[clang-tidy][NFC] Refactor ClangTidyDiagnosticConsumer files

[carlosgalvezp]

Summary

Currently, ClangTidyDiagnosticConsumer defines 2 additional
classes: ClangTidyContext and ClangTidyError. A reader does
not expect them to be there, and a file needing only one
of them needs to include the heavy ClangTidyDiangosticConsumer.h,
increasing compilation time.

Refactor by moving these classes into their own set of .h/.cpp files.
Besides readability, compilation time is also improved.
Adjust includes accordingly.

[Eugene.Zelenko]

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

41

Shouldn't namespaces be used instead?

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

19

Shouldn't namespaces be used instead?

[carlosgalvezp]

I agree with the comments, but I didn't want to touch any code other than moving things around, since it's hard to see the changes in the diff otherwise. I was also unsure if this was "LLVM convention" or a mistake. I'm happy to fix in a separate patch if that's OK?

[whisperity]

What is the motivation behind the change? Can we be sure that these classes that were moved out weren't details to the context itself, and are understandable, usable, and can be relied upon without the context object?

---

In D113848#3130542, @carlosgalvezp wrote:

I agree with the comments, but I didn't want to touch any code other than moving things around, since it's hard to see the changes in the diff otherwise. I was also unsure if this was "LLVM convention" or a mistake. I'm happy to fix in a separate patch if that's OK?

I think you can fix it now, LLVM style doesn't indent stuff that's within a namespace, so it won't change the meaningful part of the diff visually.

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

41–42

In general, you'd also want to make it more explicit by saying

using namespace clang;
using namespace clang::tidy;

and not rely on precisely one tidy being visible from the previous set of available declarations.

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

36–37

Is this formatted properly? I thought the appropriate closing comment is // namespace blah, without the end. 😲

[carlosgalvezp]

What is the motivation behind the change?

The motivation is cleaning the file to make it easier to find things. As a n00b to clang-tidy I find it a bit hard to navigate the code and find the different classes - they are not where I expect them to be. The ClangTidyContext is a core class used in other places than just DiagnosticConsumer, so I think it makes sense to keep it on it's own file so it's easy to find. For example:

ClangTidyCheck(StringRef CheckName, ClangTidyContext *Context);

It's unintuitive to have to import the DiagnosticConsumer to get the Context

In general I think it's a good principle to keep a 1:1 mapping between public classes and files. Naturally, internal helper classes can be kept in the same file as the "main" class. This brings build-time improvements as well but I'd say they are negligible.

Let me know if you agree, otherwise I can of course drop this :)

[carlosgalvezp]

• Rebased.
• Addressed comments.

clang-tools-extra/clang-tidy/CMakeLists.txt

 set(LLVM_LINK_COMPONENTS
   FrontendOpenMP
   Support
   )
 
 configure_file(
   ${CMAKE_CURRENT_SOURCE_DIR}/clang-tidy-config.h.cmake
   ${CMAKE_CURRENT_BINARY_DIR}/clang-tidy-config.h)
 include_directories(BEFORE ${CMAKE_CURRENT_BINARY_DIR})
 
 add_clang_library(clangTidy
   ClangTidy.cpp
   ClangTidyCheck.cpp
+  ClangTidyContext.cpp
+  ClangTidyError.cpp
   ClangTidyModule.cpp
   ClangTidyDiagnosticConsumer.cpp
   ClangTidyOptions.cpp
   ClangTidyProfiling.cpp
   ExpandModularHeadersPPCallbacks.cpp
   GlobList.cpp
 
   DEPENDS

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

 ///    http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
 ///  for details on setting it up with LLVM source tree.
 ///
 //===----------------------------------------------------------------------===//
 
 #include "ClangTidy.h"
 #include "ClangTidyCheck.h"
 #include "ClangTidyDiagnosticConsumer.h"
+#include "ClangTidyError.h"
 #include "ClangTidyModuleRegistry.h"
 #include "ClangTidyProfiling.h"
 #include "ExpandModularHeadersPPCallbacks.h"
 #include "clang-tidy-config.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include "clang/Format/Format.h"
 #include "clang/Frontend/ASTConsumers.h"

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

 //===--- ClangTidyCheck.h - clang-tidy --------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYCHECK_H
 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYCHECK_H
 
-#include "ClangTidyDiagnosticConsumer.h"
+#include "ClangTidyContext.h"
 #include "ClangTidyOptions.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include "clang/Basic/Diagnostic.h"
 #include "llvm/ADT/Optional.h"
 #include <type_traits>
 #include <utility>
 #include <vector>
 

