Apply clang-tidy modernize-use-nullptr to googletest.

Now that googletest has moved to C++11, it should no longer
use NULL or 0 for the null pointer. This patch converts all
such usages to nullptr using clang-tidy.

This prevents LLVM from issuing -Wzero-as-null-pointer-constant
warnings.

PiperOrigin-RevId: 215814400

8 files changed, 129 insertions, 141 deletions

diff --git a/googletest/src/gtest-death-test.cc b/googletest/src/gtest-death-test.cc
index 0908355..b3a572a 100644
--- a/googletest/src/gtest-death-test.cc
+++ b/googletest/src/gtest-death-test.cc
@@ -281,7 +281,7 @@ static void DeathTestAbort(const std::string& message) {
   // the heap for any additional non-minuscule memory requirements.
   const InternalRunDeathTestFlag* const flag =
       GetUnitTestImpl()->internal_run_death_test_flag();
-  if (flag != NULL) {
+  if (flag != nullptr) {
     FILE* parent = posix::FDOpen(flag->write_fd(), "w");
     fputc(kDeathTestInternalError, parent);
     fprintf(parent, "%s", message.c_str());
@@ -361,7 +361,7 @@ static void FailFromInternalError(int fd) {
 // for the current test.
 DeathTest::DeathTest() {
   TestInfo* const info = GetUnitTestImpl()->current_test_info();
-  if (info == NULL) {
+  if (info == nullptr) {
     DeathTestAbort("Cannot run a death test outside of a TEST or "
                    "TEST_F construct");
   }
@@ -1115,9 +1115,7 @@ class ExecDeathTest : public ForkingDeathTest {
 // Utility class for accumulating command-line arguments.
 class Arguments {
  public:
-  Arguments() {
-    args_.push_back(NULL);
-  }
+  Arguments() { args_.push_back(nullptr); }
 
   ~Arguments() {
     for (std::vector<char*>::iterator i = args_.begin(); i != args_.end();
@@ -1288,7 +1286,7 @@ static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) {
     static const bool stack_grows_down = StackGrowsDown();
     const size_t stack_size = getpagesize();
     // MMAP_ANONYMOUS is not defined on Mac, so we use MAP_ANON instead.
-    void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE,
+    void* const stack = mmap(nullptr, stack_size, PROT_READ | PROT_WRITE,
                              MAP_ANON | MAP_PRIVATE, -1, 0);
     GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED);
 
@@ -1320,7 +1318,7 @@ static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) {
 #  endif  // GTEST_OS_QNX
 #  if GTEST_OS_LINUX
   GTEST_DEATH_TEST_CHECK_SYSCALL_(
-      sigaction(SIGPROF, &saved_sigprof_action, NULL));
+      sigaction(SIGPROF, &saved_sigprof_action, nullptr));
 #  endif  // GTEST_OS_LINUX
 
   GTEST_DEATH_TEST_CHECK_(child_pid != -1);
@@ -1338,7 +1336,7 @@ DeathTest::TestRole ExecDeathTest::AssumeRole() {
   const TestInfo* const info = impl->current_test_info();
   const int death_test_index = info->result()->death_test_count();
 
-  if (flag != NULL) {
+  if (flag != nullptr) {
     set_write_fd(flag->write_fd());
     return EXECUTE_TEST;
   }
@@ -1393,7 +1391,7 @@ bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex,
   const int death_test_index = impl->current_test_info()
       ->increment_death_test_count();
 
-  if (flag != NULL) {
+  if (flag != nullptr) {
     if (death_test_index > flag->index()) {
       DeathTest::set_last_death_test_message(
           "Death test count (" + StreamableToString(death_test_index)
@@ -1404,7 +1402,7 @@ bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex,
 
     if (!(flag->file() == file && flag->line() == line &&
           flag->index() == death_test_index)) {
-      *test = NULL;
+      *test = nullptr;
       return true;
     }
   }
@@ -1515,7 +1513,7 @@ static int GetStatusFileDescriptor(unsigned int parent_process_id,
 // initialized from the GTEST_FLAG(internal_run_death_test) flag if
 // the flag is specified; otherwise returns NULL.
 InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {
-  if (GTEST_FLAG(internal_run_death_test) == "") return NULL;
+  if (GTEST_FLAG(internal_run_death_test) == "") return nullptr;
 
   // GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we
   // can use it here.
diff --git a/googletest/src/gtest-filepath.cc b/googletest/src/gtest-filepath.cc
index a7e65c0..317d17c 100644
--- a/googletest/src/gtest-filepath.cc
+++ b/googletest/src/gtest-filepath.cc
@@ -111,7 +111,7 @@ FilePath FilePath::GetCurrentDir() {
   // however, so fallback only when failure is detected.
   return FilePath(result == NULL ? kCurrentDirectoryString : cwd);
 # endif  // GTEST_OS_NACL
-  return FilePath(result == NULL ? "" : cwd);
+  return FilePath(result == nullptr ? "" : cwd);
 #endif  // GTEST_OS_WINDOWS_MOBILE
 }
 
@@ -352,7 +352,7 @@ FilePath FilePath::RemoveTrailingPathSeparator() const {
 // redundancies that might be in a pathname involving "." or "..".
 // FIXME: handle Windows network shares (e.g. \\server\share).
 void FilePath::Normalize() {
-  if (pathname_.c_str() == NULL) {
+  if (pathname_.c_str() == nullptr) {
     pathname_ = "";
     return;
   }
diff --git a/googletest/src/gtest-internal-inl.h b/googletest/src/gtest-internal-inl.h
index f79b1ad..f05de04 100644
--- a/googletest/src/gtest-internal-inl.h
+++ b/googletest/src/gtest-internal-inl.h
@@ -585,14 +585,14 @@ class GTEST_API_ UnitTestImpl {
   // total_test_case_count() - 1. If i is not in that range, returns NULL.
   const TestCase* GetTestCase(int i) const {
     const int index = GetElementOr(test_case_indices_, i, -1);
-    return index < 0 ? NULL : test_cases_[i];
+    return index < 0 ? nullptr : test_cases_[i];
   }
 
   // Gets the i-th test case among all the test cases. i can range from 0 to
   // total_test_case_count() - 1. If i is not in that range, returns NULL.
   TestCase* GetMutableTestCase(int i) {
     const int index = GetElementOr(test_case_indices_, i, -1);
-    return index < 0 ? NULL : test_cases_[index];
+    return index < 0 ? nullptr : test_cases_[index];
   }
 
   // Provides access to the event listener list.
@@ -1158,8 +1158,7 @@ class StreamingListener : public EmptyTestEventListener {
 
   void OnTestPartResult(const TestPartResult& test_part_result) {
     const char* file_name = test_part_result.file_name();
-    if (file_name == NULL)
-      file_name = "";
+    if (file_name == nullptr) file_name = "";
     SendLn("event=TestPartResult&file=" + UrlEncode(file_name) +
            "&line=" + StreamableToString(test_part_result.line_number()) +
            "&message=" + UrlEncode(test_part_result.message()));
diff --git a/googletest/src/gtest-port.cc b/googletest/src/gtest-port.cc
index fecb5d1..91f285c 100644
--- a/googletest/src/gtest-port.cc
+++ b/googletest/src/gtest-port.cc
@@ -935,7 +935,7 @@ const char kUnknownFile[] = "unknown file";
 // Formats a source file path and a line number as they would appear
 // in an error message from the compiler used to compile this code.
 GTEST_API_ ::std::string FormatFileLocation(const char* file, int line) {
-  const std::string file_name(file == NULL ? kUnknownFile : file);
+  const std::string file_name(file == nullptr ? kUnknownFile : file);
 
   if (line < 0) {
     return file_name + ":";
@@ -954,7 +954,7 @@ GTEST_API_ ::std::string FormatFileLocation(const char* file, int line) {
 // to the file location it produces, unlike FormatFileLocation().
 GTEST_API_ ::std::string FormatCompilerIndependentFileLocation(
     const char* file, int line) {
-  const std::string file_name(file == NULL ? kUnknownFile : file);
+  const std::string file_name(file == nullptr ? kUnknownFile : file);
 
   if (line < 0)
     return file_name;
@@ -1034,7 +1034,7 @@ class CapturedStream {
     const int captured_fd = mkstemp(name_template);
     filename_ = name_template;
 # endif  // GTEST_OS_WINDOWS
-    fflush(NULL);
+    fflush(nullptr);
     dup2(captured_fd, fd_);
     close(captured_fd);
   }
@@ -1046,7 +1046,7 @@ class CapturedStream {
   std::string GetCapturedString() {
     if (uncaptured_fd_ != -1) {
       // Restores the original stream.
-      fflush(NULL);
+      fflush(nullptr);
       dup2(uncaptured_fd_, fd_);
       close(uncaptured_fd_);
       uncaptured_fd_ = -1;
@@ -1069,13 +1069,13 @@ class CapturedStream {
 
