DEF,
              TokenTypes.METHOD_DEF,
              TokenTypes.ENUM_CONSTANT_DEF,
              TokenTypes.PATTERN_VARIABLE_DEF,
              TokenTypes.RECORD_DEF,
              TokenTypes.RECORD_COMPONENT_DEF,
              TokenTypes.LAMBDA,
          };
  
          assertWithMessage("Default acceptable tokens are invalid")
              .that(illegalIdentifierNameCheck.getAcceptableTokens())
              .isEqualTo(expected);
      }
  
      @Test
      public void testGetRequiredTokens() {
          final IllegalIdentifierNameCheck illegalIdentifierNameCheck =
              new IllegalIdentifierNameCheck();
          final int[] expected = CommonUtil.EMPTY_INT_ARRAY;
  
          assertWithMessage("Default required tokens are invalid")
              .that(illegalIdentifierNameCheck.getRequiredTokens())
              .isEqualTo(expected);
      }
  
      @Test
      public void testIllegalIdentifierNameDefault() throws Exception {
  
          final String format = "(?i)^(?!(record|yield|var|permits|sealed|_)$).+$";
  
          final String[] expected = {
              "21:25: " + getCheckMessage(MSG_INVALID_PATTERN, "record", format),
              "22:24: " + getCheckMessage(MSG_INVALID_PATTERN, "record", format),
              "28:13: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "30:21: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "45:9: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "57:13: " + getCheckMessage(MSG_INVALID_PATTERN, "var", format),
              "59:13: " + getCheckMessage(MSG_INVALID_PATTERN, "record", format),
              "61:16: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "63:16: " + getCheckMessage(MSG_INVALID_PATTERN, "Record", format),
              "64:25: " + getCheckMessage(MSG_INVALID_PATTERN, "record", format),
              "74:37: " + getCheckMessage(MSG_INVALID_PATTERN, "record", format),
              "74:52: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "74:69: " + getCheckMessage(MSG_INVALID_PATTERN, "var", format),
          };
          verifyWithInlineConfigParser(
                  getNonCompilablePath("InputIllegalIdentifierName.java"), expected);
      }
  
      @Test
      public void testIllegalIdentifierNameOpenTransitive() throws Exception {
          final String format = "(?i)^(?!(record|yield|var|permits|sealed|open|transitive)$).+$";
  
          final String[] expected = {
              "21:25: " + getCheckMessage(MSG_INVALID_PATTERN, "record", format),
              "22:24: " + getCheckMessage(MSG_INVALID_PATTERN, "record", format),
              "28:13: " + getCheckMessage(MSG_INVALID_PATTERN, "open", format),
              "30:21: " + getCheckMessage(MSG_INVALID_PATTERN, "transitive", format),
              "45:9: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "57:13: " + getCheckMessage(MSG_INVALID_PATTERN, "var", format),
              "59:13: " + getCheckMessage(MSG_INVALID_PATTERN, "record", format),
              "61:16: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "63:16: " + getCheckMessage(MSG_INVALID_PATTERN, "Record", format),
              "64:25: " + getCheckMessage(MSG_INVALID_PATTERN, "transitive", format),
              "73:16: " + getCheckMessage(MSG_INVALID_PATTERN, "Transitive", format),
              "76:37: " + getCheckMessage(MSG_INVALID_PATTERN, "transitive", format),
              "76:56: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "76:72: " + getCheckMessage(MSG_INVALID_PATTERN, "var", format),
          };
          verifyWithInlineConfigParser(
                  getNonCompilablePath("InputIllegalIdentifierNameOpenTransitive.java"), expected);
      }
  
      @Test
      public void testIllegalIdentifierNameParameterReceiver() throws Exception {
  
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
  
          verifyWithInlineConfigParser(
                  getNonCompilablePath("InputIllegalIdentifierNameParameterReceiver.java"),
              expected);
      }
  
      @Test
      public void testIllegalIdentifierNameUnderscore() throws Exception {
          final String format = "(?i)^(?!(record|yield|var|permits|sealed|_)$).+$";
  
          final String[] expected = {
              "18:12: " + getCheckMessage(MSG_INVALID_PATTERN, "_", format),
          };
          verifyWithInlineConfigParser(
                  getNonCompilablePath("InputIllegalIdentifierNameUnderscore.java"), expected);
      }
  
      @Test
      public void testIllegalIdentifierNameLambda() throws Exception {
          final String format = "(?i)^(?!(record|yield|var|permits|sealed|_)$).+$";
  
          final String[] expected = {
              "19:39: " + getCheckMessage(MSG_INVALID_PATTERN, "var", format),
              "20:40: " + getCheckMessage(MSG_INVALID_PATTERN, "var", format),
              "32:9: " + getCheckMessage(MSG_INVALID_PATTERN, "var", format),
              "35:9: " + getCheckMessage(MSG_INVALID_PATTERN, "yield", format),
              "42:47: " + getCheckMessage(MSG_INVALID_PATTERN, "var", format),
          };
          verifyWithInlineConfigParser(
                  getNonCompilablePath("InputIllegalIdentifierNameLambda.java"), expected);
      }
  }
  