xref: /llvm-project/clang-tools-extra/clang-tidy/utils/Matchers.h (revision 0b8866d15ac5806a980d2ff2ea63240d8acfa778)
1 //===--- Matchers.h - clang-tidy-------------------------------------------===//
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_UTILS_MATCHERS_H
10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_MATCHERS_H
11 
12 #include "TypeTraits.h"
13 #include "clang/AST/ExprConcepts.h"
14 #include "clang/ASTMatchers/ASTMatchers.h"
15 #include <optional>
16 
17 namespace clang::tidy::matchers {
18 
19 AST_MATCHER(BinaryOperator, isRelationalOperator) {
20   return Node.isRelationalOp();
21 }
22 
23 AST_MATCHER(BinaryOperator, isEqualityOperator) { return Node.isEqualityOp(); }
24 
25 AST_MATCHER(QualType, isExpensiveToCopy) {
26   std::optional<bool> IsExpensive =
27       utils::type_traits::isExpensiveToCopy(Node, Finder->getASTContext());
28   return IsExpensive && *IsExpensive;
29 }
30 
31 AST_MATCHER(RecordDecl, isTriviallyDefaultConstructible) {
32   return utils::type_traits::recordIsTriviallyDefaultConstructible(
33       Node, Finder->getASTContext());
34 }
35 
36 AST_MATCHER(QualType, isTriviallyDestructible) {
37   return utils::type_traits::isTriviallyDestructible(Node);
38 }
39 
40 // Returns QualType matcher for references to const.
41 AST_MATCHER_FUNCTION(ast_matchers::TypeMatcher, isReferenceToConst) {
42   using namespace ast_matchers;
43   return referenceType(pointee(qualType(isConstQualified())));
44 }
45 
46 // Returns QualType matcher for pointers to const.
47 AST_MATCHER_FUNCTION(ast_matchers::TypeMatcher, isPointerToConst) {
48   using namespace ast_matchers;
49   return pointerType(pointee(qualType(isConstQualified())));
50 }
51 
52 // Returns QualType matcher for target char type only.
53 AST_MATCHER(QualType, isSimpleChar) {
54   const auto ActualType = Node.getTypePtr();
55   return ActualType &&
56          (ActualType->isSpecificBuiltinType(BuiltinType::Char_S) ||
57           ActualType->isSpecificBuiltinType(BuiltinType::Char_U));
58 }
59 
60 AST_MATCHER(Expr, hasUnevaluatedContext) {
61   if (isa<CXXNoexceptExpr>(Node) || isa<RequiresExpr>(Node))
62     return true;
63   if (const auto *UnaryExpr = dyn_cast<UnaryExprOrTypeTraitExpr>(&Node)) {
64     switch (UnaryExpr->getKind()) {
65     case UETT_SizeOf:
66     case UETT_AlignOf:
67       return true;
68     default:
69       return false;
70     }
71   }
72   if (const auto *TypeIDExpr = dyn_cast<CXXTypeidExpr>(&Node))
73     return !TypeIDExpr->isPotentiallyEvaluated();
74   return false;
75 }
76 
77 // A matcher implementation that matches a list of type name regular expressions
78 // against a NamedDecl. If a regular expression contains the substring "::"
79 // matching will occur against the qualified name, otherwise only the typename.
80 class MatchesAnyListedNameMatcher
81     : public ast_matchers::internal::MatcherInterface<NamedDecl> {
82 public:
83   explicit MatchesAnyListedNameMatcher(llvm::ArrayRef<StringRef> NameList) {
84     std::transform(
85         NameList.begin(), NameList.end(), std::back_inserter(NameMatchers),
86         [](const llvm::StringRef Name) { return NameMatcher(Name); });
87   }
88 
89   class NameMatcher {
90     llvm::Regex Regex;
91     enum class MatchMode {
92       // Match against the unqualified name because the regular expression
93       // does not contain ":".
94       MatchUnqualified,
95       // Match against the qualified name because the regular expression
96       // contains ":" suggesting name and namespace should be matched.