 GTEST_DISABLE_MSC_DEPRECATED_POP_()
 
-static CapturedStream* g_captured_stderr = NULL;
-static CapturedStream* g_captured_stdout = NULL;
+static CapturedStream* g_captured_stderr = nullptr;
+static CapturedStream* g_captured_stdout = nullptr;
 
 // Starts capturing an output stream (stdout/stderr).
 static void CaptureStream(int fd, const char* stream_name,
                           CapturedStream** stream) {
-  if (*stream != NULL) {
+  if (*stream != nullptr) {
     GTEST_LOG_(FATAL) << "Only one " << stream_name
                       << " capturer can exist at a time.";
   }
@@ -1087,7 +1087,7 @@ static std::string GetCapturedStream(CapturedStream** captured_stream) {
   const std::string content = (*captured_stream)->GetCapturedString();
 
   delete *captured_stream;
-  *captured_stream = NULL;
+  *captured_stream = nullptr;
 
   return content;
 }
@@ -1146,10 +1146,11 @@ std::string ReadEntireFile(FILE* file) {
 }
 
 #if GTEST_HAS_DEATH_TEST
-static const std::vector<std::string>* g_injected_test_argvs = NULL;  // Owned.
+static const std::vector<std::string>* g_injected_test_argvs =
+    nullptr;  // Owned.
 
 std::vector<std::string> GetInjectableArgvs() {
-  if (g_injected_test_argvs != NULL) {
+  if (g_injected_test_argvs != nullptr) {
     return *g_injected_test_argvs;
   }
   return GetArgvs();
@@ -1174,7 +1175,7 @@ void SetInjectableArgvs(const std::vector< ::string>& new_argvs) {
 
 void ClearInjectableArgvs() {
   delete g_injected_test_argvs;
-  g_injected_test_argvs = NULL;
+  g_injected_test_argvs = nullptr;
 }
 #endif  // GTEST_HAS_DEATH_TEST
 
@@ -1207,7 +1208,7 @@ static std::string FlagToEnvVar(const char* flag) {
 // unchanged and returns false.
 bool ParseInt32(const Message& src_text, const char* str, Int32* value) {
   // Parses the environment variable as a decimal integer.
-  char* end = NULL;
+  char* end = nullptr;
   const long long_value = strtol(str, &end, 10);  // NOLINT
 
   // Has strtol() consumed all characters in the string?
@@ -1296,7 +1297,7 @@ Int32 Int32FromGTestEnv(const char* flag, Int32 default_value) {
 std::string OutputFlagAlsoCheckEnvVar(){
   std::string default_value_for_output_flag = "";
   const char* xml_output_file_env = posix::GetEnv("XML_OUTPUT_FILE");
-  if (NULL != xml_output_file_env) {
+  if (nullptr != xml_output_file_env) {
     default_value_for_output_flag = std::string("xml:") + xml_output_file_env;
   }
   return default_value_for_output_flag;
diff --git a/googletest/src/gtest-printers.cc b/googletest/src/gtest-printers.cc
index de4d245..3c0e758 100644
--- a/googletest/src/gtest-printers.cc
+++ b/googletest/src/gtest-printers.cc
@@ -327,7 +327,7 @@ void UniversalPrintArray(const wchar_t* begin, size_t len, ostream* os) {
 
 // Prints the given C string to the ostream.
 void PrintTo(const char* s, ostream* os) {
-  if (s == NULL) {
+  if (s == nullptr) {
     *os << "NULL";
   } else {
     *os << ImplicitCast_<const void*>(s) << " pointing to ";
@@ -344,7 +344,7 @@ void PrintTo(const char* s, ostream* os) {
 #if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
 // Prints the given wide C string to the ostream.
 void PrintTo(const wchar_t* s, ostream* os) {
-  if (s == NULL) {
+  if (s == nullptr) {
     *os << "NULL";
   } else {
     *os << ImplicitCast_<const void*>(s) << " pointing to ";
diff --git a/googletest/src/gtest-test-part.cc b/googletest/src/gtest-test-part.cc
index 2855e3e..515b308 100644
--- a/googletest/src/gtest-test-part.cc
+++ b/googletest/src/gtest-test-part.cc
@@ -41,8 +41,7 @@ using internal::GetUnitTestImpl;
 // in it.
 std::string TestPartResult::ExtractSummary(const char* message) {
   const char* const stack_trace = strstr(message, internal::kStackTraceMarker);
-  return stack_trace == NULL ? message :
-      std::string(message, stack_trace);
+  return stack_trace == nullptr ? message : std::string(message, stack_trace);
 }
 
