clang-tools-extra/clang-tidy/readability/SimplifySubscriptExprCheck.cpp

   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
  22 SimplifySubscriptExprCheck::SimplifySubscriptExprCheck(
  23     StringRef Name, ClangTidyContext *Context)
  24     : ClangTidyCheck(Name, Context), Types(utils::options::parseStringList(
  25                                          Options.get("Types", KDefaultTypes))) {
  26 }
  27
  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
  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
  63 void SimplifySubscriptExprCheck::storeOptions(
  64     ClangTidyOptions::OptionMap &Opts) {
  65   Options.store(Opts, "Types", utils::options::serializeStringList(Types));
  66 }
  67
  68 } // namespace clang::tidy::readability