[clang-tidy][NFC] Fix misc-const-correctness warnings (1/N) (#167030)

Start fixing `misc-const-correctness` warning to enable the check in
config

Author: vbvictor

clang-tools-extra/clang-tidy/ClangTidy.cpp

@@ -117,7 +117,8 @@ class ErrorReporter {
 
   void reportDiagnostic(const ClangTidyError &Error) {
     const tooling::DiagnosticMessage &Message = Error.Message;
-    SourceLocation Loc = getLocation(Message.FilePath, Message.FileOffset);
+    const SourceLocation Loc =
+        getLocation(Message.FilePath, Message.FileOffset);
     // Contains a pair for each attempted fix: location and whether the fix was
     // applied successfully.
     SmallVector<std::pair<SourceLocation, bool>, 4> FixLocations;
@@ -157,11 +158,11 @@ class ErrorReporter {
               // FIXME: Implement better conflict handling.
               llvm::errs() << "Trying to resolve conflict: "
                            << llvm::toString(std::move(Err)) << "\n";
-              unsigned NewOffset =
+              const unsigned NewOffset =
                   Replacements.getShiftedCodePosition(R.getOffset());
-              unsigned NewLength = Replacements.getShiftedCodePosition(
-                                       R.getOffset() + R.getLength()) -
-                                   NewOffset;
+              const unsigned NewLength = Replacements.getShiftedCodePosition(
+                                             R.getOffset() + R.getLength()) -
+                                         NewOffset;
               if (NewLength == R.getLength()) {
                 R = Replacement(R.getFilePath(), NewOffset, NewLength,
                                 R.getReplacementText());
@@ -200,7 +201,7 @@ class ErrorReporter {
 
       for (const auto &FileAndReplacements : FileReplacements) {
         Rewriter Rewrite(SourceMgr, LangOpts);
-        StringRef File = FileAndReplacements.first();
+        const StringRef File = FileAndReplacements.first();
         VFS.setCurrentWorkingDirectory(FileAndReplacements.second.BuildDir);
         llvm::ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
             SourceMgr.getFileManager().getBufferForFile(File);
@@ -210,7 +211,7 @@ class ErrorReporter {
           // FIXME: Maybe don't apply fixes for other files as well.
           continue;
         }
-        StringRef Code = Buffer.get()->getBuffer();
+        const StringRef Code = Buffer.get()->getBuffer();
         auto Style = format::getStyle(
             *Context.getOptionsForFile(File).FormatStyle, File, "none");
         if (!Style) {
@@ -262,7 +263,7 @@ class ErrorReporter {
     if (!File)
       return {};
 
-    FileID ID = SourceMgr.getOrCreateFileID(*File, SrcMgr::C_User);
+    const FileID ID = SourceMgr.getOrCreateFileID(*File, SrcMgr::C_User);
     return SourceMgr.getLocForStartOfFile(ID).getLocWithOffset(Offset);
   }
 
