Index: clang-tidy/google/CMakeLists.txt
===================================================================
--- clang-tidy/google/CMakeLists.txt
+++ clang-tidy/google/CMakeLists.txt
@@ -10,6 +10,7 @@
   NamedParameterCheck.cpp
   OverloadedUnaryAndCheck.cpp
   StringReferenceMemberCheck.cpp
+  TodoCommentCheck.cpp
   UnnamedNamespaceInHeaderCheck.cpp
   UsingNamespaceDirectiveCheck.cpp
 
Index: clang-tidy/google/GoogleTidyModule.cpp
===================================================================
--- clang-tidy/google/GoogleTidyModule.cpp
+++ clang-tidy/google/GoogleTidyModule.cpp
@@ -18,6 +18,7 @@
 #include "NamedParameterCheck.h"
 #include "OverloadedUnaryAndCheck.h"
 #include "StringReferenceMemberCheck.h"
+#include "TodoCommentCheck.h"
 #include "UnnamedNamespaceInHeaderCheck.h"
 #include "UsingNamespaceDirectiveCheck.h"
 
@@ -49,6 +50,8 @@
         "google-readability-casting");
     CheckFactories.registerCheck<readability::NamedParameterCheck>(
         "google-readability-function");
+    CheckFactories.registerCheck<readability::TodoCommentCheck>(
+        "google-readability-todo");
   }
 };
 
Index: clang-tidy/google/TodoCommentCheck.h
===================================================================
--- /dev/null
+++ clang-tidy/google/TodoCommentCheck.h
@@ -0,0 +1,33 @@
+//===--- TodoCommentCheck.h - clang-tidy ------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_TODOCOMMENTCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_TODOCOMMENTCHECK_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace readability {
+
+/// \brief Finds TODO comments without a username or bug number.
+///
+/// Corresponding cpplint.py check: readability/todo
+class TodoCommentCheck : public ClangTidyCheck {
+public:
+  TodoCommentCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerPPCallbacks(CompilerInstance &Compiler) override;
+};
+
+} // namespace readability
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_TODOCOMMENTCHECK_H
Index: clang-tidy/google/TodoCommentCheck.cpp
===================================================================
--- /dev/null
+++ clang-tidy/google/TodoCommentCheck.cpp
@@ -0,0 +1,65 @@
+//===--- TodoCommentCheck.cpp - clang-tidy --------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "TodoCommentCheck.h"
+#include "clang/Frontend/CompilerInstance.h"
+#include "clang/Lex/Preprocessor.h"
+
+namespace clang {
+namespace tidy {
+namespace readability {
+
+namespace {
+class TodoCommentHandler : public CommentHandler {
+public:
+  explicit TodoCommentHandler(TodoCommentCheck *Check)
+      : Check(Check), TodoMatch("^// *TODO(\\(.*\\))?:?( )?(.*)$") {}
+
+  bool HandleComment(Preprocessor &PP, SourceRange Range) override {
+    StringRef Text =
+        Lexer::getSourceText(CharSourceRange::getCharRange(Range),
+                             PP.getSourceManager(), PP.getLangOpts());
+
+    SmallVector<StringRef, 4> Matches;
+    if (!TodoMatch.match(Text, &Matches))
+      return false;
+
+    StringRef Username = Matches[1];
+    StringRef Comment = Matches[3];
+
+    if (!Username.empty())
+      return false;
+
+    // If the username is missing put in the current user's name. Not ideal but
+    // works for running tidy locally.
+    // FIXME: Can we get this from a more reliable source?
+    const char *User = std::getenv("USER");
+    if (!User)
+      User = "unknown";
+    std::string NewText = ("// TODO(" + Twine(User) + "): " + Comment).str();
+
+    Check->diag(Range.getBegin(), "missing username/bug in TODO")
+        << FixItHint::CreateReplacement(CharSourceRange::getCharRange(Range),
+                                        NewText);
+    return false;
+  }
+
+private:
+  TodoCommentCheck *Check;
+  llvm::Regex TodoMatch;
+};
+} // namespace
+
+void TodoCommentCheck::registerPPCallbacks(CompilerInstance &Compiler) {
+  Compiler.getPreprocessor().addCommentHandler(new TodoCommentHandler(this));
+}
+
+} // namespace readability
+} // namespace tidy
+} // namespace clang
Index: test/clang-tidy/google-readability-todo.cpp
===================================================================
--- /dev/null
+++ test/clang-tidy/google-readability-todo.cpp
@@ -0,0 +1,25 @@
+// RUN: $(dirname %s)/check_clang_tidy_fix.sh %s google-readability-todo %t
+// REQUIRES: shell
+
+//   TODOfix this
+// CHECK-WARNINGS: [[@LINE-1]]:1: warning: missing username/bug in TODO
+// CHECK-FIXES: // TODO({{[^)]+}}): fix this
+
+//   TODO fix this
+// CHECK-WARNINGS: [[@LINE-1]]:1: warning: missing username/bug in TODO
+// CHECK-FIXES: // TODO({{[^)]+}}): fix this
+
+// TODO fix this
+// CHECK-WARNINGS: [[@LINE-1]]:1: warning: missing username/bug in TODO
+// CHECK-FIXES: // TODO({{[^)]+}}): fix this
+
+// TODO: fix this
+// CHECK-WARNINGS: [[@LINE-1]]:1: warning: missing username/bug in TODO
+// CHECK-FIXES: // TODO({{[^)]+}}): fix this
+
+//   TODO(clang)fix this
+
+// TODO(foo):Fix this
+// TODO(bar):
+// TODO(foo): fix this
+// TODO(b/12345): Fix this