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