@@ -284,7 +285,8 @@ class ErrorReporter {
   }
 
   void reportNote(const tooling::DiagnosticMessage &Message) {
-    SourceLocation Loc = getLocation(Message.FilePath, Message.FileOffset);
+    const SourceLocation Loc =
+        getLocation(Message.FilePath, Message.FileOffset);
     auto Diag =
         Diags.Report(Loc, Diags.getCustomDiagID(DiagnosticsEngine::Note, "%0"))
         << Message.Message;
@@ -296,8 +298,9 @@ class ErrorReporter {
   CharSourceRange getRange(const FileByteRange &Range) {
     SmallString<128> AbsoluteFilePath{Range.FilePath};
     Files.makeAbsolutePath(AbsoluteFilePath);
-    SourceLocation BeginLoc = getLocation(AbsoluteFilePath, Range.FileOffset);
-    SourceLocation EndLoc = BeginLoc.getLocWithOffset(Range.Length);
+    const SourceLocation BeginLoc =
+        getLocation(AbsoluteFilePath, Range.FileOffset);
+    const SourceLocation EndLoc = BeginLoc.getLocWithOffset(Range.Length);
     // Retrieve the source range for applicable highlights and fixes. Macro
     // definition on the command line have locations in a virtual buffer and
     // don't have valid file paths and are therefore not applicable.
@@ -353,7 +356,8 @@ ClangTidyASTConsumerFactory::ClangTidyASTConsumerFactory(
   if (Context.canExperimentalCustomChecks() && custom::RegisterCustomChecks)
     custom::RegisterCustomChecks(Context.getOptions(), *CheckFactories);
 #endif
-  for (ClangTidyModuleRegistry::entry E : ClangTidyModuleRegistry::entries()) {
+  for (ClangTidyModuleRegistry::entry const E :
+       ClangTidyModuleRegistry::entries()) {
     std::unique_ptr<ClangTidyModule> Module = E.instantiate();
     Module->addCheckFactories(*CheckFactories);
   }
@@ -394,8 +398,9 @@ static CheckersList getAnalyzerCheckersAndPackages(ClangTidyContext &Context,
   // Always add all core checkers if any other static analyzer check is enabled.
   // This is currently necessary, as other path sensitive checks rely on the
   // core checkers.
-  for (StringRef CheckName : RegisteredCheckers) {
-    std::string ClangTidyCheckName((AnalyzerCheckNamePrefix + CheckName).str());
+  for (const StringRef CheckName : RegisteredCheckers) {
+    const std::string ClangTidyCheckName(
+        (AnalyzerCheckNamePrefix + CheckName).str());
 
     if (CheckName.starts_with("core") ||
         Context.isCheckEnabled(ClangTidyCheckName)) {
@@ -504,7 +509,7 @@ std::vector<std::string> ClangTidyASTConsumerFactory::getCheckNames() {
 
 ClangTidyOptions::OptionMap ClangTidyASTConsumerFactory::getCheckOptions() {
   ClangTidyOptions::OptionMap Options;
-  std::vector<std::unique_ptr<ClangTidyCheck>> Checks =
+  const std::vector<std::unique_ptr<ClangTidyCheck>> Checks =
       CheckFactories->createChecks(&Context);
   for (const auto &Check : Checks)
     Check->storeOptions(Options);
@@ -564,7 +569,7 @@ runClangTidy(clang::tidy::ClangTidyContext &Context,
                  std::make_shared<PCHContainerOperations>(), BaseFS);
 
   // Add extra arguments passed by the clang-tidy command-line.
-  ArgumentsAdjuster PerFileExtraArgumentsInserter =
+  const ArgumentsAdjuster PerFileExtraArgumentsInserter =
       [&Context](const CommandLineArguments &Args, StringRef Filename) {
         ClangTidyOptions Opts = Context.getOptionsForFile(Filename);
         CommandLineArguments AdjustedArgs = Args;
@@ -703,7 +708,7 @@ ChecksAndOptions getAllChecksAndOptions(bool AllowEnablingAnalyzerAlphaCheckers,
 
 #if CLANG_TIDY_ENABLE_STATIC_ANALYZER
   SmallString<64> Buffer(AnalyzerCheckNamePrefix);
-  size_t DefSize = Buffer.size();
+  const size_t DefSize = Buffer.size();
   for (const auto &AnalyzerCheck : AnalyzerOptions::getRegisteredCheckers(
            AllowEnablingAnalyzerAlphaCheckers)) {
     Buffer.truncate(DefSize);

clang-tools-extra/clang-tidy/ClangTidyCheck.cpp

@@ -161,7 +161,7 @@ ClangTidyCheck::OptionsView::getEnumInt(StringRef LocalName,
   if (Iter == CheckOptions.end())
     return std::nullopt;
 
