96 lines · cpp
1//===----------------------------------------------------------------------===//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-exception6//7//===----------------------------------------------------------------------===//8 9#include "StringCompareCheck.h"10#include "../utils/OptionsUtils.h"11#include "clang/AST/ASTContext.h"12#include "clang/ASTMatchers/ASTMatchFinder.h"13#include "clang/ASTMatchers/ASTMatchers.h"14#include "clang/Tooling/FixIt.h"15#include "llvm/ADT/StringRef.h"16 17using namespace clang::ast_matchers;18namespace optutils = clang::tidy::utils::options;19 20namespace clang::tidy::readability {21 22static const StringRef CompareMessage = "do not use 'compare' to test equality "23 "of strings; use the string equality "24 "operator instead";25 26static const StringRef DefaultStringLikeClasses = "::std::basic_string;"27 "::std::basic_string_view";28 29StringCompareCheck::StringCompareCheck(StringRef Name,30 ClangTidyContext *Context)31 : ClangTidyCheck(Name, Context),32 StringLikeClasses(optutils::parseStringList(33 Options.get("StringLikeClasses", DefaultStringLikeClasses))) {}34 35void StringCompareCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {36 Options.store(Opts, "StringLikeClasses",37 optutils::serializeStringList(StringLikeClasses));38}39 40void StringCompareCheck::registerMatchers(MatchFinder *Finder) {41 if (StringLikeClasses.empty()) {42 return;43 }44 const auto StrCompare = cxxMemberCallExpr(45 callee(cxxMethodDecl(hasName("compare"), ofClass(cxxRecordDecl(hasAnyName(46 StringLikeClasses))))),47 hasArgument(0, expr().bind("str2")), argumentCountIs(1),48 callee(memberExpr().bind("str1")));49 50 // First and second case: cast str.compare(str) to boolean.51 Finder->addMatcher(52 traverse(TK_AsIs,53 implicitCastExpr(hasImplicitDestinationType(booleanType()),54 has(StrCompare))55 .bind("match1")),56 this);57 58 // Third and fourth case: str.compare(str) == 0 and str.compare(str) != 0.59 Finder->addMatcher(60 binaryOperator(hasAnyOperatorName("==", "!="),61 hasOperands(StrCompare.bind("compare"),62 integerLiteral(equals(0)).bind("zero")))63 .bind("match2"),64 this);65}66 67void StringCompareCheck::check(const MatchFinder::MatchResult &Result) {68 if (const auto *Matched = Result.Nodes.getNodeAs<Stmt>("match1")) {69 diag(Matched->getBeginLoc(), CompareMessage);70 return;71 }72 73 if (const auto *Matched = Result.Nodes.getNodeAs<Stmt>("match2")) {74 const ASTContext &Ctx = *Result.Context;75 76 if (const auto *Zero = Result.Nodes.getNodeAs<Stmt>("zero")) {77 const auto *Str1 = Result.Nodes.getNodeAs<MemberExpr>("str1");78 const auto *Str2 = Result.Nodes.getNodeAs<Stmt>("str2");79 const auto *Compare = Result.Nodes.getNodeAs<Stmt>("compare");80 81 auto Diag = diag(Matched->getBeginLoc(), CompareMessage);82 83 if (Str1->isArrow())84 Diag << FixItHint::CreateInsertion(Str1->getBeginLoc(), "*");85 86 Diag << tooling::fixit::createReplacement(*Zero, *Str2, Ctx)87 << tooling::fixit::createReplacement(*Compare, *Str1->getBase(),88 Ctx);89 }90 }91 92 // FIXME: Add fixit to fix the code for case one and two (match1).93}94 95} // namespace clang::tidy::readability96