clang-tools  14.0.0git
UsingNamespaceDirectiveCheck.cpp
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1 //===--- UsingNamespaceDirectiveCheck.cpp - clang-tidy ----------*- C++ -*-===//
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 
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 #include "clang/ASTMatchers/ASTMatchers.h"
13 
14 using namespace clang::ast_matchers;
15 
16 namespace clang {
17 namespace tidy {
18 namespace google {
19 namespace build {
20 
21 void UsingNamespaceDirectiveCheck::registerMatchers(
22  ast_matchers::MatchFinder *Finder) {
23  Finder->addMatcher(usingDirectiveDecl().bind("usingNamespace"), this);
24 }
25 
27  const MatchFinder::MatchResult &Result) {
28  const auto *U = Result.Nodes.getNodeAs<UsingDirectiveDecl>("usingNamespace");
29  SourceLocation Loc = U->getBeginLoc();
30  if (U->isImplicit() || !Loc.isValid())
31  return;
32 
33  // Do not warn if namespace is a std namespace with user-defined literals. The
34  // user-defined literals can only be used with a using directive.
35  if (isStdLiteralsNamespace(U->getNominatedNamespace()))
36  return;
37 
38  diag(Loc, "do not use namespace using-directives; "
39  "use using-declarations instead");
40  // TODO: We could suggest a list of using directives replacing the using
41  // namespace directive.
42 }
43 
44 bool UsingNamespaceDirectiveCheck::isStdLiteralsNamespace(
45  const NamespaceDecl *NS) {
46  if (!NS->getName().endswith("literals"))
47  return false;
48 
49  const auto *Parent = dyn_cast_or_null<NamespaceDecl>(NS->getParent());
50  if (!Parent)
51  return false;
52 
53  if (Parent->isStdNamespace())
54  return true;
55 
56  return Parent->getName() == "literals" && Parent->getParent() &&
57  Parent->getParent()->isStdNamespace();
58 }
59 } // namespace build
60 } // namespace google
61 } // namespace tidy
62 } // namespace clang
Loc
SourceLocation Loc
Definition: KernelNameRestrictionCheck.cpp:45
UsingNamespaceDirectiveCheck.h
clang::ast_matchers
Definition: AbseilMatcher.h:14
clang::clangd::check
bool check(llvm::StringRef File, llvm::function_ref< bool(const Position &)> ShouldCheckLine, const ThreadsafeFS &TFS, const ClangdLSPServer::Options &Opts, bool EnableCodeCompletion)
Definition: Check.cpp:258
Parent
const Node * Parent
Definition: ExtractFunction.cpp:152
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ApplyReplacements.h:27