-  StringRef Value = Iter->getValue().Value;
+  const StringRef Value = Iter->getValue().Value;
   StringRef Closest;
   unsigned EditDistance = 3;
   for (const auto &NameAndEnum : Mapping) {
@@ -173,7 +173,7 @@ ClangTidyCheck::OptionsView::getEnumInt(StringRef LocalName,
       EditDistance = 0;
       continue;
     }
-    unsigned Distance =
+    const unsigned Distance =
         Value.edit_distance(NameAndEnum.second, true, EditDistance);
     if (Distance < EditDistance) {
       EditDistance = Distance;

clang-tools-extra/clang-tidy/ClangTidyCheck.h

@@ -458,7 +458,7 @@ class ClangTidyCheck : public ast_matchers::MatchFinder::MatchCallback {
     template <typename T>
     std::enable_if_t<std::is_enum_v<T>, std::vector<NameAndValue>>
     typeEraseMapping() const {
-      ArrayRef<std::pair<T, StringRef>> Mapping =
+      const ArrayRef<std::pair<T, StringRef>> Mapping =
           OptionEnumMapping<T>::getEnumMapping();
       std::vector<NameAndValue> Result;
       Result.reserve(Mapping.size());

clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp

@@ -61,7 +61,7 @@ class ClangTidyDiagnosticRenderer : public DiagnosticRenderer {
     // FIXME: Remove this once there's a better way to pass check names than
     // appending the check name to the message in ClangTidyContext::diag and
     // using getCustomDiagID.
-    std::string CheckNameInMessage = " [" + Error.DiagnosticName + "]";
+    const std::string CheckNameInMessage = " [" + Error.DiagnosticName + "]";
     Message.consume_back(CheckNameInMessage);
 
     auto TidyMessage =
@@ -77,7 +77,7 @@ class ClangTidyDiagnosticRenderer : public DiagnosticRenderer {
       if (SourceRange.isCharRange())
         return SourceRange;
       assert(SourceRange.isTokenRange());
-      SourceLocation End = Lexer::getLocForEndOfToken(
+      const SourceLocation End = Lexer::getLocForEndOfToken(
           SourceRange.getEnd(), 0, Loc.getManager(), LangOpts);
       return CharSourceRange::getCharRange(SourceRange.getBegin(), End);
     };
@@ -114,14 +114,14 @@ class ClangTidyDiagnosticRenderer : public DiagnosticRenderer {
         Level == DiagnosticsEngine::Note ? &Error.Notes.back() : &Error.Message;
 
     for (const auto &FixIt : Hints) {
-      CharSourceRange Range = FixIt.RemoveRange;
+      const CharSourceRange Range = FixIt.RemoveRange;
       assert(Range.getBegin().isValid() && Range.getEnd().isValid() &&
              "Invalid range in the fix-it hint.");
       assert(Range.getBegin().isFileID() && Range.getEnd().isFileID() &&
              "Only file locations supported in fix-it hints.");
 
