1 //===--- UnusedUsingDeclsCheck.h - clang-tidy--------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MISC_UNUSED_USING_DECLS_H 10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MISC_UNUSED_USING_DECLS_H 11 12 #include "../ClangTidyCheck.h" 13 #include "llvm/ADT/SmallPtrSet.h" 14 #include <vector> 15 16 namespace clang { 17 namespace tidy { 18 namespace misc { 19 20 /// Finds unused using declarations. 21 /// 22 /// For the user-facing documentation see: 23 /// http://clang.llvm.org/extra/clang-tidy/checks/misc-unused-using-decls.html 24 class UnusedUsingDeclsCheck : public ClangTidyCheck { 25 public: UnusedUsingDeclsCheck(StringRef Name,ClangTidyContext * Context)26 UnusedUsingDeclsCheck(StringRef Name, ClangTidyContext *Context) 27 : ClangTidyCheck(Name, Context) {} 28 void registerMatchers(ast_matchers::MatchFinder *Finder) override; 29 void check(const ast_matchers::MatchFinder::MatchResult &Result) override; 30 void onEndOfTranslationUnit() override; 31 32 private: 33 void removeFromFoundDecls(const Decl *D); 34 35 struct UsingDeclContext { UsingDeclContextUsingDeclContext36 explicit UsingDeclContext(const UsingDecl *FoundUsingDecl) 37 : FoundUsingDecl(FoundUsingDecl), IsUsed(false) {} 38 // A set saves all UsingShadowDecls introduced by a UsingDecl. A UsingDecl 39 // can introduce multiple UsingShadowDecls in some cases (such as 40 // overloaded functions). 41 llvm::SmallPtrSet<const Decl *, 4> UsingTargetDecls; 42 // The original UsingDecl. 43 const UsingDecl *FoundUsingDecl; 44 // The source range of the UsingDecl. 45 CharSourceRange UsingDeclRange; 46 // Whether the UsingDecl is used. 47 bool IsUsed; 48 }; 49 50 std::vector<UsingDeclContext> Contexts; 51 }; 52 53 } // namespace misc 54 } // namespace tidy 55 } // namespace clang 56 57 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MISC_UNUSED_USING_DECLS_H 58