blob: f11a7d1c6117a588360a3d81e6d1795c8482e45b [file] [log] [blame]
//===--- UsingNamespaceDirectiveCheck.cpp - clang-tidy ----------*- C++ -*-===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "UsingNamespaceDirectiveCheck.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/ASTMatchers/ASTMatchers.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
namespace google {
namespace build {
void UsingNamespaceDirectiveCheck::registerMatchers(
ast_matchers::MatchFinder *Finder) {
// Only register the matchers for C++; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (getLangOpts().CPlusPlus)
Finder->addMatcher(usingDirectiveDecl().bind("usingNamespace"), this);
void UsingNamespaceDirectiveCheck::check(
const MatchFinder::MatchResult &Result) {
const auto *U = Result.Nodes.getNodeAs<UsingDirectiveDecl>("usingNamespace");
SourceLocation Loc = U->getBeginLoc();
if (U->isImplicit() || !Loc.isValid())
// Do not warn if namespace is a std namespace with user-defined literals. The
// user-defined literals can only be used with a using directive.
if (isStdLiteralsNamespace(U->getNominatedNamespace()))
diag(Loc, "do not use namespace using-directives; "
"use using-declarations instead");
// TODO: We could suggest a list of using directives replacing the using
// namespace directive.
bool UsingNamespaceDirectiveCheck::isStdLiteralsNamespace(
const NamespaceDecl *NS) {
if (!NS->getName().endswith("literals"))
return false;
const auto *Parent = dyn_cast_or_null<NamespaceDecl>(NS->getParent());
if (!Parent)
return false;
if (Parent->isStdNamespace())
return true;
return Parent->getName() == "literals" && Parent->getParent() &&
} // namespace build
} // namespace google
} // namespace tidy
} // namespace clang