1//===--- MisplacedArrayIndexCheck.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 "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 NodeMatch: traverse(TK: TK_AsIs, InnerMatcher: arraySubscriptExpr(hasLHS(InnerMatcher: hasType(InnerMatcher: isInteger())),
22 hasRHS(InnerMatcher: hasType(InnerMatcher: isAnyPointer())))
23 .bind(ID: "expr")),
24 Action: this);
25}
26
27void MisplacedArrayIndexCheck::check(const MatchFinder::MatchResult &Result) {
28 const auto *ArraySubscriptE =
29 Result.Nodes.getNodeAs<ArraySubscriptExpr>(ID: "expr");
30
31 auto Diag = diag(Loc: ArraySubscriptE->getBeginLoc(), Description: "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 changing
36 // the logic.
37 const Expr *RHSE = ArraySubscriptE->getRHS()->IgnoreParenImpCasts();
38 if (!isa<StringLiteral>(Val: RHSE) && !isa<DeclRefExpr>(Val: RHSE) &&
39 !isa<MemberExpr>(Val: 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::readability
54

source code of clang-tools-extra/clang-tidy/readability/MisplacedArrayIndexCheck.cpp