 // Prints a TestPartResult object.
diff --git a/googletest/src/gtest-typed-test.cc b/googletest/src/gtest-typed-test.cc
index 1dc2ad3..a305ed1 100644
--- a/googletest/src/gtest-typed-test.cc
+++ b/googletest/src/gtest-typed-test.cc
@@ -48,7 +48,7 @@ static const char* SkipSpaces(const char* str) {
 static std::vector<std::string> SplitIntoTestNames(const char* src) {
   std::vector<std::string> name_vec;
   src = SkipSpaces(src);
-  for (; src != NULL; src = SkipComma(src)) {
+  for (; src != nullptr; src = SkipComma(src)) {
     name_vec.push_back(StripTrailingSpaces(GetPrefixUntilComma(src)));
   }
   return name_vec;
diff --git a/googletest/src/gtest.cc b/googletest/src/gtest.cc
index 996be23..737fdc2 100644
--- a/googletest/src/gtest.cc
+++ b/googletest/src/gtest.cc
@@ -196,14 +196,14 @@ bool g_help_flag = false;
 
 // Utilty function to Open File for Writing
 static FILE* OpenFileForWriting(const std::string& output_file) {
-  FILE* fileout = NULL;
+  FILE* fileout = nullptr;
   FilePath output_file_path(output_file);
   FilePath output_dir(output_file_path.RemoveFileName());
 
   if (output_dir.CreateDirectoriesRecursively()) {
     fileout = posix::FOpen(output_file.c_str(), "w");
   }
-  if (fileout == NULL) {
+  if (fileout == nullptr) {
     GTEST_LOG_(FATAL) << "Unable to open file \"" << output_file << "\"";
   }
   return fileout;
@@ -216,7 +216,7 @@ static FILE* OpenFileForWriting(const std::string& output_file) {
 static const char* GetDefaultFilter() {
   const char* const testbridge_test_only =
       internal::posix::GetEnv("TESTBRIDGE_TEST_ONLY");
-  if (testbridge_test_only != NULL) {
+  if (testbridge_test_only != nullptr) {
     return testbridge_test_only;
   }
   return kUniversalFilter;
@@ -460,9 +460,9 @@ FilePath GetCurrentExecutableName() {
 std::string UnitTestOptions::GetOutputFormat() {
   const char* const gtest_output_flag = GTEST_FLAG(output).c_str();
   const char* const colon = strchr(gtest_output_flag, ':');
-  return (colon == NULL) ?
-      std::string(gtest_output_flag) :
-      std::string(gtest_output_flag, colon - gtest_output_flag);
+  return (colon == nullptr)
+             ? std::string(gtest_output_flag)
+             : std::string(gtest_output_flag, colon - gtest_output_flag);
 }
 
 // Returns the name of the requested output file, or the default if none
@@ -475,7 +475,7 @@ std::string UnitTestOptions::GetAbsolutePathToOutputFile() {
     format = std::string(kDefaultOutputFormat);
 
   const char* const colon = strchr(gtest_output_flag, ':');
-  if (colon == NULL)
+  if (colon == nullptr)
     return internal::FilePath::MakeFileName(
         internal::FilePath(
             UnitTest::GetInstance()->original_working_dir()),
@@ -535,7 +535,7 @@ bool UnitTestOptions::MatchesFilter(
     cur_pattern = strchr(cur_pattern, ':');
 
     // Returns if no more pattern can be found.
-    if (cur_pattern == NULL) {
+    if (cur_pattern == nullptr) {
       return false;
     }
 
@@ -556,7 +556,7 @@ bool UnitTestOptions::FilterMatchesTest(const std::string &test_case_name,
   const char* const dash = strchr(p, '-');
   std::string positive;
   std::string negative;
-  if (dash == NULL) {
+  if (dash == nullptr) {
     positive = GTEST_FLAG(filter).c_str();  // Whole string is a positive filter
     negative = "";
   } else {
@@ -701,7 +701,7 @@ static AssertionResult HasOneFailure(const char* /* results_expr */,
                               << r;
   }
 
