Index: clang-tidy/google/GoogleTidyModule.cpp
===================================================================
--- clang-tidy/google/GoogleTidyModule.cpp
+++ clang-tidy/google/GoogleTidyModule.cpp
@@ -21,6 +21,7 @@
 #include "TodoCommentCheck.h"
 #include "UnnamedNamespaceInHeaderCheck.h"
 #include "UsingNamespaceDirectiveCheck.h"
+#include "../llvm/NamespaceCommentCheck.h"
 
 using namespace clang::ast_matchers;
 
@@ -52,6 +53,8 @@
         "google-readability-function");
     CheckFactories.registerCheck<readability::TodoCommentCheck>(
         "google-readability-todo");
+    CheckFactories.registerCheck<NamespaceCommentCheck>(
+        "google-readability-namespace-comments");
   }
 };
 
Index: clang-tidy/llvm/NamespaceCommentCheck.cpp
===================================================================
--- clang-tidy/llvm/NamespaceCommentCheck.cpp
+++ clang-tidy/llvm/NamespaceCommentCheck.cpp
@@ -25,7 +25,8 @@
                               "namespace( +([a-zA-Z0-9_]+))? *(\\*/)?$",
                               llvm::Regex::IgnoreCase),
       ShortNamespaceLines(Options.get("ShortNamespaceLines", 1u)),
-      SpacesBeforeComments(Options.get("SpacesBeforeComments", 1u)) {}
+      SpacesBeforeComments(Options.get("SpacesBeforeComments",
+                                       Name.startswith("google") ? 2u : 1u)) {}
 
 void NamespaceCommentCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
   Options.store(Opts, "ShortNamespaceLines", ShortNamespaceLines);
@@ -42,12 +43,10 @@
          Sources.getFileID(Loc1) == Sources.getFileID(Loc2);
 }
 
-std::string getNamespaceComment(const NamespaceDecl *ND, bool InsertLineBreak,
-                                unsigned SpacesBeforeComments) {
+std::string getNamespaceComment(const NamespaceDecl *ND, bool InsertLineBreak) {
   std::string Fix = "// namespace";
   if (!ND->isAnonymousNamespace())
-    Fix.append(std::string(SpacesBeforeComments, ' '))
-        .append(ND->getNameAsString());
+    Fix.append(" ").append(ND->getNameAsString());
   if (InsertLineBreak)
     Fix.append("\n");
   return Fix;
@@ -105,8 +104,7 @@
       diag(Loc, "namespace closing comment refers to a wrong namespace '%0'")
           << NamespaceNameInComment
           << FixItHint::CreateReplacement(
-                 OldCommentRange,
-                 getNamespaceComment(ND, NeedLineBreak, SpacesBeforeComments));
+                 OldCommentRange, getNamespaceComment(ND, NeedLineBreak));
       return;
     }
 
@@ -118,9 +116,9 @@
   }
 
   diag(ND->getLocation(), "namespace not terminated with a closing comment")
-      << FixItHint::CreateInsertion(
-          AfterRBrace,
-          " " + getNamespaceComment(ND, NeedLineBreak, SpacesBeforeComments));
+      << FixItHint::CreateInsertion(AfterRBrace,
+                                    std::string(SpacesBeforeComments, ' ') +
+                                        getNamespaceComment(ND, NeedLineBreak));
 }
 
 } // namespace tidy
Index: test/clang-tidy/google-readability-namespace-comments.cpp
===================================================================
--- /dev/null
+++ test/clang-tidy/google-readability-namespace-comments.cpp
@@ -0,0 +1,15 @@
+// RUN: $(dirname %s)/check_clang_tidy_fix.sh %s google-readability-namespace-comments %t
+// REQUIRES: shell
+
+// CHECK-MESSAGES: :[[@LINE+2]]:11: warning: namespace not terminated with a closing comment [google-readability-namespace-comments]
+// CHECK-MESSAGES: :[[@LINE+2]]:11: warning: namespace not terminated with a closing comment [google-readability-namespace-comments]
+namespace n1 {
+namespace n2 {
+
+}
+}
+// CHECK-FIXES: }  // namespace n2
+// CHECK-FIXES: }  // namespace n1
+
+
+namespace short1 { namespace short2 { } }