54 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 "MisplacedArrayIndexCheck.h"10#include "clang/AST/ASTContext.h"11#include "clang/ASTMatchers/ASTMatchFinder.h"12#include "clang/Lex/Lexer.h"13#include "clang/Tooling/FixIt.h"14 15using namespace clang::ast_matchers;16 17namespace clang::tidy::readability {18 19void MisplacedArrayIndexCheck::registerMatchers(MatchFinder *Finder) {20 Finder->addMatcher(21 traverse(TK_AsIs, arraySubscriptExpr(hasLHS(hasType(isInteger())),22 hasRHS(hasType(isAnyPointer())))23 .bind("expr")),24 this);25}26 27void MisplacedArrayIndexCheck::check(const MatchFinder::MatchResult &Result) {28 const auto *ArraySubscriptE =29 Result.Nodes.getNodeAs<ArraySubscriptExpr>("expr");30 31 auto Diag = diag(ArraySubscriptE->getBeginLoc(), "confusing array subscript "32 "expression, usually the "33 "index is inside the []");34 35 // Only try to fixit when LHS and RHS can be swapped directly without changing36 // the logic.37 const Expr *RHSE = ArraySubscriptE->getRHS()->IgnoreParenImpCasts();38 if (!isa<StringLiteral>(RHSE) && !isa<DeclRefExpr>(RHSE) &&39 !isa<MemberExpr>(RHSE))40 return;41 42 const StringRef LText = tooling::fixit::getText(43 ArraySubscriptE->getLHS()->getSourceRange(), *Result.Context);44 const StringRef RText = tooling::fixit::getText(45 ArraySubscriptE->getRHS()->getSourceRange(), *Result.Context);46 47 Diag << FixItHint::CreateReplacement(48 ArraySubscriptE->getLHS()->getSourceRange(), RText);49 Diag << FixItHint::CreateReplacement(50 ArraySubscriptE->getRHS()->getSourceRange(), LText);51}52 53} // namespace clang::tidy::readability54