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

+//===--- ClangTidyContext.h - clang-tidy ------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYCONTEXT_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYCONTEXT_H
+
+#include "ClangTidyOptions.h"
+#include "ClangTidyProfiling.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Tooling/Core/Diagnostic.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/Support/Regex.h"
+
+namespace clang {
+
+class ASTContext;
+class SourceManager;
+
+namespace tidy {
+struct ClangTidyError;
+
+/// Contains displayed and ignored diagnostic counters for a ClangTidy run.
+struct ClangTidyStats {
+  unsigned ErrorsDisplayed = 0;
+  unsigned ErrorsIgnoredCheckFilter = 0;
+  unsigned ErrorsIgnoredNOLINT = 0;
+  unsigned ErrorsIgnoredNonUserCode = 0;
+  unsigned ErrorsIgnoredLineFilter = 0;
+
+  unsigned errorsIgnored() const {
+    return ErrorsIgnoredNOLINT + ErrorsIgnoredCheckFilter +
+           ErrorsIgnoredNonUserCode + ErrorsIgnoredLineFilter;
+  }
+};
+
+/// Every \c ClangTidyCheck reports errors through a \c DiagnosticsEngine
+/// provided by this context.
+///
+/// A \c ClangTidyCheck always has access to the active context to report
+/// warnings like:
+/// \code
+/// Context->Diag(Loc, "Single-argument constructors must be explicit")
+///     << FixItHint::CreateInsertion(Loc, "explicit ");
+/// \endcode
+class ClangTidyContext {
+public:
+  /// Initializes \c ClangTidyContext instance.
+  ClangTidyContext(std::unique_ptr<ClangTidyOptionsProvider> OptionsProvider,
+                   bool AllowEnablingAnalyzerAlphaCheckers = false);
+  /// Sets the DiagnosticsEngine that diag() will emit diagnostics to.
+  // FIXME: this is required initialization, and should be a constructor param.
+  // Fix the context -> diag engine -> consumer -> context initialization cycle.
+  void setDiagnosticsEngine(DiagnosticsEngine *DiagEngine) {
+    this->DiagEngine = DiagEngine;
+  }
+
+  ~ClangTidyContext();
+
+  /// Report any errors detected using this method.
+  ///
+  /// This is still under heavy development and will likely change towards using
+  /// tablegen'd diagnostic IDs.
+  /// FIXME: Figure out a way to manage ID spaces.
+  DiagnosticBuilder diag(StringRef CheckName, SourceLocation Loc,
+                         StringRef Message,
+                         DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
+
+  DiagnosticBuilder diag(StringRef CheckName, StringRef Message,
+                         DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
+
+  DiagnosticBuilder diag(const ClangTidyError &Error);
+
+  /// Report any errors to do with reading the configuration using this method.
+  DiagnosticBuilder
+  configurationDiag(StringRef Message,
+                    DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
+
+  /// Sets the \c SourceManager of the used \c DiagnosticsEngine.
+  ///
+  /// This is called from the \c ClangTidyCheck base class.
+  void setSourceManager(SourceManager *SourceMgr);
+
+  /// Should be called when starting to process new translation unit.
+  void setCurrentFile(StringRef File);
+
+  /// Returns the main file name of the current translation unit.
+  StringRef getCurrentFile() const { return CurrentFile; }
+
+  /// Sets ASTContext for the current translation unit.
+  void setASTContext(ASTContext *Context);
+
+  /// Gets the language options from the AST context.
+  const LangOptions &getLangOpts() const { return LangOpts; }
+
+  /// Returns the name of the clang-tidy check which produced this
+  /// diagnostic ID.
+  std::string getCheckName(unsigned DiagnosticID) const;
+
+  /// Returns \c true if the check is enabled for the \c CurrentFile.
+  ///
+  /// The \c CurrentFile can be changed using \c setCurrentFile.
+  bool isCheckEnabled(StringRef CheckName) const;
+
+  /// Returns \c true if the check should be upgraded to error for the
+  /// \c CurrentFile.
+  bool treatAsError(StringRef CheckName) const;
+
+  /// Returns global options.
+  const ClangTidyGlobalOptions &getGlobalOptions() const;
+
+  /// Returns options for \c CurrentFile.
+  ///
+  /// The \c CurrentFile can be changed using \c setCurrentFile.
+  const ClangTidyOptions &getOptions() const;
+
+  /// Returns options for \c File. Does not change or depend on
+  /// \c CurrentFile.
+  ClangTidyOptions getOptionsForFile(StringRef File) const;
+
+  /// Returns \c ClangTidyStats containing issued and ignored diagnostic
+  /// counters.
+  const ClangTidyStats &getStats() const { return Stats; }
+
+  /// Control profile collection in clang-tidy.
+  void setEnableProfiling(bool Profile);
+  bool getEnableProfiling() const { return Profile; }
+
+  /// Control storage of profile date.
+  void setProfileStoragePrefix(StringRef ProfilePrefix);
+  llvm::Optional<ClangTidyProfiling::StorageParams>
+  getProfileStorageParams() const;
+
+  /// Should be called when starting to process new translation unit.
+  void setCurrentBuildDirectory(StringRef BuildDirectory) {
+    CurrentBuildDirectory = std::string(BuildDirectory);
+  }
+
+  /// Returns build directory of the current translation unit.
+  const std::string &getCurrentBuildDirectory() const {
+    return CurrentBuildDirectory;
+  }
+
+  /// If the experimental alpha checkers from the static analyzer can be
+  /// enabled.
+  bool canEnableAnalyzerAlphaCheckers() const {
+    return AllowEnablingAnalyzerAlphaCheckers;
+  }
+
+  using DiagLevelAndFormatString = std::pair<DiagnosticIDs::Level, std::string>;
+  DiagLevelAndFormatString getDiagLevelAndFormatString(unsigned DiagnosticID,
+                                                       SourceLocation Loc) {
+    return DiagLevelAndFormatString(
+        static_cast<DiagnosticIDs::Level>(
+            DiagEngine->getDiagnosticLevel(DiagnosticID, Loc)),
+        std::string(
+            DiagEngine->getDiagnosticIDs()->getDescription(DiagnosticID)));
+  }
+
+private:
+  // Writes to Stats.
+  friend class ClangTidyDiagnosticConsumer;
+
+  DiagnosticsEngine *DiagEngine;
+  std::unique_ptr<ClangTidyOptionsProvider> OptionsProvider;
+
+  std::string CurrentFile;
+  ClangTidyOptions CurrentOptions;
+  class CachedGlobList;
+  std::unique_ptr<CachedGlobList> CheckFilter;
+  std::unique_ptr<CachedGlobList> WarningAsErrorFilter;
+
+  LangOptions LangOpts;
+
+  ClangTidyStats Stats;
+
+  std::string CurrentBuildDirectory;
+
+  llvm::DenseMap<unsigned, std::string> CheckNamesByDiagnosticID;
+
+  bool Profile;
+  std::string ProfilePrefix;
+
+  bool AllowEnablingAnalyzerAlphaCheckers;
+};
+
+} // end namespace tidy
+} // end namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYCONTEXT_H

