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.regexp;
  
  import static com.google.common.truth.Truth.assertWithMessage;
  import static com.puppycrawl.tools.checkstyle.checks.regexp.RegexpCheck.MSG_DUPLICATE_REGEXP;
  import static com.puppycrawl.tools.checkstyle.checks.regexp.RegexpCheck.MSG_ILLEGAL_REGEXP;
  import static com.puppycrawl.tools.checkstyle.checks.regexp.RegexpCheck.MSG_REQUIRED_REGEXP;
  
  import org.junit.jupiter.api.Test;
  
  import com.puppycrawl.tools.checkstyle.AbstractModuleTestSupport;
  import com.puppycrawl.tools.checkstyle.DefaultConfiguration;
  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
  
  public class RegexpCheckTest extends AbstractModuleTestSupport {
  
      @Override
      protected String getPackageLocation() {
          return "com/puppycrawl/tools/checkstyle/checks/regexp/regexp";
      }
  
      @Test
      public void testGetAcceptableTokens() {
          final RegexpCheck regexpCheck = new RegexpCheck();
          assertWithMessage("RegexpCheck#getAcceptableTokens should return empty array by default")
                  .that(regexpCheck.getAcceptableTokens())
                  .isEmpty();
      }
  
      @Test
      public void testGetRequiredTokens() {
          final RegexpCheck checkObj = new RegexpCheck();
          assertWithMessage("RegexpCheck#getRequiredTokens should return empty array by default")
                  .that(checkObj.getRequiredTokens())
                  .isEmpty();
      }
  
      @Test
      public void testRequiredPass() throws Exception {
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic.java"), expected);
      }
  
      @Test
      public void testRequiredFail() throws Exception {
          final DefaultConfiguration checkConfig =
              createModuleConfig(RegexpCheck.class);
          checkConfig.addProperty("format", "This\\stext is not in the file");
          final String[] expected = {
              "0: " + getCheckMessage(MSG_REQUIRED_REGEXP, "This\\stext is not in the file"),
          };
          verify(checkConfig, getPath("InputRegexpSemantic2.java"), expected);
      }
  
      @Test
      public void testRequiredNoDuplicatesPass() throws Exception {
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic3.java"), expected);
      }
  
      @Test
      public void testSetDuplicatesTrue() throws Exception {
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic4.java"), expected);
      }
  
      @Test
      public void testRequiredNoDuplicatesFail() throws Exception {
          final String[] expected = {
              "27: " + getCheckMessage(MSG_DUPLICATE_REGEXP, "Boolean x = new Boolean"),
              "32: " + getCheckMessage(MSG_DUPLICATE_REGEXP, "Boolean x = new Boolean"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic5.java"), expected);
      }
  
      @Test
      public void testIllegalPass() throws Exception {
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic6.java"), expected);
      }
  
      @Test
      public void testStopEarly() throws Exception {
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpCheckStopEarly.java"), expected);
      }
  
      @Test
      public void testIllegalFailBelowErrorLimit() throws Exception {
          final String[] expected = {
              "15: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "^import"),
              "16: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "^import"),
              "17: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "^import"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic7.java"), expected);
      }
  
      @Test
      public void testIllegalFailAboveErrorLimit() throws Exception {
          final String error = "The error limit has been exceeded, "
                  + "the check is aborting, there may be more unreported errors.";
          final String[] expected = {
              "15: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "^import"),
              "16: " + getCheckMessage(MSG_ILLEGAL_REGEXP, error + "^import"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic8.java"), expected);
      }
  
      @Test
      public void testMessagePropertyGood()
              throws Exception {
          final String[] expected = {
              "77: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "Bad line :("),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic9.java"), expected);
      }
  
      @Test
      public void testMessagePropertyBad()
              throws Exception {
          final String[] expected = {
              "77: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "System\\.(out)|(err)\\.print(ln)?\\("),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic10.java"), expected);
      }
  
      @Test
      public void testMessagePropertyBad2()
              throws Exception {
          final String[] expected = {
              "77: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "System\\.(out)|(err)\\.print(ln)?\\("),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic11.java"), expected);
      }
  
      @Test
      public void testIgnoreCaseTrue() throws Exception {
          final String[] expected = {
              "77: " + getCheckMessage(MSG_ILLEGAL_REGEXP,
                      "(?i)SYSTEM\\.(OUT)|(ERR)\\.PRINT(LN)?\\("),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic12.java"), expected);
      }
  
      @Test
      public void testIgnoreCaseFalse() throws Exception {
          final String[] expectedTrue = {
              "77: " + getCheckMessage(MSG_ILLEGAL_REGEXP,
                      "(?i)SYSTEM\\.(OUT)|(ERR)\\.PRINT(LN)?\\("),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic13.java"), expectedTrue);
  
          final String[] expectedFalse = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpSemantic14.java"), expectedFalse);
      }
  
      @Test
      public void testIgnoreCommentsCppStyle() throws Exception {
          // See if the comment is removed properly
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsFalseCppStyle() throws Exception {
          // See if the comment is removed properly
          final String[] expected = {
              "16: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "don't\\suse trailing comments"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment2.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsBlockStyle() throws Exception {
          // See if the comment is removed properly
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment3.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsFalseBlockStyle() throws Exception {
          final String[] expected = {
              "31: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "c-style\\s1"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment4.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsMultipleBlockStyle() throws Exception {
          // See if a second comment on the same line is removed properly
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment5.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsMultiLine() throws Exception {
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment6.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsInlineStart() throws Exception {
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment7.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsInlineEnd() throws Exception {
          final String[] expected = {
              "34: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "int z"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment8.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsInlineMiddle() throws Exception {
          final String[] expected = {
              "35: " + getCheckMessage(MSG_ILLEGAL_REGEXP, "int y"),
          };
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment9.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsNoSpaces() throws Exception {
          // make sure the comment is not turned into spaces
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verifyWithInlineConfigParser(
                  getPath("InputRegexpTrailingComment10.java"), expected);
      }
  
      @Test
      public void testOnFileStartingWithEmptyLine() throws Exception {
          final DefaultConfiguration checkConfig = createModuleConfig(RegexpCheck.class);
          final String[] expected = CommonUtil.EMPTY_STRING_ARRAY;
          verify(checkConfig, getPath("InputRegexpStartingWithEmptyLine.java"), expected);
      }
  
      @Test
      public void testIgnoreCommentsCppStyleWithIllegalPatternFalse() throws Exception {
          // See if the comment is removed properly
          final DefaultConfiguration checkConfig =
                  createModuleConfig(RegexpCheck.class);
          checkConfig.addProperty("format", "don't use trailing comments");
          checkConfig.addProperty("illegalPattern", "false");
          checkConfig.addProperty("ignoreComments", "true");
          final String[] expected = {
              "0: " + getCheckMessage(MSG_REQUIRED_REGEXP, "don't use trailing comments"),
          };
          verify(checkConfig, getPath("InputRegexpTrailingComment11.java"), expected);
      }
  
  }
  