1 //===--- StaticDefinitionInAnonymousNamespaceCheck.cpp - clang-tidy--------===//
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 
10 #include "StaticDefinitionInAnonymousNamespaceCheck.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 #include "clang/Lex/Lexer.h"
14 
15 using namespace clang::ast_matchers;
16 
17 namespace clang {
18 namespace tidy {
19 namespace readability {
20 
21 namespace {
22 AST_POLYMORPHIC_MATCHER(isStatic, AST_POLYMORPHIC_SUPPORTED_TYPES(FunctionDecl,
23                                                                   VarDecl)) {
24   return Node.getStorageClass() == SC_Static;
25 }
26 } // namespace
27 
28 void StaticDefinitionInAnonymousNamespaceCheck::registerMatchers(
29     MatchFinder *Finder) {
30   Finder->addMatcher(namedDecl(anyOf(functionDecl(isDefinition(), isStatic()),
31                                      varDecl(isDefinition(), isStatic())),
32                                hasParent(namespaceDecl(isAnonymous())))
33                          .bind("static-def"),
34                      this);
35 }
36 
37 void StaticDefinitionInAnonymousNamespaceCheck::check(
38     const MatchFinder::MatchResult &Result) {
39   const auto *Def = Result.Nodes.getNodeAs<NamedDecl>("static-def");
40   // Skips all static definitions defined in Macro.
41   if (Def->getLocation().isMacroID())
42     return;
43 
44   // Skips all static definitions in function scope.
45   const DeclContext *DC = Def->getDeclContext();
46   if (DC->getDeclKind() != Decl::Namespace)
47     return;
48 
49   auto Diag =
50       diag(Def->getLocation(), "%0 is a static definition in "
51                                "anonymous namespace; static is redundant here")
52       << Def;
53   Token Tok;
54   SourceLocation Loc = Def->getSourceRange().getBegin();
55   while (Loc < Def->getSourceRange().getEnd() &&
56          !Lexer::getRawToken(Loc, Tok, *Result.SourceManager,
57                              Result.Context->getLangOpts(), true)) {
58     SourceRange TokenRange(Tok.getLocation(), Tok.getEndLoc());
59     StringRef SourceText = Lexer::getSourceText(
60         CharSourceRange::getTokenRange(TokenRange),
61         *Result.SourceManager, Result.Context->getLangOpts());
62     if (SourceText == "static") {
63       Diag << FixItHint::CreateRemoval(TokenRange);
64       break;
65     }
66     Loc = Tok.getEndLoc();
67   }
68 }
69 
70 } // namespace readability
71 } // namespace tidy
72 } // namespace clang
73