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

+//===--- tools/extra/clang-tidy/ClangTidyContext.cpp ---------------------=== //
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+///  \file This file implements the ClangTidyContext class.
+///
+///  This tool uses the Clang Tooling infrastructure, see
+///    http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
+///  for details on setting it up with LLVM source tree.
+///
+//===----------------------------------------------------------------------===//
+
+#include "ClangTidyContext.h"
+#include "ClangTidyError.h"
+#include "ClangTidyOptions.h"
+#include "GlobList.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/ASTDiagnostic.h"
+#include "clang/AST/Attr.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/DiagnosticOptions.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Frontend/DiagnosticRenderer.h"
+#include "clang/Lex/Lexer.h"
+#include "clang/Tooling/Core/Diagnostic.h"
+#include "clang/Tooling/Core/Replacement.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/Support/FormatVariadic.h"
+#include "llvm/Support/Regex.h"
+#include <tuple>
+#include <utility>
+#include <vector>
+
+namespace clang {
+namespace tidy {
+
+class ClangTidyContext::CachedGlobList {
+public:
+  CachedGlobList(StringRef Globs) : Globs(Globs) {}
+
+  bool contains(StringRef S) {
+    switch (auto &Result = Cache[S]) {
+    case Yes:
+      return true;
+    case No:
+      return false;
+    case None:
+      Result = Globs.contains(S) ? Yes : No;
+      return Result == Yes;
+    }
+    llvm_unreachable("invalid enum");
+  }
+
+private:
+  GlobList Globs;
+  enum Tristate { None, Yes, No };
+  llvm::StringMap<Tristate> Cache;
+};
+
+ClangTidyContext::ClangTidyContext(
+    std::unique_ptr<ClangTidyOptionsProvider> OptionsProvider,
+    bool AllowEnablingAnalyzerAlphaCheckers)
+    : DiagEngine(nullptr), OptionsProvider(std::move(OptionsProvider)),
+      Profile(false),
+      AllowEnablingAnalyzerAlphaCheckers(AllowEnablingAnalyzerAlphaCheckers) {
+  // Before the first translation unit we can get errors related to command-line
+  // parsing, use empty string for the file name in this case.
+  setCurrentFile("");
+}
+
+ClangTidyContext::~ClangTidyContext() = default;
+
+DiagnosticBuilder ClangTidyContext::diag(
+    StringRef CheckName, SourceLocation Loc, StringRef Description,
+    DiagnosticIDs::Level Level /* = DiagnosticIDs::Warning*/) {
+  assert(Loc.isValid());
+  unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
+      Level, (Description + " [" + CheckName + "]").str());
+  CheckNamesByDiagnosticID.try_emplace(ID, CheckName);
+  return DiagEngine->Report(Loc, ID);
+}
+
+DiagnosticBuilder ClangTidyContext::diag(
+    StringRef CheckName, StringRef Description,
+    DiagnosticIDs::Level Level /* = DiagnosticIDs::Warning*/) {
+  unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
+      Level, (Description + " [" + CheckName + "]").str());
+  CheckNamesByDiagnosticID.try_emplace(ID, CheckName);
+  return DiagEngine->Report(ID);
+}
+
+DiagnosticBuilder ClangTidyContext::diag(const ClangTidyError &Error) {
+  SourceManager &SM = DiagEngine->getSourceManager();
+  llvm::ErrorOr<const FileEntry *> File =
+      SM.getFileManager().getFile(Error.Message.FilePath);
+  FileID ID = SM.getOrCreateFileID(*File, SrcMgr::C_User);
