[clang-tools-extra] create new clang-tidy check to add namespaces to symbol references (PR #70621)

[Piotr Zegar via cfe-commits]

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@@ -0,0 +1,64 @@
+//===--- UseExplicitNamespacesCheck.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_READABILITY_USEEXPLICITNAMESPACESCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_USEEXPLICITNAMESPACESCHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang::tidy::readability {
+
+/// FIXME: Write a short description.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/readability/use-explicit-namespaces.html
+class UseExplicitNamespacesCheck : public ClangTidyCheck {
+public:
+  UseExplicitNamespacesCheck(StringRef Name, ClangTidyContext *Context);
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+
+  void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
+  bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
+    return LangOpts.CPlusPlus;
+  }
+
+  IdentifierInfo *
+  getTypeNestedNameIdentfierRecursive(const Type *type,
+                                      std::string &nestedTypeInfo);
+  bool matchesNamespaceLimits(
+      const std::vector<const DeclContext *> &targetContextVector);
+
+  void diagOut(const SourceLocation &sourcePosition,
+               const std::string &message);
+
+  void processTransform(NestedNameSpecifierLoc nestedName,
+                        const SourceLocation &sourcePosition,
+                        const NamedDecl *target,
+                        const DeclContext *referenceContext, bool usingShadow,
+                        const std::string &context);
+
+  void processTypePiecesRecursive(NestedNameSpecifierLoc nestedName,
+                                  const TypeLoc &typeLoc,
+                                  const DeclContext *declContext,
+                                  const std::string &context);
+
+  void processTypePieces(TypeSourceInfo *typeSourceInfo,
+                         const DeclContext *declContext,
+                         const std::string &context);
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PiotrZSL wrote:

Make all those methods private, and if they not needed make them non-class members private methods in .cpp

https://github.com/llvm/llvm-project/pull/70621