[clang-tidy][NFC] Use C++17 nested namespaces in clang-tidy headers

We forgot to apply the change to headers in the previous patch,
due to missing "-header-filter" in the run-clang-tidy invocation.

Differential Revision: https://reviews.llvm.org/D142307

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

@@ -12,8 +12,7 @@
 #include "clang-tidy-config.h"
 #include "llvm/Support/Compiler.h"
 
-namespace clang {
-namespace tidy {
+namespace clang::tidy {
 
 // This anchor is used to force the linker to link the AbseilModule.
 extern volatile int AbseilModuleAnchorSource;
@@ -138,7 +137,6 @@ extern volatile int ZirconModuleAnchorSource;
 static int LLVM_ATTRIBUTE_UNUSED ZirconModuleAnchorDestination =
     ZirconModuleAnchorSource;
 
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy
 
 #endif

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

@@ -15,8 +15,7 @@
 #include <functional>
 #include <memory>
 
-namespace clang {
-namespace tidy {
+namespace clang::tidy {
 
 class ClangTidyCheck;
 class ClangTidyContext;
@@ -94,7 +93,6 @@ class ClangTidyModule {
   virtual ClangTidyOptions getModuleOptions();
 };
 
-} // end namespace tidy
-} // end namespace clang
+} // namespace clang::tidy
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYMODULE_H

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

@@ -12,12 +12,10 @@
 #include "ClangTidyModule.h"
 #include "llvm/Support/Registry.h"
 
-namespace clang {
-namespace tidy {
+namespace clang::tidy {
 
 typedef llvm::Registry<ClangTidyModule> ClangTidyModuleRegistry;
 
-} // end namespace tidy
-} // end namespace clang
+} // namespace clang::tidy
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYMODULEREGISTRY_H

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

@@ -22,8 +22,7 @@
 #include <utility>
 #include <vector>
 
-namespace clang {
-namespace tidy {
+namespace clang::tidy {
 
 /// Contains a list of line ranges in a single file.
 struct FileFilter {
@@ -328,7 +327,6 @@ parseConfigurationWithDiags(llvm::MemoryBufferRef Config, DiagCallback Handler);
 /// Serializes configuration to a YAML-encoded string.
 std::string configurationAsText(const ClangTidyOptions &Options);
 
-} // end namespace tidy
-} // end namespace clang
+} // namespace clang::tidy
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYOPTIONS_H

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

@@ -19,8 +19,7 @@ namespace llvm {
 class raw_ostream;
 } // namespace llvm
 
-namespace clang {
-namespace tidy {
+namespace clang::tidy {
 
 class ClangTidyProfiling {
 public:
@@ -54,7 +53,6 @@ class ClangTidyProfiling {
   ~ClangTidyProfiling();
 };
 
-} // end namespace tidy
-} // end namespace clang
+} // namespace clang::tidy
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYPROFILING_H

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

@@ -13,12 +13,10 @@
 #include "clang/Lex/Preprocessor.h"
 #include "llvm/ADT/DenseSet.h"
 
-namespace llvm {
-namespace vfs {
+namespace llvm::vfs {
 class OverlayFileSystem;
 class InMemoryFileSystem;
-} // namespace vfs
-} // namespace llvm
+} // namespace llvm::vfs
 
 namespace clang {
 class CompilerInstance;

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

@@ -15,8 +15,7 @@
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Regex.h"
 
-namespace clang {
-namespace tidy {
+namespace clang::tidy {
 
 /// Read-only set of strings represented as a list of positive and negative
 /// globs.
@@ -62,7 +61,6 @@ class CachedGlobList final : public GlobList {
   mutable llvm::StringMap<bool> Cache;
 };
 
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GLOBLIST_H

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

@@ -13,18 +13,15 @@
 #include "llvm/ADT/StringRef.h"
 #include <memory>
 
-namespace clang {
-namespace tooling {
+namespace clang::tooling {
 struct Diagnostic;
-} // namespace tooling
-} // namespace clang
+} // namespace clang::tooling
 
 namespace llvm {
 template <typename T> class SmallVectorImpl;
 } // namespace llvm
 
-namespace clang {
-namespace tidy {
+namespace clang::tidy {
 
 /// This class is used to locate NOLINT comments in the file being analyzed, to
 /// decide whether a diagnostic should be suppressed.
@@ -45,7 +42,6 @@ class NoLintDirectiveHandler {
   std::unique_ptr<Impl> PImpl;
 };
 
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_NOLINTDIRECTIVEHANDLER_H

clang-tools-extra/clang-tidy/abseil/AbseilMatcher.h

@@ -10,8 +10,7 @@
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include <algorithm>
 