-  if (strstr(r.message(), substr.c_str()) == NULL) {
+  if (strstr(r.message(), substr.c_str()) == nullptr) {
     return AssertionFailure() << "Expected: " << expected << " containing \""
                               << substr << "\"\n"
                               << "  Actual:\n"
@@ -888,7 +888,7 @@ TimeInMillis GetTimeInMillis() {
   return static_cast<TimeInMillis>(now.time) * 1000 + now.millitm;
 #elif GTEST_HAS_GETTIMEOFDAY_
   struct timeval now;
-  gettimeofday(&now, NULL);
+  gettimeofday(&now, nullptr);
   return static_cast<TimeInMillis>(now.tv_sec) * 1000 + now.tv_usec / 1000;
 #else
 # error "Don't know how to get the current time on your system."
@@ -941,9 +941,9 @@ const char* String::Utf16ToAnsi(LPCWSTR utf16_str)  {
 // C string is considered different to any non-NULL C string,
 // including the empty string.
 bool String::CStringEquals(const char * lhs, const char * rhs) {
-  if ( lhs == NULL ) return rhs == NULL;
+  if (lhs == nullptr) return rhs == nullptr;
 
-  if ( rhs == NULL ) return false;
+  if (rhs == nullptr) return false;
 
   return strcmp(lhs, rhs) == 0;
 }
@@ -1035,10 +1035,9 @@ std::string Message::GetString() const {
 // Used in EXPECT_TRUE/FALSE(assertion_result).
 AssertionResult::AssertionResult(const AssertionResult& other)
     : success_(other.success_),
-      message_(other.message_.get() != NULL ?
-               new ::std::string(*other.message_) :
-               static_cast< ::std::string*>(NULL)) {
-}
+      message_(other.message_.get() != nullptr
+                   ? new ::std::string(*other.message_)
+                   : static_cast< ::std::string*>(nullptr)) {}
 
 // Swaps two AssertionResults.
 void AssertionResult::swap(AssertionResult& other) {
@@ -1050,8 +1049,7 @@ void AssertionResult::swap(AssertionResult& other) {
 // Returns the assertion's negation. Used with EXPECT/ASSERT_FALSE.
 AssertionResult AssertionResult::operator!() const {
   AssertionResult negation(!success_);
-  if (message_.get() != NULL)
-    negation << *message_;
+  if (message_.get() != nullptr) negation << *message_;
   return negation;
 }
 
@@ -1605,17 +1603,15 @@ namespace {
 // only.
 
 bool IsSubstringPred(const char* needle, const char* haystack) {
-  if (needle == NULL || haystack == NULL)
-    return needle == haystack;
+  if (needle == nullptr || haystack == nullptr) return needle == haystack;
 
-  return strstr(haystack, needle) != NULL;
+  return strstr(haystack, needle) != nullptr;
 }
 
 bool IsSubstringPred(const wchar_t* needle, const wchar_t* haystack) {
-  if (needle == NULL || haystack == NULL)
-    return needle == haystack;
+  if (needle == nullptr || haystack == nullptr) return needle == haystack;
 
-  return wcsstr(haystack, needle) != NULL;
+  return wcsstr(haystack, needle) != nullptr;
 }
 
 // StringType here can be either ::std::string or ::std::wstring.
@@ -1896,7 +1892,7 @@ std::string WideStringToUtf8(const wchar_t* str, int num_chars) {
 // Converts a wide C string to an std::string using the UTF-8 encoding.
 // NULL will be converted to "(null)".
 std::string String::ShowWideCString(const wchar_t * wide_c_str) {
-  if (wide_c_str == NULL)  return "(null)";
+  if (wide_c_str == nullptr) return "(null)";
 
   return internal::WideStringToUtf8(wide_c_str, -1);
 }
@@ -1908,9 +1904,9 @@ std::string String::ShowWideCString(const wchar_t * wide_c_str) {
 // C string is considered different to any non-NULL C string,
 // including the empty string.
 bool String::WideCStringEquals(const wchar_t * lhs, const wchar_t * rhs) {
-  if (lhs == NULL) return rhs == NULL;
+  if (lhs == nullptr) return rhs == nullptr;
 
