1//===--- ContainerContainsCheck.cpp - 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#include "ContainerContainsCheck.h"
10#include "clang/AST/ASTContext.h"
11#include "clang/ASTMatchers/ASTMatchFinder.h"
12
13using namespace clang::ast_matchers;
14
15namespace clang::tidy::readability {
16void ContainerContainsCheck::registerMatchers(MatchFinder *Finder) {
17 const auto HasContainsMatchingParamType = hasMethod(
18 InnerMatcher: cxxMethodDecl(isConst(), parameterCountIs(N: 1), returns(InnerMatcher: booleanType()),
19 hasName(Name: "contains"), unless(isDeleted()), isPublic(),
20 hasParameter(N: 0, InnerMatcher: hasType(InnerMatcher: hasUnqualifiedDesugaredType(
21 InnerMatcher: equalsBoundNode(ID: "parameterType"))))));
22
23 const auto CountCall =
24 cxxMemberCallExpr(
25 argumentCountIs(N: 1),
26 callee(InnerMatcher: cxxMethodDecl(
27 hasName(Name: "count"),
28 hasParameter(N: 0, InnerMatcher: hasType(InnerMatcher: hasUnqualifiedDesugaredType(
29 InnerMatcher: type().bind(ID: "parameterType")))),
30 ofClass(InnerMatcher: cxxRecordDecl(HasContainsMatchingParamType)))))
31 .bind(ID: "call");
32
33 const auto FindCall =
34 cxxMemberCallExpr(
35 argumentCountIs(N: 1),
36 callee(InnerMatcher: cxxMethodDecl(
37 hasName(Name: "find"),
38 hasParameter(N: 0, InnerMatcher: hasType(InnerMatcher: hasUnqualifiedDesugaredType(
39 InnerMatcher: type().bind(ID: "parameterType")))),
40 ofClass(InnerMatcher: cxxRecordDecl(HasContainsMatchingParamType)))))
41 .bind(ID: "call");
42
43 const auto EndCall = cxxMemberCallExpr(
44 argumentCountIs(N: 0),
45 callee(
46 InnerMatcher: cxxMethodDecl(hasName(Name: "end"),
47 // In the matchers below, FindCall should always appear
48 // before EndCall so 'parameterType' is properly bound.
49 ofClass(InnerMatcher: cxxRecordDecl(HasContainsMatchingParamType)))));
50
51 const auto Literal0 = integerLiteral(equals(Value: 0));
52 const auto Literal1 = integerLiteral(equals(Value: 1));
53
54 auto AddSimpleMatcher = [&](auto Matcher) {
55 Finder->addMatcher(
56 traverse(TK_IgnoreUnlessSpelledInSource, std::move(Matcher)), this);
57 };
58
59 // Find membership tests which use `count()`.
60 Finder->addMatcher(NodeMatch: implicitCastExpr(hasImplicitDestinationType(InnerMatcher: booleanType()),
61 hasSourceExpression(InnerMatcher: CountCall))
62 .bind(ID: "positiveComparison"),
63 Action: this);
64 AddSimpleMatcher(
65 binaryOperation(hasOperatorName(Name: "!="), hasOperands(Matcher1: CountCall, Matcher2: Literal0))
66 .bind(ID: "positiveComparison"));
67 AddSimpleMatcher(
68 binaryOperation(hasLHS(InnerMatcher: CountCall), hasOperatorName(Name: ">"), hasRHS(InnerMatcher: Literal0))
69 .bind(ID: "positiveComparison"));
70 AddSimpleMatcher(
71 binaryOperation(hasLHS(InnerMatcher: Literal0), hasOperatorName(Name: "<"), hasRHS(InnerMatcher: CountCall))
72 .bind(ID: "positiveComparison"));
73 AddSimpleMatcher(binaryOperation(hasLHS(InnerMatcher: CountCall), hasOperatorName(Name: ">="),
74 hasRHS(InnerMatcher: Literal1))
75 .bind(ID: "positiveComparison"));
76 AddSimpleMatcher(binaryOperation(hasLHS(InnerMatcher: Literal1), hasOperatorName(Name: "<="),
77 hasRHS(InnerMatcher: CountCall))
78 .bind(ID: "positiveComparison"));
79
80 // Find inverted membership tests which use `count()`.