-namespace clang {
-namespace ast_matchers {
+namespace clang::ast_matchers {
 
 /// Matches AST nodes that were found within Abseil files.
 ///
@@ -57,5 +56,4 @@ AST_POLYMORPHIC_MATCHER(
   });
 }
 
-} // namespace ast_matchers
-} // namespace clang
+} // namespace clang::ast_matchers

clang-tools-extra/clang-tidy/abseil/CleanupCtadCheck.h

@@ -11,9 +11,7 @@
 
 #include "../utils/TransformerClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// Suggests switching the initialization pattern of `absl::Cleanup`
 /// instances from the factory function to class template argument
@@ -30,8 +28,6 @@ class CleanupCtadCheck : public utils::TransformerClangTidyCheck {
   }
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_CLEANUPCTADCHECK_H

clang-tools-extra/clang-tidy/abseil/DurationAdditionCheck.h

@@ -11,9 +11,7 @@
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// Checks for cases where addition should be performed in the
 /// ``absl::Time`` domain.
@@ -28,8 +26,6 @@ class DurationAdditionCheck : public ClangTidyCheck {
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_TIMEADDITIONCHECK_H

clang-tools-extra/clang-tidy/abseil/DurationComparisonCheck.h

@@ -11,9 +11,7 @@
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// Prefer comparison in the absl::Duration domain instead of the numeric
 /// domain.
@@ -28,8 +26,6 @@ class DurationComparisonCheck : public ClangTidyCheck {
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_DURATIONCOMPARISONCHECK_H

clang-tools-extra/clang-tidy/abseil/DurationConversionCastCheck.h

@@ -11,9 +11,7 @@
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// Checks for casts of ``absl::Duration`` conversion functions, and recommends
 /// the right conversion function instead.
@@ -28,8 +26,6 @@ class DurationConversionCastCheck : public ClangTidyCheck {
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_DURATIONCONVERSIONCASTCHECK_H

clang-tools-extra/clang-tidy/abseil/DurationDivisionCheck.h

@@ -11,9 +11,7 @@
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 // Find potential incorrect uses of integer division of absl::Duration objects.
 //
@@ -30,8 +28,6 @@ class DurationDivisionCheck : public ClangTidyCheck {
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_DURATIONDIVISIONCHECK_H_

clang-tools-extra/clang-tidy/abseil/DurationFactoryFloatCheck.h

@@ -11,9 +11,7 @@
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// This check finds cases where `Duration` factories are being called with
 /// floating point arguments, but could be called using integer arguments.
@@ -30,8 +28,6 @@ class DurationFactoryFloatCheck : public ClangTidyCheck {
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_DURATIONFACTORYFLOATCHECK_H

clang-tools-extra/clang-tidy/abseil/DurationFactoryScaleCheck.h

@@ -11,9 +11,7 @@
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// This check finds cases where the incorrect `Duration` factory function is
 /// being used by looking for scaling constants inside the factory argument
@@ -30,8 +28,6 @@ class DurationFactoryScaleCheck : public ClangTidyCheck {
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_DURATIONFACTORYSCALECHECK_H

clang-tools-extra/clang-tidy/abseil/DurationRewriter.h

@@ -14,9 +14,7 @@
 #include <cinttypes>
 #include <optional>
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// Duration factory and conversion scales
 enum class DurationScale : std::uint8_t {
@@ -135,8 +133,6 @@ AST_MATCHER_FUNCTION_P(ast_matchers::internal::Matcher<Stmt>,
       hasEitherOperand(ignoringImpCasts(callExpr(callee(funcDecl)))));
 }
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_DURATIONREWRITER_H

clang-tools-extra/clang-tidy/abseil/DurationSubtractionCheck.h

@@ -11,9 +11,7 @@
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// Checks for cases where subtraction should be performed in the
 /// `absl::Duration` domain.
@@ -28,8 +26,6 @@ class DurationSubtractionCheck : public ClangTidyCheck {
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_DURATIONSUBTRACTIONCHECK_H

clang-tools-extra/clang-tidy/abseil/DurationUnnecessaryConversionCheck.h

@@ -11,9 +11,7 @@
 
 #include "../ClangTidyCheck.h"
 
-namespace clang {
-namespace tidy {
-namespace abseil {
+namespace clang::tidy::abseil {
 
 /// Finds and fixes cases where ``absl::Duration`` values are being converted
 /// to numeric types and back again.
@@ -28,8 +26,6 @@ class DurationUnnecessaryConversionCheck : public ClangTidyCheck {
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };
 
-} // namespace abseil
-} // namespace tidy
-} // namespace clang
+} // namespace clang::tidy::abseil
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ABSEIL_TIMEDOUBLECONVERSIONCHECK_H