clang-tools  3.8.0
GlobalNamesInHeadersCheck.cpp
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1 //===--- GlobalNamesInHeadersCheck.cpp - clang-tidy -----------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 #include "clang/ASTMatchers/ASTMatchers.h"
14 #include "clang/Lex/Lexer.h"
15 
16 using namespace clang::ast_matchers;
17 
18 namespace clang {
19 namespace tidy {
20 namespace google {
21 namespace readability {
22 
23 void
24 GlobalNamesInHeadersCheck::registerMatchers(ast_matchers::MatchFinder *Finder) {
25  Finder->addMatcher(
26  decl(anyOf(usingDecl(), usingDirectiveDecl()),
27  hasDeclContext(translationUnitDecl())).bind("using_decl"),
28  this);
29 }
30 
31 void GlobalNamesInHeadersCheck::check(const MatchFinder::MatchResult &Result) {
32  const auto *D = Result.Nodes.getNodeAs<Decl>("using_decl");
33  // If it comes from a macro, we'll assume it is fine.
34  if (D->getLocStart().isMacroID())
35  return;
36 
37  // Ignore if it comes from the "main" file ...
38  if (Result.SourceManager->isInMainFile(
39  Result.SourceManager->getExpansionLoc(D->getLocStart()))) {
40  // unless that file is a header.
41  StringRef Filename = Result.SourceManager->getFilename(
42  Result.SourceManager->getSpellingLoc(D->getLocStart()));
43 
44  if (!Filename.endswith(".h"))
45  return;
46  }
47 
48  if (const auto* UsingDirective = dyn_cast<UsingDirectiveDecl>(D)) {
49  if (UsingDirective->getNominatedNamespace()->isAnonymousNamespace()) {
50  // Anynoumous namespaces inject a using directive into the AST to import
51  // the names into the containing namespace.
52  // We should not have them in headers, but there is another warning for
53  // that.
54  return;
55  }
56  }
57 
58  diag(D->getLocStart(),
59  "using declarations in the global namespace in headers are prohibited");
60 }
61 
62 } // namespace readability
63 } // namespace google
64 } // namespace tidy
65 } // namespace clang
std::unique_ptr< ast_matchers::MatchFinder > Finder
Definition: ClangTidy.cpp:188
std::string Filename
Filename as a string.
const NamedDecl * Result
Definition: USRFinder.cpp:121