+  SourceLocation FileStartLoc = SM.getLocForStartOfFile(ID);
+  SourceLocation Loc = FileStartLoc.getLocWithOffset(Error.Message.FileOffset);
+  return diag(Error.DiagnosticName, Loc, Error.Message.Message,
+              static_cast<DiagnosticIDs::Level>(Error.DiagLevel));
+}
+
+DiagnosticBuilder ClangTidyContext::configurationDiag(
+    StringRef Message,
+    DiagnosticIDs::Level Level /* = DiagnosticIDs::Warning*/) {
+  return diag("clang-tidy-config", Message, Level);
+}
+
+void ClangTidyContext::setSourceManager(SourceManager *SourceMgr) {
+  DiagEngine->setSourceManager(SourceMgr);
+}
+
+void ClangTidyContext::setCurrentFile(StringRef File) {
+  CurrentFile = std::string(File);
+  CurrentOptions = getOptionsForFile(CurrentFile);
+  CheckFilter = std::make_unique<CachedGlobList>(*getOptions().Checks);
+  WarningAsErrorFilter =
+      std::make_unique<CachedGlobList>(*getOptions().WarningsAsErrors);
+}
+
+void ClangTidyContext::setASTContext(ASTContext *Context) {
+  DiagEngine->SetArgToStringFn(&FormatASTNodeDiagnosticArgument, Context);
+  LangOpts = Context->getLangOpts();
+}
+
+const ClangTidyGlobalOptions &ClangTidyContext::getGlobalOptions() const {
+  return OptionsProvider->getGlobalOptions();
+}
+
+const ClangTidyOptions &ClangTidyContext::getOptions() const {
+  return CurrentOptions;
+}
+
+ClangTidyOptions ClangTidyContext::getOptionsForFile(StringRef File) const {
+  // Merge options on top of getDefaults() as a safeguard against options with
+  // unset values.
+  return ClangTidyOptions::getDefaults().merge(
+      OptionsProvider->getOptions(File), 0);
+}
+
+void ClangTidyContext::setEnableProfiling(bool P) { Profile = P; }
+
+void ClangTidyContext::setProfileStoragePrefix(StringRef Prefix) {
+  ProfilePrefix = std::string(Prefix);
+}
+
+llvm::Optional<ClangTidyProfiling::StorageParams>
+ClangTidyContext::getProfileStorageParams() const {
+  if (ProfilePrefix.empty())
+    return llvm::None;
+
+  return ClangTidyProfiling::StorageParams(ProfilePrefix, CurrentFile);
+}
+
+bool ClangTidyContext::isCheckEnabled(StringRef CheckName) const {
+  assert(CheckFilter != nullptr);
+  return CheckFilter->contains(CheckName);
+}
+
+bool ClangTidyContext::treatAsError(StringRef CheckName) const {
+  assert(WarningAsErrorFilter != nullptr);
+  return WarningAsErrorFilter->contains(CheckName);
+}
+
+std::string ClangTidyContext::getCheckName(unsigned DiagnosticID) 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 =
+      CheckNamesByDiagnosticID.find(DiagnosticID);
+  if (I != CheckNamesByDiagnosticID.end())
+    return I->second;
+  return "";
+}
+
+} // namespace tidy
+} // namespace clang

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

 //===--- ClangTidyDiagnosticConsumer.h - clang-tidy -------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYDIAGNOSTICCONSUMER_H
 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYDIAGNOSTICCONSUMER_H
 
-#include "ClangTidyOptions.h"
-#include "ClangTidyProfiling.h"
 #include "clang/Basic/Diagnostic.h"
 #include "clang/Tooling/Core/Diagnostic.h"
-#include "llvm/ADT/DenseMap.h"
 #include "llvm/Support/Regex.h"
 
 namespace clang {
 
 class ASTContext;
 class CompilerInstance;
 class SourceManager;
 namespace ast_matchers {
 class MatchFinder;
 } // namespace ast_matchers
 namespace tooling {
 class CompilationDatabase;
 } // namespace tooling
 
