clang-tools-extra/clang-tidy/bugprone/InaccurateEraseCheck.cpp

   1 //===--- InaccurateEraseCheck.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 "InaccurateEraseCheck.h"
  10 #include "clang/AST/ASTContext.h"
  11 #include "clang/ASTMatchers/ASTMatchFinder.h"
  12 #include "clang/Lex/Lexer.h"
  13
  14 using namespace clang::ast_matchers;
  15
  16 namespace clang::tidy::bugprone {
  17
  18 void InaccurateEraseCheck::registerMatchers(MatchFinder *Finder) {
  19   const auto EndCall =
  20       callExpr(
  21           callee(functionDecl(hasAnyName("remove", "remove_if", "unique"))),
  22           hasArgument(
  23               1, optionally(cxxMemberCallExpr(callee(cxxMethodDecl(hasName("end"))))
  24                            .bind("end"))))
  25           .bind("alg");
  26
  27   const auto DeclInStd = type(hasUnqualifiedDesugaredType(
  28       tagType(hasDeclaration(decl(isInStdNamespace())))));
  29   Finder->addMatcher(
  30       cxxMemberCallExpr(
  31           on(anyOf(hasType(DeclInStd), hasType(pointsTo(DeclInStd)))),
  32           callee(cxxMethodDecl(hasName("erase"))), argumentCountIs(1),
  33           hasArgument(0, EndCall))
  34           .bind("erase"),
  35       this);
  36 }
  37
  38 void InaccurateEraseCheck::check(const MatchFinder::MatchResult &Result) {
  39   const auto *MemberCall =
  40       Result.Nodes.getNodeAs<CXXMemberCallExpr>("erase");
  41   const auto *EndExpr =
  42       Result.Nodes.getNodeAs<CXXMemberCallExpr>("end");
  43   const SourceLocation Loc = MemberCall->getBeginLoc();
  44
  45   FixItHint Hint;
  46
  47   if (!Loc.isMacroID() && EndExpr) {
  48     const auto *AlgCall = Result.Nodes.getNodeAs<CallExpr>("alg");
  49     std::string ReplacementText = std::string(Lexer::getSourceText(
  50         CharSourceRange::getTokenRange(EndExpr->getSourceRange()),
  51         *Result.SourceManager, getLangOpts()));
  52     const SourceLocation EndLoc = Lexer::getLocForEndOfToken(
  53         AlgCall->getEndLoc(), 0, *Result.SourceManager, getLangOpts());
  54     Hint = FixItHint::CreateInsertion(EndLoc, ", " + ReplacementText);
  55   }
  56
  57   diag(Loc, "this call will remove at most one item even when multiple items "
  58             "should be removed")
  59       << Hint;
  60 }
  61
  62 } // namespace clang::tidy::bugprone