xref: /llvm-project/clang-tools-extra/clang-tidy/cppcoreguidelines/SpecialMemberFunctionsCheck.h (revision 54c6ee922abbaea7d2f138a209f320c414c1657b)
1 //===--- SpecialMemberFunctionsCheck.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_CPPCOREGUIDELINES_SPECIAL_MEMBER_FUNCTIONS_H
10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_SPECIAL_MEMBER_FUNCTIONS_H
11 
12 #include "../ClangTidyCheck.h"
13 
14 #include "llvm/ADT/DenseMapInfo.h"
15 
16 namespace clang::tidy::cppcoreguidelines {
17 
18 /// Checks for classes where some, but not all, of the special member functions
19 /// are defined.
20 ///
21 /// For the user-facing documentation see:
22 /// http://clang.llvm.org/extra/clang-tidy/checks/cppcoreguidelines/special-member-functions.html
23 class SpecialMemberFunctionsCheck : public ClangTidyCheck {
24 public:
25   SpecialMemberFunctionsCheck(StringRef Name, ClangTidyContext *Context);
isLanguageVersionSupported(const LangOptions & LangOpts)26   bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
27     return LangOpts.CPlusPlus;
28   }
29   void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
30   void registerMatchers(ast_matchers::MatchFinder *Finder) override;
31   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
32   void onEndOfTranslationUnit() override;
33   std::optional<TraversalKind> getCheckTraversalKind() const override;
34 
35   enum class SpecialMemberFunctionKind : uint8_t {
36     Destructor,
37     DefaultDestructor,
38     NonDefaultDestructor,
39     CopyConstructor,
40     CopyAssignment,
41     MoveConstructor,
42     MoveAssignment
43   };
44 
45   struct SpecialMemberFunctionData {
46     SpecialMemberFunctionKind FunctionKind;
47     bool IsDeleted;
48     bool IsImplicit = false;
49 
50     bool operator==(const SpecialMemberFunctionData &Other) const {
51       return (Other.FunctionKind == FunctionKind) &&
52              (Other.IsDeleted == IsDeleted);
53     }
54   };
55 
56   using ClassDefId = std::pair<SourceLocation, std::string>;
57 
58   using ClassDefiningSpecialMembersMap =
59       llvm::DenseMap<ClassDefId,
60                      llvm::SmallVector<SpecialMemberFunctionData, 5>>;
61 
62 private:
63   void checkForMissingMembers(
64       const ClassDefId &ID,
65       llvm::ArrayRef<SpecialMemberFunctionData> DefinedMembers);
66 
67   const bool AllowMissingMoveFunctions;
68   const bool AllowSoleDefaultDtor;
69   const bool AllowMissingMoveFunctionsWhenCopyIsDeleted;
70   const bool AllowImplicitlyDeletedCopyOrMove;
71   ClassDefiningSpecialMembersMap ClassWithSpecialMembers;
72 };
73 
74 } // namespace clang::tidy::cppcoreguidelines
75 
76 namespace llvm {
77 /// Specialization of DenseMapInfo to allow ClassDefId objects in DenseMaps
78 /// FIXME: Move this to the corresponding cpp file as is done for
79 /// clang-tidy/readability/IdentifierNamingCheck.cpp.
80 template <>
81 struct DenseMapInfo<
82     clang::tidy::cppcoreguidelines::SpecialMemberFunctionsCheck::ClassDefId> {
83   using ClassDefId =
84       clang::tidy::cppcoreguidelines::SpecialMemberFunctionsCheck::ClassDefId;
85 
86   static inline ClassDefId getEmptyKey() {
87     return {DenseMapInfo<clang::SourceLocation>::getEmptyKey(),
88                       "EMPTY"};
89   }
90 
91   static inline ClassDefId getTombstoneKey() {
92     return {DenseMapInfo<clang::SourceLocation>::getTombstoneKey(),
93                       "TOMBSTONE"};
94   }
95 
96   static unsigned getHashValue(ClassDefId Val) {
97     assert(Val != getEmptyKey() && "Cannot hash the empty key!");
98     assert(Val != getTombstoneKey() && "Cannot hash the tombstone key!");
99 
100     std::hash<ClassDefId::second_type> SecondHash;
101     return Val.first.getHashValue() + SecondHash(Val.second);
102   }
103 
104   static bool isEqual(const ClassDefId &LHS, const ClassDefId &RHS) {
105     if (RHS == getEmptyKey())
106       return LHS == getEmptyKey();
107     if (RHS == getTombstoneKey())
108       return LHS == getTombstoneKey();
109     return LHS == RHS;
110   }
111 };
112 
113 } // namespace llvm
114 
115 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_SPECIAL_MEMBER_FUNCTIONS_H
116