-  if (rhs == NULL) return false;
+  if (rhs == nullptr) return false;
 
   return wcscmp(lhs, rhs) == 0;
 }
@@ -1953,10 +1949,8 @@ AssertionResult CmpHelperSTRNE(const char* s1_expression,
 // NULL C string is considered different to any non-NULL C string,
 // including the empty string.
 bool String::CaseInsensitiveCStringEquals(const char * lhs, const char * rhs) {
-  if (lhs == NULL)
-    return rhs == NULL;
-  if (rhs == NULL)
-    return false;
+  if (lhs == nullptr) return rhs == nullptr;
+  if (rhs == nullptr) return false;
   return posix::StrCaseCmp(lhs, rhs) == 0;
 }
 
@@ -1974,9 +1968,9 @@ bool String::CaseInsensitiveCStringEquals(const char * lhs, const char * rhs) {
   // current locale.
 bool String::CaseInsensitiveWideCStringEquals(const wchar_t* lhs,
                                               const wchar_t* rhs) {
-  if (lhs == NULL) return rhs == NULL;
+  if (lhs == nullptr) return rhs == nullptr;
 
-  if (rhs == NULL) return false;
+  if (rhs == nullptr) return false;
 
 #if GTEST_OS_WINDOWS
   return _wcsicmp(lhs, rhs) == 0;
@@ -2309,10 +2303,10 @@ void ReportFailureInUnknownLocation(TestPartResult::Type result_type,
   // AddTestPartResult.
   UnitTest::GetInstance()->AddTestPartResult(
       result_type,
-      NULL,  // No info about the source file where the exception occurred.
-      -1,    // We have no info on which line caused the exception.
+      nullptr,  // No info about the source file where the exception occurred.
+      -1,       // We have no info on which line caused the exception.
       message,
-      "");   // No stack trace, either.
+      "");  // No stack trace, either.
 }
 
 }  // namespace internal
@@ -2562,16 +2556,15 @@ bool Test::IsSkipped() {
 // Constructs a TestInfo object. It assumes ownership of the test factory
 // object.
 TestInfo::TestInfo(const std::string& a_test_case_name,
-                   const std::string& a_name,
-                   const char* a_type_param,
+                   const std::string& a_name, const char* a_type_param,
                    const char* a_value_param,
                    internal::CodeLocation a_code_location,
                    internal::TypeId fixture_class_id,
                    internal::TestFactoryBase* factory)
     : test_case_name_(a_test_case_name),
       name_(a_name),
-      type_param_(a_type_param ? new std::string(a_type_param) : NULL),
-      value_param_(a_value_param ? new std::string(a_value_param) : NULL),
+      type_param_(a_type_param ? new std::string(a_type_param) : nullptr),
+      value_param_(a_value_param ? new std::string(a_value_param) : nullptr),
       location_(a_code_location),
       fixture_class_id_(fixture_class_id),
       should_run_(false),
@@ -2725,7 +2718,7 @@ void TestInfo::Run() {
 
   // Tells UnitTest to stop associating assertion results to this
   // test.
-  impl->set_current_test_info(NULL);
+  impl->set_current_test_info(nullptr);
 }
 
 // class TestCase
@@ -2783,12 +2776,11 @@ TestCase::TestCase(const char* a_name, const char* a_type_param,
                    Test::SetUpTestCaseFunc set_up_tc,
                    Test::TearDownTestCaseFunc tear_down_tc)
     : name_(a_name),
-      type_param_(a_type_param ? new std::string(a_type_param) : NULL),
+      type_param_(a_type_param ? new std::string(a_type_param) : nullptr),
       set_up_tc_(set_up_tc),
       tear_down_tc_(tear_down_tc),
       should_run_(false),
-      elapsed_time_(0) {
-}
+      elapsed_time_(0) {}
 
 // Destructor of TestCase.
 TestCase::~TestCase() {
@@ -2800,14 +2792,14 @@ TestCase::~TestCase() {
 // total_test_count() - 1. If i is not in that range, returns NULL.
 const TestInfo* TestCase::GetTestInfo(int i) const {
   const int index = GetElementOr(test_indices_, i, -1);
-  return index < 0 ? NULL : test_info_list_[index];
+  return index < 0 ? nullptr : test_info_list_[index];
 }
 
 // Returns the i-th test among all the tests. i can range from 0 to
 // total_test_count() - 1. If i is not in that range, returns NULL.
 TestInfo* TestCase::GetMutableTestInfo(int i) {
   const int index = GetElementOr(test_indices_, i, -1);
-  return index < 0 ? NULL : test_info_list_[index];
+  return index < 0 ? nullptr : test_info_list_[index];
 }
 
