[clang-tidy] Add namespaces checkers.

This change contains of two checkers that warn about
1. anonymous namespaces in header files.
2. 'using namespace' directives everywhere.

Differential Revision: http://reviews.llvm.org/D4523

llvm-svn: 213153

1 files changed, 51 insertions, 0 deletions

diff --git a/clang-tools-extra/clang-tidy/google/UnnamedNamespaceInHeaderCheck.cpp b/clang-tools-extra/clang-tidy/google/UnnamedNamespaceInHeaderCheck.cpp
new file mode 100644
index 00000000000..dc2d17093b3
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/google/UnnamedNamespaceInHeaderCheck.cpp
@@ -0,0 +1,51 @@
+//===--- UnnamedNamespaceInHeaderCheck.cpp - clang-tidy ---------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "UnnamedNamespaceInHeaderCheck.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/AST/ASTContext.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace ast_matchers {
+AST_MATCHER(NamespaceDecl, isAnonymousNamespace) {
+  return Node.isAnonymousNamespace();
+}
+} // namespace ast_matchers
+
+namespace tidy {
+namespace build {
+
+void UnnamedNamespaceInHeaderCheck::registerMatchers(
+    ast_matchers::MatchFinder *Finder) {
+  Finder->addMatcher(
+      namespaceDecl(isAnonymousNamespace()).bind("anonymousNamespace"), this);
+}
+
+void
+UnnamedNamespaceInHeaderCheck::check(const MatchFinder::MatchResult &Result) {
+  SourceManager *SM = Result.SourceManager;
+  const auto *N = Result.Nodes.getNodeAs<NamespaceDecl>("anonymousNamespace");
+  SourceLocation Loc = N->getLocStart();
+  if (!Loc.isValid())
+    return;
+
+  // Look if we're inside a header, check for common suffixes only.
+  // TODO: Allow configuring the set of file extensions.
+  StringRef FileName = SM->getPresumedLoc(Loc).getFilename();
+  if (FileName.endswith(".h") || FileName.endswith(".hh") ||
+      FileName.endswith(".hpp") || FileName.endswith(".hxx"))
+    diag(Loc, "do not use unnamed namespaces in header files.");
+}
+
+} // namespace build
+} // namespace tidy
+} // namespace clang