 namespace tidy {
-
-/// A detected error complete with information to display diagnostic and
-/// automatic fix.
-///
-/// This is used as an intermediate format to transport Diagnostics without a
-/// dependency on a SourceManager.
-///
-/// FIXME: Make Diagnostics flexible enough to support this directly.
-struct ClangTidyError : tooling::Diagnostic {
-  ClangTidyError(StringRef CheckName, Level DiagLevel, StringRef BuildDirectory,
-                 bool IsWarningAsError);
-
-  bool IsWarningAsError;
-  std::vector<std::string> EnabledDiagnosticAliases;
-};
-
-/// Contains displayed and ignored diagnostic counters for a ClangTidy run.
-struct ClangTidyStats {
-  unsigned ErrorsDisplayed = 0;
-  unsigned ErrorsIgnoredCheckFilter = 0;
-  unsigned ErrorsIgnoredNOLINT = 0;
-  unsigned ErrorsIgnoredNonUserCode = 0;
-  unsigned ErrorsIgnoredLineFilter = 0;
-
-  unsigned errorsIgnored() const {
-    return ErrorsIgnoredNOLINT + ErrorsIgnoredCheckFilter +
-           ErrorsIgnoredNonUserCode + ErrorsIgnoredLineFilter;
-  }
-};
-
-/// Every \c ClangTidyCheck reports errors through a \c DiagnosticsEngine
-/// provided by this context.
-///
-/// A \c ClangTidyCheck always has access to the active context to report
-/// warnings like:
-/// \code
-/// Context->Diag(Loc, "Single-argument constructors must be explicit")
-///     << FixItHint::CreateInsertion(Loc, "explicit ");
-/// \endcode
-class ClangTidyContext {
-public:
-  /// Initializes \c ClangTidyContext instance.
-  ClangTidyContext(std::unique_ptr<ClangTidyOptionsProvider> OptionsProvider,
-                   bool AllowEnablingAnalyzerAlphaCheckers = false);
-  /// Sets the DiagnosticsEngine that diag() will emit diagnostics to.
-  // FIXME: this is required initialization, and should be a constructor param.
-  // Fix the context -> diag engine -> consumer -> context initialization cycle.
-  void setDiagnosticsEngine(DiagnosticsEngine *DiagEngine) {
-    this->DiagEngine = DiagEngine;
-  }
-
-  ~ClangTidyContext();
-
-  /// Report any errors detected using this method.
-  ///
-  /// This is still under heavy development and will likely change towards using
-  /// tablegen'd diagnostic IDs.
-  /// FIXME: Figure out a way to manage ID spaces.
-  DiagnosticBuilder diag(StringRef CheckName, SourceLocation Loc,
-                         StringRef Message,
-                         DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
-
-  DiagnosticBuilder diag(StringRef CheckName, StringRef Message,
-                         DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
-
-  DiagnosticBuilder diag(const ClangTidyError &Error);
-
-  /// Report any errors to do with reading the configuration using this method.
-  DiagnosticBuilder
-  configurationDiag(StringRef Message,
-                    DiagnosticIDs::Level Level = DiagnosticIDs::Warning);
-
-  /// Sets the \c SourceManager of the used \c DiagnosticsEngine.
-  ///
-  /// This is called from the \c ClangTidyCheck base class.
-  void setSourceManager(SourceManager *SourceMgr);
-
-  /// Should be called when starting to process new translation unit.
-  void setCurrentFile(StringRef File);
-
-  /// Returns the main file name of the current translation unit.
-  StringRef getCurrentFile() const { return CurrentFile; }
-
-  /// Sets ASTContext for the current translation unit.
-  void setASTContext(ASTContext *Context);
-
-  /// Gets the language options from the AST context.
-  const LangOptions &getLangOpts() const { return LangOpts; }
-
-  /// Returns the name of the clang-tidy check which produced this
-  /// diagnostic ID.
-  std::string getCheckName(unsigned DiagnosticID) const;
-
-  /// Returns \c true if the check is enabled for the \c CurrentFile.
-  ///
-  /// The \c CurrentFile can be changed using \c setCurrentFile.
-  bool isCheckEnabled(StringRef CheckName) const;
-
-  /// Returns \c true if the check should be upgraded to error for the
-  /// \c CurrentFile.
-  bool treatAsError(StringRef CheckName) const;
-
-  /// Returns global options.
-  const ClangTidyGlobalOptions &getGlobalOptions() const;
-
-  /// Returns options for \c CurrentFile.
-  ///
-  /// The \c CurrentFile can be changed using \c setCurrentFile.
-  const ClangTidyOptions &getOptions() const;
-
-  /// Returns options for \c File. Does not change or depend on
-  /// \c CurrentFile.
-  ClangTidyOptions getOptionsForFile(StringRef File) const;
-
-  /// Returns \c ClangTidyStats containing issued and ignored diagnostic
-  /// counters.
-  const ClangTidyStats &getStats() const { return Stats; }
-
-  /// Control profile collection in clang-tidy.
-  void setEnableProfiling(bool Profile);
-  bool getEnableProfiling() const { return Profile; }
-
-  /// Control storage of profile date.
-  void setProfileStoragePrefix(StringRef ProfilePrefix);
-  llvm::Optional<ClangTidyProfiling::StorageParams>
-  getProfileStorageParams() const;
-
-  /// Should be called when starting to process new translation unit.
-  void setCurrentBuildDirectory(StringRef BuildDirectory) {
-    CurrentBuildDirectory = std::string(BuildDirectory);
-  }
-
-  /// Returns build directory of the current translation unit.
-  const std::string &getCurrentBuildDirectory() const {
-    return CurrentBuildDirectory;
-  }
-
-  /// If the experimental alpha checkers from the static analyzer can be
-  /// enabled.
-  bool canEnableAnalyzerAlphaCheckers() const {
-    return AllowEnablingAnalyzerAlphaCheckers;
-  }
-
-  using DiagLevelAndFormatString = std::pair<DiagnosticIDs::Level, std::string>;
-  DiagLevelAndFormatString getDiagLevelAndFormatString(unsigned DiagnosticID,
-                                                       SourceLocation Loc) {
-    return DiagLevelAndFormatString(
-        static_cast<DiagnosticIDs::Level>(
-            DiagEngine->getDiagnosticLevel(DiagnosticID, Loc)),
-        std::string(
-            DiagEngine->getDiagnosticIDs()->getDescription(DiagnosticID)));
-  }
-
-private:
-  // Writes to Stats.
-  friend class ClangTidyDiagnosticConsumer;
-
-  DiagnosticsEngine *DiagEngine;
-  std::unique_ptr<ClangTidyOptionsProvider> OptionsProvider;
-
-  std::string CurrentFile;
-  ClangTidyOptions CurrentOptions;
-  class CachedGlobList;
-  std::unique_ptr<CachedGlobList> CheckFilter;
-  std::unique_ptr<CachedGlobList> WarningAsErrorFilter;
-
-  LangOptions LangOpts;
-
-  ClangTidyStats Stats;
-
-  std::string CurrentBuildDirectory;
-
-  llvm::DenseMap<unsigned, std::string> CheckNamesByDiagnosticID;
-
-  bool Profile;
-  std::string ProfilePrefix;
-
-  bool AllowEnablingAnalyzerAlphaCheckers;
-};
+class ClangTidyContext;
+struct ClangTidyError;
 
