xref: /llvm-project/clang-tools-extra/clang-tidy/readability/SimplifySubscriptExprCheck.cpp (revision 8c24422cd4a5ec458950e135f62d9b14a96e75cc)
1 //===--- SimplifySubscriptExprCheck.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 "SimplifySubscriptExprCheck.h"
10 #include "../utils/OptionsUtils.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 
14 using namespace clang::ast_matchers;
15 
16 namespace clang::tidy::readability {
17 
18 static const char KDefaultTypes[] =
19     "::std::basic_string;::std::basic_string_view;::std::vector;::std::array;::"
20     "std::span";
21 
SimplifySubscriptExprCheck(StringRef Name,ClangTidyContext * Context)22 SimplifySubscriptExprCheck::SimplifySubscriptExprCheck(
23     StringRef Name, ClangTidyContext *Context)
24     : ClangTidyCheck(Name, Context), Types(utils::options::parseStringList(
25                                          Options.get("Types", KDefaultTypes))) {
26 }
27 
registerMatchers(MatchFinder * Finder)28 void SimplifySubscriptExprCheck::registerMatchers(MatchFinder *Finder) {
29   const auto TypesMatcher = hasUnqualifiedDesugaredType(
30       recordType(hasDeclaration(cxxRecordDecl(hasAnyName(Types)))));
31 
32   Finder->addMatcher(
33       arraySubscriptExpr(hasBase(
34           cxxMemberCallExpr(
35               has(memberExpr().bind("member")),
36               on(hasType(qualType(
37                   unless(anyOf(substTemplateTypeParmType(),
38                                hasDescendant(substTemplateTypeParmType()))),
39                   anyOf(TypesMatcher, pointerType(pointee(TypesMatcher)))))),
40               callee(namedDecl(hasName("data"))))
41               .bind("call"))),
42       this);
43 }
44 
check(const MatchFinder::MatchResult & Result)45 void SimplifySubscriptExprCheck::check(const MatchFinder::MatchResult &Result) {
46   const auto *Call = Result.Nodes.getNodeAs<CXXMemberCallExpr>("call");
47   if (Result.Context->getSourceManager().isMacroBodyExpansion(
48           Call->getExprLoc()))
49     return;
50 
51   const auto *Member = Result.Nodes.getNodeAs<MemberExpr>("member");
52   auto DiagBuilder =
53       diag(Member->getMemberLoc(),
54            "accessing an element of the container does not require a call to "
55            "'data()'; did you mean to use 'operator[]'?");
56   if (Member->isArrow())
57     DiagBuilder << FixItHint::CreateInsertion(Member->getBeginLoc(), "(*")
58                 << FixItHint::CreateInsertion(Member->getOperatorLoc(), ")");
59   DiagBuilder << FixItHint::CreateRemoval(
60       {Member->getOperatorLoc(), Call->getEndLoc()});
61 }
62 
storeOptions(ClangTidyOptions::OptionMap & Opts)63 void SimplifySubscriptExprCheck::storeOptions(
64     ClangTidyOptions::OptionMap &Opts) {
65   Options.store(Opts, "Types", utils::options::serializeStringList(Types));
66 }
67 
68 } // namespace clang::tidy::readability
69