97       MatchQualified,
98       // Match against the fully qualified name because the regular expression
99       // starts with ":".
100       MatchFullyQualified,
101     };
102     MatchMode Mode;
103 
104   public:
105     NameMatcher(const llvm::StringRef Regex)
106         : Regex(Regex), Mode(determineMatchMode(Regex)) {}
107 
108     bool match(const NamedDecl &ND) const {
109       switch (Mode) {
110       case MatchMode::MatchQualified:
111         return Regex.match(ND.getQualifiedNameAsString());
112       case MatchMode::MatchFullyQualified:
113         return Regex.match("::" + ND.getQualifiedNameAsString());
114       default:
115         if (const IdentifierInfo *II = ND.getIdentifier())
116           return Regex.match(II->getName());
117         return false;
118       }
119     }
120 
121   private:
122     MatchMode determineMatchMode(llvm::StringRef Regex) {
123       if (Regex.starts_with(":") || Regex.starts_with("^:")) {
124         return MatchMode::MatchFullyQualified;
125       }
126       return Regex.contains(":") ? MatchMode::MatchQualified
127                                  : MatchMode::MatchUnqualified;
128     }
129   };
130 
131   bool matches(
132       const NamedDecl &Node, ast_matchers::internal::ASTMatchFinder *Finder,
133       ast_matchers::internal::BoundNodesTreeBuilder *Builder) const override {
134     return llvm::any_of(NameMatchers, [&Node](const NameMatcher &NM) {
135       return NM.match(Node);
136     });
137   }
138 
139 private:
140   std::vector<NameMatcher> NameMatchers;
141 };
142 
143 // Returns a matcher that matches NamedDecl's against a list of provided regular
144 // expressions. If a regular expression contains starts ':' the NamedDecl's
145 // qualified name will be used for matching, otherwise its name will be used.
146 inline ::clang::ast_matchers::internal::Matcher<NamedDecl>
147 matchesAnyListedName(llvm::ArrayRef<StringRef> NameList) {
148   return ::clang::ast_matchers::internal::makeMatcher(
149       new MatchesAnyListedNameMatcher(NameList));
150 }
151 
152 // Predicate that verify if statement is not identical to one bound to ID node.
153 struct NotIdenticalStatementsPredicate {
154   bool
155   operator()(const clang::ast_matchers::internal::BoundNodesMap &Nodes) const;
156 
157   std::string ID;
158   ::clang::DynTypedNode Node;
159   ASTContext *Context;
160 };
161 
162 // Checks if statement is identical (utils::areStatementsIdentical) to one bound
163 // to ID node.
164 AST_MATCHER_P(Stmt, isStatementIdenticalToBoundNode, std::string, ID) {
165   NotIdenticalStatementsPredicate Predicate{
166       ID, ::clang::DynTypedNode::create(Node), &(Finder->getASTContext())};
167   return Builder->removeBindings(Predicate);
168 }
169 
170 // A matcher implementation that matches a list of type name regular expressions
171 // against a QualType.
172 class MatchesAnyListedTypeNameMatcher
173     : public ast_matchers::internal::MatcherInterface<QualType> {
174 public:
175   explicit MatchesAnyListedTypeNameMatcher(llvm::ArrayRef<StringRef> NameList);
176   ~MatchesAnyListedTypeNameMatcher() override;
177   bool matches(
178       const QualType &Node, ast_matchers::internal::ASTMatchFinder *Finder,
179       ast_matchers::internal::BoundNodesTreeBuilder *Builder) const override;
180 
181 private:
182   std::vector<llvm::Regex> NameMatchers;
183 };
184 
185 // Returns a matcher that matches QualType against a list of provided regular.
186 inline ::clang::ast_matchers::internal::Matcher<QualType>
187 matchesAnyListedTypeName(llvm::ArrayRef<StringRef> NameList) {
188   return ::clang::ast_matchers::internal::makeMatcher(
189       new MatchesAnyListedTypeNameMatcher(NameList));
190 }
191 
192 } // namespace clang::tidy::matchers
193 
194 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_MATCHERS_H
195