 /// Check whether a given diagnostic should be suppressed due to the presence
 /// of a "NOLINT" suppression comment.
 /// This is exposed so that other tools that present clang-tidy diagnostics
 /// (such as clangd) can respect the same suppression rules as clang-tidy.
 /// This does not handle suppression of notes following a suppressed diagnostic;
 /// that is left to the caller as it requires maintaining state in between calls
 /// to this function.

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

 //===--- tools/extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp ----------=== //
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 ///
-///  \file This file implements ClangTidyDiagnosticConsumer, ClangTidyContext
-///  and ClangTidyError classes.
+///  \file This file implements the ClangTidyDiagnosticConsumer class.
 ///
 ///  This tool uses the Clang Tooling infrastructure, see
 ///    http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
 ///  for details on setting it up with LLVM source tree.
 ///
 //===----------------------------------------------------------------------===//
 
 #include "ClangTidyDiagnosticConsumer.h"
+#include "ClangTidyContext.h"
+#include "ClangTidyError.h"
 #include "ClangTidyOptions.h"
 #include "GlobList.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/ASTDiagnostic.h"
 #include "clang/AST/Attr.h"
 #include "clang/Basic/Diagnostic.h"
 #include "clang/Basic/DiagnosticOptions.h"
 #include "clang/Basic/FileManager.h"
void endDiagnostic(DiagOrStoredDiag D,
     assert(!Error.Message.Message.empty() && "Message has not been set");
   }
 