-      tooling::Replacement Replacement(Loc.getManager(), Range,
-                                       FixIt.CodeToInsert);
+      const tooling::Replacement Replacement(Loc.getManager(), Range,
+                                             FixIt.CodeToInsert);
       llvm::Error Err =
           DiagWithFix->Fix[Replacement.getFilePath()].add(Replacement);
       // FIXME: better error handling (at least, don't let other replacements be
@@ -177,7 +177,7 @@ DiagnosticBuilder ClangTidyContext::diag(
     StringRef CheckName, SourceLocation Loc, StringRef Description,
     DiagnosticIDs::Level Level /* = DiagnosticIDs::Warning*/) {
   assert(Loc.isValid());
-  unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
+  const unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
       Level, (Description + " [" + CheckName + "]").str());
   CheckNamesByDiagnosticID.try_emplace(ID, CheckName);
   return DiagEngine->Report(Loc, ID);
@@ -186,7 +186,7 @@ DiagnosticBuilder ClangTidyContext::diag(
 DiagnosticBuilder ClangTidyContext::diag(
     StringRef CheckName, StringRef Description,
     DiagnosticIDs::Level Level /* = DiagnosticIDs::Warning*/) {
-  unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
+  const unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
       Level, (Description + " [" + CheckName + "]").str());
   CheckNamesByDiagnosticID.try_emplace(ID, CheckName);
   return DiagEngine->Report(ID);
@@ -195,10 +195,11 @@ DiagnosticBuilder ClangTidyContext::diag(
 DiagnosticBuilder ClangTidyContext::diag(const tooling::Diagnostic &Error) {
   SourceManager &SM = DiagEngine->getSourceManager();
   FileManager &FM = SM.getFileManager();
-  FileEntryRef File = llvm::cantFail(FM.getFileRef(Error.Message.FilePath));
-  FileID ID = SM.getOrCreateFileID(File, SrcMgr::C_User);
-  SourceLocation FileStartLoc = SM.getLocForStartOfFile(ID);
-  SourceLocation Loc = FileStartLoc.getLocWithOffset(
+  const FileEntryRef File =
+      llvm::cantFail(FM.getFileRef(Error.Message.FilePath));
+  const FileID ID = SM.getOrCreateFileID(File, SrcMgr::C_User);
+  const SourceLocation FileStartLoc = SM.getLocForStartOfFile(ID);
+  const SourceLocation Loc = FileStartLoc.getLocWithOffset(
       static_cast<SourceLocation::IntTy>(Error.Message.FileOffset));
   return diag(Error.DiagnosticName, Loc, Error.Message.Message,
               static_cast<DiagnosticIDs::Level>(Error.DiagLevel));
@@ -214,7 +215,7 @@ bool ClangTidyContext::shouldSuppressDiagnostic(
     DiagnosticsEngine::Level DiagLevel, const Diagnostic &Info,
     SmallVectorImpl<tooling::Diagnostic> &NoLintErrors, bool AllowIO,
     bool EnableNoLintBlocks) {
-  std::string CheckName = getCheckName(Info.getID());
+  const std::string CheckName = getCheckName(Info.getID());
   return NoLintHandler.shouldSuppress(DiagLevel, Info, CheckName, NoLintErrors,
                                       AllowIO, EnableNoLintBlocks);
 }
@@ -226,7 +227,7 @@ void ClangTidyContext::setSourceManager(SourceManager *SourceMgr) {
 static bool parseFileExtensions(llvm::ArrayRef<std::string> AllFileExtensions,
                                 FileExtensionsSet &FileExtensions) {
   FileExtensions.clear();
-  for (StringRef Suffix : AllFileExtensions) {
+  for (const StringRef Suffix : AllFileExtensions) {
     StringRef Extension = Suffix.trim();
     if (!llvm::all_of(Extension, isAlphanumeric))
       return false;
@@ -294,11 +295,11 @@ bool ClangTidyContext::treatAsError(StringRef CheckName) const {
 }
 
 std::string ClangTidyContext::getCheckName(unsigned DiagnosticID) const {
-  std::string ClangWarningOption = std::string(
+  const std::string ClangWarningOption = std::string(
       DiagEngine->getDiagnosticIDs()->getWarningOptionForDiag(DiagnosticID));
   if (!ClangWarningOption.empty())
     return "clang-diagnostic-" + ClangWarningOption;
-  llvm::DenseMap<unsigned, std::string>::const_iterator I =
+  const llvm::DenseMap<unsigned, std::string>::const_iterator I =
       CheckNamesByDiagnosticID.find(DiagnosticID);
   if (I != CheckNamesByDiagnosticID.end())
     return I->second;
@@ -316,7 +317,7 @@ ClangTidyDiagnosticConsumer::ClangTidyDiagnosticConsumer(
 
 void ClangTidyDiagnosticConsumer::finalizeLastError() {
   if (!Errors.empty()) {
-    ClangTidyError &Error = Errors.back();
+    const ClangTidyError &Error = Errors.back();
     if (Error.DiagnosticName == "clang-tidy-config") {
       // Never ignore these.
     } else if (!Context.isCheckEnabled(Error.DiagnosticName) &&
@@ -436,8 +437,8 @@ void ClangTidyDiagnosticConsumer::HandleDiagnostic(
       Level = ClangTidyError::Remark;
     }
 
