1 //===--- GlobalNamesInHeadersCheck.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
9 #include "GlobalNamesInHeadersCheck.h"
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 #include "clang/ASTMatchers/ASTMatchers.h"
13 #include "clang/Lex/Lexer.h"
14
15 using namespace clang::ast_matchers;
16
17 namespace clang {
18 namespace tidy {
19 namespace google {
20 namespace readability {
21
GlobalNamesInHeadersCheck(StringRef Name,ClangTidyContext * Context)22 GlobalNamesInHeadersCheck::GlobalNamesInHeadersCheck(StringRef Name,
23 ClangTidyContext *Context)
24 : ClangTidyCheck(Name, Context),
25 RawStringHeaderFileExtensions(Options.getLocalOrGlobal(
26 "HeaderFileExtensions", utils::defaultHeaderFileExtensions())) {
27 if (!utils::parseFileExtensions(RawStringHeaderFileExtensions,
28 HeaderFileExtensions,
29 utils::defaultFileExtensionDelimiters())) {
30 this->configurationDiag("Invalid header file extension: '%0'")
31 << RawStringHeaderFileExtensions;
32 }
33 }
34
storeOptions(ClangTidyOptions::OptionMap & Opts)35 void GlobalNamesInHeadersCheck::storeOptions(
36 ClangTidyOptions::OptionMap &Opts) {
37 Options.store(Opts, "HeaderFileExtensions", RawStringHeaderFileExtensions);
38 }
39
registerMatchers(ast_matchers::MatchFinder * Finder)40 void GlobalNamesInHeadersCheck::registerMatchers(
41 ast_matchers::MatchFinder *Finder) {
42 Finder->addMatcher(decl(anyOf(usingDecl(), usingDirectiveDecl()),
43 hasDeclContext(translationUnitDecl()))
44 .bind("using_decl"),
45 this);
46 }
47
check(const MatchFinder::MatchResult & Result)48 void GlobalNamesInHeadersCheck::check(const MatchFinder::MatchResult &Result) {
49 const auto *D = Result.Nodes.getNodeAs<Decl>("using_decl");
50 // If it comes from a macro, we'll assume it is fine.
51 if (D->getBeginLoc().isMacroID())
52 return;
53
54 // Ignore if it comes from the "main" file ...
55 if (Result.SourceManager->isInMainFile(
56 Result.SourceManager->getExpansionLoc(D->getBeginLoc()))) {
57 // unless that file is a header.
58 if (!utils::isSpellingLocInHeaderFile(
59 D->getBeginLoc(), *Result.SourceManager, HeaderFileExtensions))
60 return;
61 }
62
63 if (const auto *UsingDirective = dyn_cast<UsingDirectiveDecl>(D)) {
64 if (UsingDirective->getNominatedNamespace()->isAnonymousNamespace()) {
65 // Anonymous namespaces inject a using directive into the AST to import
66 // the names into the containing namespace.
67 // We should not have them in headers, but there is another warning for
68 // that.
69 return;
70 }
71 }
72
73 diag(D->getBeginLoc(),
74 "using declarations in the global namespace in headers are prohibited");
75 }
76
77 } // namespace readability
78 } // namespace google
79 } // namespace tidy
80 } // namespace clang
81