llvm-project/clang-tools-extra/clang-tidy/readability/RedundantDeclarationCheck.cpp

70 lines
2.2 KiB
C++

//===--- RedundantDeclarationCheck.cpp - clang-tidy------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "RedundantDeclarationCheck.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/Lex/Lexer.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
namespace readability {
void RedundantDeclarationCheck::registerMatchers(MatchFinder *Finder) {
auto UnlessDefinition = unless(isDefinition());
Finder->addMatcher(namedDecl(anyOf(varDecl(UnlessDefinition),
functionDecl(UnlessDefinition)))
.bind("Decl"),
this);
}
void RedundantDeclarationCheck::check(const MatchFinder::MatchResult &Result) {
const auto *D = Result.Nodes.getNodeAs<NamedDecl>("Decl");
const auto *Prev = D->getPreviousDecl();
if (!Prev)
return;
if (!Prev->getLocation().isValid())
return;
if (Prev->getLocation() == D->getLocation())
return;
const SourceManager &SM = *Result.SourceManager;
const bool DifferentHeaders =
!SM.isInMainFile(D->getLocation()) &&
!SM.isWrittenInSameFile(Prev->getLocation(), D->getLocation());
bool MultiVar = false;
if (const auto *VD = dyn_cast<VarDecl>(D)) {
// Is this a multivariable declaration?
for (const auto Other : VD->getDeclContext()->decls()) {
if (Other != D && Other->getLocStart() == VD->getLocStart()) {
MultiVar = true;
break;
}
}
}
SourceLocation EndLoc = Lexer::getLocForEndOfToken(
D->getSourceRange().getEnd(), 0, SM, Result.Context->getLangOpts());
{
auto Diag = diag(D->getLocation(), "redundant %0 declaration") << D;
if (!MultiVar && !DifferentHeaders)
Diag << FixItHint::CreateRemoval(
SourceRange(D->getSourceRange().getBegin(), EndLoc));
}
diag(Prev->getLocation(), "previously declared here", DiagnosticIDs::Note);
}
} // namespace readability
} // namespace tidy
} // namespace clang