 // Adds a test to this test case.  Will delete the test upon
@@ -2842,7 +2834,7 @@ void TestCase::Run() {
       this, &TestCase::RunTearDownTestCase, "TearDownTestCase()");
 
   repeater->OnTestCaseEnd(*this);
-  impl->set_current_test_case(NULL);
+  impl->set_current_test_case(nullptr);
 }
 
 // Clears the results of all tests in this test case.
@@ -3001,7 +2993,8 @@ static const char* GetAnsiColorCode(GTestColor color) {
     case COLOR_RED:     return "1";
     case COLOR_GREEN:   return "2";
     case COLOR_YELLOW:  return "3";
-    default:            return NULL;
+    default:
+      return nullptr;
   };
 }
 
@@ -3106,14 +3099,13 @@ static void PrintFullTestCommentIfPresent(const TestInfo& test_info) {
   const char* const type_param = test_info.type_param();
   const char* const value_param = test_info.value_param();
 
-  if (type_param != NULL || value_param != NULL) {
+  if (type_param != nullptr || value_param != nullptr) {
     printf(", where ");
-    if (type_param != NULL) {
+    if (type_param != nullptr) {
       printf("%s = %s", kTypeParamLabel, type_param);
-      if (value_param != NULL)
-        printf(" and ");
+      if (value_param != nullptr) printf(" and ");
     }
-    if (value_param != NULL) {
+    if (value_param != nullptr) {
       printf("%s = %s", kValueParamLabel, value_param);
     }
   }
@@ -3197,7 +3189,7 @@ void PrettyUnitTestResultPrinter::OnTestCaseStart(const TestCase& test_case) {
       FormatCountableNoun(test_case.test_to_run_count(), "test", "tests");
   ColoredPrintf(COLOR_GREEN, "[----------] ");
   printf("%s from %s", counts.c_str(), test_case.name());
-  if (test_case.type_param() == NULL) {
+  if (test_case.type_param() == nullptr) {
     printf("\n");
   } else {
     printf(", where %s = %s\n", kTypeParamLabel, test_case.type_param());
@@ -3421,7 +3413,7 @@ TestEventListener* TestEventRepeater::Release(TestEventListener *listener) {
     }
   }
 
-  return NULL;
+  return nullptr;
 }
 
 // Since most methods are very similar, use macros to reduce boilerplate.
@@ -3695,7 +3687,7 @@ static bool PortableLocaltime(time_t seconds, struct tm* out) {
   *out = *tm_ptr;
   return true;
 #else
-  return localtime_r(&seconds, out) != NULL;
+  return localtime_r(&seconds, out) != nullptr;
 #endif
 }
 
@@ -3721,7 +3713,7 @@ void XmlUnitTestResultPrinter::OutputXmlCDataSection(::std::ostream* stream,
   *stream << "<![CDATA[";
   for (;;) {
     const char* const next_segment = strstr(segment, "]]>");
-    if (next_segment != NULL) {
+    if (next_segment != nullptr) {
       stream->write(
           segment, static_cast<std::streamsize>(next_segment - segment));
       *stream << "]]>]]&gt;<![CDATA[";
@@ -3765,11 +3757,11 @@ void XmlUnitTestResultPrinter::OutputXmlTestInfo(::std::ostream* stream,
   *stream << "    <testcase";
   OutputXmlAttribute(stream, kTestcase, "name", test_info.name());
 
-  if (test_info.value_param() != NULL) {
+  if (test_info.value_param() != nullptr) {
     OutputXmlAttribute(stream, kTestcase, "value_param",
                        test_info.value_param());
   }
-  if (test_info.type_param() != NULL) {
+  if (test_info.type_param() != nullptr) {
     OutputXmlAttribute(stream, kTestcase, "type_param", test_info.type_param());
   }
   if (GTEST_FLAG(list_tests)) {
@@ -4130,11 +4122,11 @@ void JsonUnitTestResultPrinter::OutputJsonTestInfo(::std::ostream* stream,
   *stream << Indent(8) << "{\n";
   OutputJsonKey(stream, kTestcase, "name", test_info.name(), kIndent);
 