-    bool IsWarningAsError = DiagLevel == DiagnosticsEngine::Warning &&
-                            Context.treatAsError(CheckName);
+    const bool IsWarningAsError = DiagLevel == DiagnosticsEngine::Warning &&
+                                  Context.treatAsError(CheckName);
     Errors.emplace_back(CheckName, Level, Context.getCurrentBuildDirectory(),
                         IsWarningAsError);
   }
@@ -491,8 +492,9 @@ void ClangTidyDiagnosticConsumer::forwardDiagnostic(const Diagnostic &Info) {
   // Acquire a diagnostic ID also in the external diagnostics engine.
   auto DiagLevelAndFormatString =
       Context.getDiagLevelAndFormatString(Info.getID(), Info.getLocation());
-  unsigned ExternalID = ExternalDiagEngine->getDiagnosticIDs()->getCustomDiagID(
-      DiagLevelAndFormatString.first, DiagLevelAndFormatString.second);
+  const unsigned ExternalID =
+      ExternalDiagEngine->getDiagnosticIDs()->getCustomDiagID(
+          DiagLevelAndFormatString.first, DiagLevelAndFormatString.second);
 
   // Forward the details.
   auto Builder = ExternalDiagEngine->Report(Info.getLocation(), ExternalID);
@@ -501,7 +503,7 @@ void ClangTidyDiagnosticConsumer::forwardDiagnostic(const Diagnostic &Info) {
   for (auto Range : Info.getRanges())
     Builder << Range;
   for (unsigned Index = 0; Index < Info.getNumArgs(); ++Index) {
-    DiagnosticsEngine::ArgumentKind Kind = Info.getArgKind(Index);
+    const DiagnosticsEngine::ArgumentKind Kind = Info.getArgKind(Index);
     switch (Kind) {
     case clang::DiagnosticsEngine::ak_std_string:
       Builder << Info.getArgStdStr(Index);
@@ -574,7 +576,7 @@ void ClangTidyDiagnosticConsumer::checkFilters(SourceLocation Location,
   // FIXME: We start with a conservative approach here, but the actual type of
   // location needed depends on the check (in particular, where this check wants
   // to apply fixes).
-  FileID FID = Sources.getDecomposedExpansionLoc(Location).first;
+  const FileID FID = Sources.getDecomposedExpansionLoc(Location).first;
   OptionalFileEntryRef File = Sources.getFileEntryRefForID(FID);
 
   // -DMACRO definitions on the command line have locations in a virtual buffer
@@ -585,13 +587,13 @@ void ClangTidyDiagnosticConsumer::checkFilters(SourceLocation Location,
     return;
   }
 
-  StringRef FileName(File->getName());
+  const StringRef FileName(File->getName());
   LastErrorRelatesToUserCode = LastErrorRelatesToUserCode ||
                                Sources.isInMainFile(Location) ||
                                (getHeaderFilter()->match(FileName) &&
                                 !getExcludeHeaderFilter()->match(FileName));
 