 private:
   ClangTidyError &Error;
 };
 } // end anonymous namespace
 
-ClangTidyError::ClangTidyError(StringRef CheckName,
-                               ClangTidyError::Level DiagLevel,
-                               StringRef BuildDirectory, bool IsWarningAsError)
-    : tooling::Diagnostic(CheckName, DiagLevel, BuildDirectory),
-      IsWarningAsError(IsWarningAsError) {}
-
-class ClangTidyContext::CachedGlobList {
-public:
-  CachedGlobList(StringRef Globs) : Globs(Globs) {}
-
-  bool contains(StringRef S) {
-    switch (auto &Result = Cache[S]) {
-    case Yes:
-      return true;
-    case No:
-      return false;
-    case None:
-      Result = Globs.contains(S) ? Yes : No;
-      return Result == Yes;
-    }
-    llvm_unreachable("invalid enum");
-  }
-
-private:
-  GlobList Globs;
-  enum Tristate { None, Yes, No };
-  llvm::StringMap<Tristate> Cache;
-};
-
-ClangTidyContext::ClangTidyContext(
-    std::unique_ptr<ClangTidyOptionsProvider> OptionsProvider,
-    bool AllowEnablingAnalyzerAlphaCheckers)
-    : DiagEngine(nullptr), OptionsProvider(std::move(OptionsProvider)),
-      Profile(false),
-      AllowEnablingAnalyzerAlphaCheckers(AllowEnablingAnalyzerAlphaCheckers) {
-  // Before the first translation unit we can get errors related to command-line
-  // parsing, use empty string for the file name in this case.
-  setCurrentFile("");
-}
-
-ClangTidyContext::~ClangTidyContext() = default;
-
-DiagnosticBuilder ClangTidyContext::diag(
-    StringRef CheckName, SourceLocation Loc, StringRef Description,
-    DiagnosticIDs::Level Level /* = DiagnosticIDs::Warning*/) {
-  assert(Loc.isValid());
-  unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
-      Level, (Description + " [" + CheckName + "]").str());
-  CheckNamesByDiagnosticID.try_emplace(ID, CheckName);
-  return DiagEngine->Report(Loc, ID);
-}
-
-DiagnosticBuilder ClangTidyContext::diag(
-    StringRef CheckName, StringRef Description,
-    DiagnosticIDs::Level Level /* = DiagnosticIDs::Warning*/) {
-  unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
-      Level, (Description + " [" + CheckName + "]").str());
-  CheckNamesByDiagnosticID.try_emplace(ID, CheckName);
-  return DiagEngine->Report(ID);
-}
-
-DiagnosticBuilder ClangTidyContext::diag(const ClangTidyError &Error) {
-  SourceManager &SM = DiagEngine->getSourceManager();
-  llvm::ErrorOr<const FileEntry *> File =
-      SM.getFileManager().getFile(Error.Message.FilePath);
-  FileID ID = SM.getOrCreateFileID(*File, SrcMgr::C_User);
-  SourceLocation FileStartLoc = SM.getLocForStartOfFile(ID);
-  SourceLocation Loc = FileStartLoc.getLocWithOffset(Error.Message.FileOffset);
-  return diag(Error.DiagnosticName, Loc, Error.Message.Message,
-              static_cast<DiagnosticIDs::Level>(Error.DiagLevel));
-}
-
-DiagnosticBuilder ClangTidyContext::configurationDiag(
-    StringRef Message,
-    DiagnosticIDs::Level Level /* = DiagnosticIDs::Warning*/) {
-  return diag("clang-tidy-config", Message, Level);
-}
-
-void ClangTidyContext::setSourceManager(SourceManager *SourceMgr) {
-  DiagEngine->setSourceManager(SourceMgr);
-}
-
-void ClangTidyContext::setCurrentFile(StringRef File) {
-  CurrentFile = std::string(File);
-  CurrentOptions = getOptionsForFile(CurrentFile);
-  CheckFilter = std::make_unique<CachedGlobList>(*getOptions().Checks);
-  WarningAsErrorFilter =
-      std::make_unique<CachedGlobList>(*getOptions().WarningsAsErrors);
-}
-
-void ClangTidyContext::setASTContext(ASTContext *Context) {
-  DiagEngine->SetArgToStringFn(&FormatASTNodeDiagnosticArgument, Context);
-  LangOpts = Context->getLangOpts();
-}
-
-const ClangTidyGlobalOptions &ClangTidyContext::getGlobalOptions() const {
-  return OptionsProvider->getGlobalOptions();
-}
-
-const ClangTidyOptions &ClangTidyContext::getOptions() const {
-  return CurrentOptions;
-}
-
-ClangTidyOptions ClangTidyContext::getOptionsForFile(StringRef File) const {
-  // Merge options on top of getDefaults() as a safeguard against options with
-  // unset values.
-  return ClangTidyOptions::getDefaults().merge(
-      OptionsProvider->getOptions(File), 0);
-}
-
-void ClangTidyContext::setEnableProfiling(bool P) { Profile = P; }
-
-void ClangTidyContext::setProfileStoragePrefix(StringRef Prefix) {
-  ProfilePrefix = std::string(Prefix);
-}
-
-llvm::Optional<ClangTidyProfiling::StorageParams>
-ClangTidyContext::getProfileStorageParams() const {
-  if (ProfilePrefix.empty())
-    return llvm::None;
-
-  return ClangTidyProfiling::StorageParams(ProfilePrefix, CurrentFile);
-}
-
-bool ClangTidyContext::isCheckEnabled(StringRef CheckName) const {
-  assert(CheckFilter != nullptr);
-  return CheckFilter->contains(CheckName);
-}
-
-bool ClangTidyContext::treatAsError(StringRef CheckName) const {
-  assert(WarningAsErrorFilter != nullptr);
-  return WarningAsErrorFilter->contains(CheckName);
-}
-
-std::string ClangTidyContext::getCheckName(unsigned DiagnosticID) 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 =
-      CheckNamesByDiagnosticID.find(DiagnosticID);
-  if (I != CheckNamesByDiagnosticID.end())
-    return I->second;
-  return "";
-}
-
 ClangTidyDiagnosticConsumer::ClangTidyDiagnosticConsumer(
     ClangTidyContext &Ctx, DiagnosticsEngine *ExternalDiagEngine,
     bool RemoveIncompatibleErrors, bool GetFixesFromNotes)
     : Context(Ctx), ExternalDiagEngine(ExternalDiagEngine),
       RemoveIncompatibleErrors(RemoveIncompatibleErrors),
       GetFixesFromNotes(GetFixesFromNotes), LastErrorRelatesToUserCode(false),
       LastErrorPassesLineFilter(false), LastErrorWasIgnored(false) {}
 