81 AddSimpleMatcher(
82 binaryOperation(hasOperatorName(Name: "=="), hasOperands(Matcher1: CountCall, Matcher2: Literal0))
83 .bind(ID: "negativeComparison"));
84 AddSimpleMatcher(binaryOperation(hasLHS(InnerMatcher: CountCall), hasOperatorName(Name: "<="),
85 hasRHS(InnerMatcher: Literal0))
86 .bind(ID: "negativeComparison"));
87 AddSimpleMatcher(binaryOperation(hasLHS(InnerMatcher: Literal0), hasOperatorName(Name: ">="),
88 hasRHS(InnerMatcher: CountCall))
89 .bind(ID: "negativeComparison"));
90 AddSimpleMatcher(
91 binaryOperation(hasLHS(InnerMatcher: CountCall), hasOperatorName(Name: "<"), hasRHS(InnerMatcher: Literal1))
92 .bind(ID: "negativeComparison"));
93 AddSimpleMatcher(
94 binaryOperation(hasLHS(InnerMatcher: Literal1), hasOperatorName(Name: ">"), hasRHS(InnerMatcher: CountCall))
95 .bind(ID: "negativeComparison"));
96
97 // Find membership tests based on `find() == end()`.
98 AddSimpleMatcher(
99 binaryOperation(hasOperatorName(Name: "!="), hasOperands(Matcher1: FindCall, Matcher2: EndCall))
100 .bind(ID: "positiveComparison"));
101 AddSimpleMatcher(
102 binaryOperation(hasOperatorName(Name: "=="), hasOperands(Matcher1: FindCall, Matcher2: EndCall))
103 .bind(ID: "negativeComparison"));
104}
105
106void ContainerContainsCheck::check(const MatchFinder::MatchResult &Result) {
107 // Extract the information about the match
108 const auto *Call = Result.Nodes.getNodeAs<CXXMemberCallExpr>(ID: "call");
109 const auto *PositiveComparison =
110 Result.Nodes.getNodeAs<Expr>(ID: "positiveComparison");
111 const auto *NegativeComparison =
112 Result.Nodes.getNodeAs<Expr>(ID: "negativeComparison");
113 assert((!PositiveComparison || !NegativeComparison) &&
114 "only one of PositiveComparison or NegativeComparison should be set");
115 bool Negated = NegativeComparison != nullptr;
116 const auto *Comparison = Negated ? NegativeComparison : PositiveComparison;
117
118 // Diagnose the issue.
119 auto Diag =
120 diag(Loc: Call->getExprLoc(), Description: "use 'contains' to check for membership");
121
122 // Don't fix it if it's in a macro invocation. Leave fixing it to the user.
123 SourceLocation FuncCallLoc = Comparison->getEndLoc();
124 if (!FuncCallLoc.isValid() || FuncCallLoc.isMacroID())
125 return;
126
127 // Create the fix it.
128 const auto *Member = cast<MemberExpr>(Call->getCallee());
129 Diag << FixItHint::CreateReplacement(
130 Member->getMemberNameInfo().getSourceRange(), "contains");
131 SourceLocation ComparisonBegin = Comparison->getSourceRange().getBegin();
132 SourceLocation ComparisonEnd = Comparison->getSourceRange().getEnd();
133 SourceLocation CallBegin = Call->getSourceRange().getBegin();
134 SourceLocation CallEnd = Call->getSourceRange().getEnd();
135 Diag << FixItHint::CreateReplacement(
136 RemoveRange: CharSourceRange::getCharRange(B: ComparisonBegin, E: CallBegin),
137 Code: Negated ? "!" : "");
138 Diag << FixItHint::CreateRemoval(RemoveRange: CharSourceRange::getTokenRange(
139 B: CallEnd.getLocWithOffset(Offset: 1), E: ComparisonEnd));
140}
141
142} // namespace clang::tidy::readability
143

source code of clang-tools-extra/clang-tidy/readability/ContainerContainsCheck.cpp