-  unsigned LineNumber = Sources.getExpansionLineNumber(Location);
+  const unsigned LineNumber = Sources.getExpansionLineNumber(Location);
   LastErrorPassesLineFilter =
       LastErrorPassesLineFilter || passesLineFilter(FileName, LineNumber);
 }
@@ -707,8 +709,8 @@ void ClangTidyDiagnosticConsumer::removeIncompatibleErrors() {
   for (unsigned I = 0; I < ErrorFixes.size(); ++I) {
     for (const auto &FileAndReplace : *ErrorFixes[I].second) {
       for (const auto &Replace : FileAndReplace.second) {
-        unsigned Begin = Replace.getOffset();
-        unsigned End = Begin + Replace.getLength();
+        const unsigned Begin = Replace.getOffset();
+        const unsigned End = Begin + Replace.getLength();
         auto &Events = FileEvents[Replace.getFilePath()];
         if (Begin == End) {
           Events.emplace_back(Begin, End, Event::ET_Insert, I, Sizes[I]);
@@ -767,7 +769,7 @@ struct LessClangTidyError {
 };
 struct EqualClangTidyError {
   bool operator()(const ClangTidyError &LHS, const ClangTidyError &RHS) const {
-    LessClangTidyError Less;
+    const LessClangTidyError Less;
     return !Less(LHS, RHS) && !Less(RHS, LHS);
   }
 };
@@ -803,7 +805,7 @@ void ClangTidyDiagnosticConsumer::removeDuplicatedDiagnosticsOfAliasCheckers() {
   auto IT = Errors.begin();
   while (IT != Errors.end()) {
     ClangTidyError &Error = *IT;
-    std::pair<UniqueErrorSet::iterator, bool> Inserted =
+    const std::pair<UniqueErrorSet::iterator, bool> Inserted =
         UniqueErrors.insert(&Error);
 
     // Unique error, we keep it and move along.

clang-tools-extra/clang-tidy/ClangTidyOptions.cpp

@@ -119,7 +119,7 @@ void yamlize(IO &IO, ClangTidyOptions::OptionMap &Val, bool,
       yamlize(IO, NOpts->Options, true, Ctx);
     } else if (isa<MappingNode>(I.getCurrentNode())) {
       IO.beginMapping();
-      for (StringRef Key : IO.keys()) {
+      for (const StringRef Key : IO.keys()) {
         // Requires 'llvm::yaml::IO' to accept 'StringRef'
         // NOLINTNEXTLINE(bugprone-suspicious-stringview-data-usage)
         IO.mapRequired(Key.data(), Val[Key].Value);
@@ -392,7 +392,7 @@ llvm::ErrorOr<llvm::SmallString<128>>
 FileOptionsBaseProvider::getNormalizedAbsolutePath(llvm::StringRef Path) {
   assert(FS && "FS must be set.");
   llvm::SmallString<128> NormalizedAbsolutePath = {Path};
-  std::error_code Err = FS->makeAbsolute(NormalizedAbsolutePath);
+  const std::error_code Err = FS->makeAbsolute(NormalizedAbsolutePath);
   if (Err)
     return Err;
   llvm::sys::path::remove_dots(NormalizedAbsolutePath, /*remove_dot_dot=*/true);
@@ -463,16 +463,16 @@ FileOptionsProvider::getRawOptions(StringRef FileName) {
   LLVM_DEBUG(llvm::dbgs() << "Getting options for file " << FileName
                           << "...\n");
 
-  llvm::ErrorOr<llvm::SmallString<128>> AbsoluteFilePath =
+  const llvm::ErrorOr<llvm::SmallString<128>> AbsoluteFilePath =
       getNormalizedAbsolutePath(FileName);
   if (!AbsoluteFilePath)
     return {};
 
   std::vector<OptionsSource> RawOptions =
       DefaultOptionsProvider::getRawOptions(AbsoluteFilePath->str());
   addRawFileOptions(AbsoluteFilePath->str(), RawOptions);
-  OptionsSource CommandLineOptions(OverrideOptions,
-                                   OptionsSourceTypeCheckCommandLineOption);
+  const OptionsSource CommandLineOptions(
+      OverrideOptions, OptionsSourceTypeCheckCommandLineOption);
 
   RawOptions.push_back(CommandLineOptions);
   return RawOptions;
@@ -502,7 +502,7 @@ FileOptionsBaseProvider::tryReadConfigFile(StringRef Directory) {
 
     llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Text =
         FS->getBufferForFile(ConfigFile);
-    if (std::error_code EC = Text.getError()) {
+    if (const std::error_code EC = Text.getError()) {
       llvm::errs() << "Can't read " << ConfigFile << ": " << EC.message()
                    << "\n";
       continue;