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

+//===--- ClangTidyError.h - clang-tidy --------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYERROR_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYERROR_H
+
+#include "clang/Tooling/Core/Diagnostic.h"
+#include "llvm/ADT/StringRef.h"
+#include <string>
+#include <vector>
+
+namespace clang {
+namespace tidy {
+
+/// A detected error complete with information to display diagnostic and
+/// automatic fix.
+///
+/// This is used as an intermediate format to transport Diagnostics without a
+/// dependency on a SourceManager.
+///
+/// FIXME: Make Diagnostics flexible enough to support this directly.
+struct ClangTidyError : tooling::Diagnostic {
+  ClangTidyError(StringRef CheckName, Level DiagLevel, StringRef BuildDirectory,
+                 bool IsWarningAsError);
+
+  bool IsWarningAsError;
+  std::vector<std::string> EnabledDiagnosticAliases;
+};
+
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYDIAGNOSTICCONSUMER_H

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

+//===--- tools/extra/clang-tidy/ClangTidyError.cpp -----------------------=== //
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+///  \file This file implements the ClangTidyErrorDiagnosticConsumer class.
+///
+///  This tool uses the Clang Tooling infrastructure, see
+///    http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
+///  for details on setting it up with LLVM source tree.
+///
+//===----------------------------------------------------------------------===//
+
+#include "ClangTidyError.h"
+
+namespace clang {
+namespace tidy {
+
+ClangTidyError::ClangTidyError(StringRef CheckName,
+                               ClangTidyError::Level DiagLevel,
+                               StringRef BuildDirectory, bool IsWarningAsError)
+    : tooling::Diagnostic(CheckName, DiagLevel, BuildDirectory),
+      IsWarningAsError(IsWarningAsError) {}
+
+} // namespace tidy
+} // namespace clang

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

 ///  This tool uses the Clang Tooling infrastructure, see
 ///    http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
 ///  for details on setting it up with LLVM source tree.
 ///
 //===----------------------------------------------------------------------===//
 
 #include "ClangTidyMain.h"
 #include "../ClangTidy.h"
+#include "../ClangTidyContext.h"
+#include "../ClangTidyError.h"
 #include "../ClangTidyForceLinker.h"
 #include "../GlobList.h"
 #include "clang/Tooling/CommonOptionsParser.h"
 #include "llvm/Support/InitLLVM.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Support/WithColor.h"

 Apply suggested fixes even if compilation
 errors were found. If compiler errors have
 attached fix-its, clang-tidy will apply them as
 well.
 )"),
                                cl::init(false), cl::cat(ClangTidyCategory));
 
 static cl::opt<bool> FixNotes("fix-notes", cl::desc(R"(
-If a warning has no fix, but a single fix can 
-be found through an associated diagnostic note, 
-apply the fix. 
-Specifying this flag will implicitly enable the 
+If a warning has no fix, but a single fix can
+be found through an associated diagnostic note,
+apply the fix.
+Specifying this flag will implicitly enable the
 '--fix' flag.
 )"),
                               cl::init(false), cl::cat(ClangTidyCategory));
 
 static cl::opt<std::string> FormatStyle("format-style", cl::desc(R"(
 Style for formatting code around applied fixes:
   - 'none' (default) turns off formatting
   - 'file' (literally 'file', not a placeholder)

clang-tools-extra/unittests/clang-tidy/ClangTidyOptionsTest.cpp

 #include "ClangTidyOptions.h"
 #include "ClangTidyCheck.h"
 #include "ClangTidyDiagnosticConsumer.h"
+#include "ClangTidyError.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/ScopedPrinter.h"
 #include "llvm/Testing/Support/Annotations.h"
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
 
 namespace clang {
 namespace tidy {

clang-tools-extra/unittests/clang-tidy/ClangTidyTest.h

 //===--- ClangTidyTest.h - clang-tidy ---------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_TOOLS_EXTRA_UNITTESTS_CLANG_TIDY_CLANGTIDYTEST_H
 #define LLVM_CLANG_TOOLS_EXTRA_UNITTESTS_CLANG_TIDY_CLANGTIDYTEST_H
 
 #include "ClangTidy.h"
 #include "ClangTidyCheck.h"
 #include "ClangTidyDiagnosticConsumer.h"
+#include "ClangTidyError.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include "clang/Frontend/CompilerInstance.h"
 #include "clang/Frontend/FrontendActions.h"
 #include "clang/Tooling/Core/Diagnostic.h"
 #include "clang/Tooling/Core/Replacement.h"
 #include "clang/Tooling/Refactoring.h"
 #include "clang/Tooling/Tooling.h"
 #include "llvm/Support/Path.h"