C++11 declares a type safe null pointer

content/common/sandbox_mac_unittest_helper.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_COMMON_SANDBOX_MAC_UNITTEST_HELPER_H_
 #define CONTENT_COMMON_SANDBOX_MAC_UNITTEST_HELPER_H_
 
 #include "base/test/multiprocess_test.h"
 #include "content/common/sandbox_mac.h"
 
@@ skipping 18 matching lines @@
 //      return true; // always succeed.
 //    }
 //  };
 //
 //  // Register the test case you just created.
 //  REGISTER_SANDBOX_TEST_CASE(TestCaseThatRunsInSandboxedSubprocess);
 //
 //  TEST_F(MacSandboxTest, ATest) {
 //    EXPECT_TRUE(RunTestInAllSandboxTypes(
 //                    "TestCaseThatRunsInSandboxedSubprocess",
-//                    NULL));
+//                    nullptr));
 //  }
 
 // Base test type with helper functions to spawn a subprocess that exercises
 // a given test in the sandbox.
 class MacSandboxTest : public base::MultiProcessTest {
  public:
   // Runs a test specified by |test_name| in a sandbox of the type specified
   // by |sandbox_type|. |test_data| is a custom string that a test can pass
-  // to the child process runing in the sandbox, or NULL if additional data is
-  // required.
+  // to the child process runing in the sandbox, or nullptr if additional data
+  // is required.
   // Returns true if the test passes, false if either of the functions in
   // the corresponding MacSandboxTestCase return false.
   bool RunTestInSandbox(content::SandboxType sandbox_type,
                         const char* test_name,
                         const char* test_data);
 
   // Runs the test specified by |test_name| in all the different sandbox types
   // known to content, one by one.
   // Returns true if the test passes, false if either of the functions in
   // the corresponding MacSandboxTestCase return false in any of the spawned
@@ skipping 51 matching lines @@
   namespace { \
     content::internal::RegisterSandboxTest<class_name> \
       register_test##class_name(#class_name); \
   }  // namespace
 
 }  // namespace internal
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_SANDBOX_MAC_UNITTEST_HELPER_H_