-  if (test_info.value_param() != NULL) {
+  if (test_info.value_param() != nullptr) {
     OutputJsonKey(stream, kTestcase, "value_param",
                   test_info.value_param(), kIndent);
   }
-  if (test_info.type_param() != NULL) {
+  if (test_info.type_param() != nullptr) {
     OutputJsonKey(stream, kTestcase, "type_param", test_info.type_param(),
                   kIndent);
   }
@@ -4335,7 +4327,7 @@ void StreamingListener::SocketWriter::MakeConnection() {
   memset(&hints, 0, sizeof(hints));
   hints.ai_family = AF_UNSPEC;    // To allow both IPv4 and IPv6 addresses.
   hints.ai_socktype = SOCK_STREAM;
-  addrinfo* servinfo = NULL;
+  addrinfo* servinfo = nullptr;
 
   // Use the getaddrinfo() to get a linked list of IP addresses for
   // the given host name.
@@ -4347,7 +4339,7 @@ void StreamingListener::SocketWriter::MakeConnection() {
   }
 
   // Loop through all the results and connect to the first we can.
-  for (addrinfo* cur_addr = servinfo; sockfd_ == -1 && cur_addr != NULL;
+  for (addrinfo* cur_addr = servinfo; sockfd_ == -1 && cur_addr != nullptr;
        cur_addr = cur_addr->ai_next) {
     sockfd_ = socket(
         cur_addr->ai_family, cur_addr->ai_socktype, cur_addr->ai_protocol);
@@ -4479,9 +4471,8 @@ class ScopedPrematureExitFile {
 
 TestEventListeners::TestEventListeners()
     : repeater_(new internal::TestEventRepeater()),
-      default_result_printer_(NULL),
-      default_xml_generator_(NULL) {
-}
+      default_result_printer_(nullptr),
+      default_xml_generator_(nullptr) {}
 
 TestEventListeners::~TestEventListeners() { delete repeater_; }
 
@@ -4498,9 +4489,9 @@ void TestEventListeners::Append(TestEventListener* listener) {
 // NULL if the listener is not found in the list.
 TestEventListener* TestEventListeners::Release(TestEventListener* listener) {
   if (listener == default_result_printer_)
-    default_result_printer_ = NULL;
+    default_result_printer_ = nullptr;
   else if (listener == default_xml_generator_)
-    default_xml_generator_ = NULL;
+    default_xml_generator_ = nullptr;
   return repeater_->Release(listener);
 }
 
@@ -4519,8 +4510,7 @@ void TestEventListeners::SetDefaultResultPrinter(TestEventListener* listener) {
     // list.
     delete Release(default_result_printer_);
     default_result_printer_ = listener;
-    if (listener != NULL)
-      Append(listener);
+    if (listener != nullptr) Append(listener);
   }
 }
 
@@ -4535,8 +4525,7 @@ void TestEventListeners::SetDefaultXmlGenerator(TestEventListener* listener) {
     // list.
     delete Release(default_xml_generator_);
     default_xml_generator_ = listener;
-    if (listener != NULL)
-      Append(listener);
+    if (listener != nullptr) Append(listener);
   }
 }
 
@@ -4688,8 +4677,8 @@ TestEventListeners& UnitTest::listeners() {
 // We don't protect this under mutex_, as we only support calling it
 // from the main thread.
 Environment* UnitTest::AddEnvironment(Environment* env) {
-  if (env == NULL) {
-    return NULL;
+  if (env == nullptr) {
+    return nullptr;
   }
 
   impl_->environments().push_back(env);
@@ -4721,7 +4710,7 @@ void UnitTest::AddTestPartResult(
     }
   }
 
-  if (os_stack_trace.c_str() != NULL && !os_stack_trace.empty()) {
+  if (os_stack_trace.c_str() != nullptr && !os_stack_trace.empty()) {
     msg << internal::kStackTraceMarker << os_stack_trace;
   }
 
@@ -4809,8 +4798,9 @@ int UnitTest::Run() {
   // that understands the premature-exit-file protocol to report the
   // test as having failed.
   const internal::ScopedPrematureExitFile premature_exit_file(
-      in_death_test_child_process ?
-      NULL : internal::posix::GetEnv("TEST_PREMATURE_EXIT_FILE"));
+      in_death_test_child_process
+          ? nullptr
+          : internal::posix::GetEnv("TEST_PREMATURE_EXIT_FILE"));
 
   // Captures the value of GTEST_FLAG(catch_exceptions).  This value will be
   // used for the duration of the program.
@@ -4924,23 +4914,22 @@ namespace internal {
 UnitTestImpl::UnitTestImpl(UnitTest* parent)
     : parent_(parent),
       GTEST_DISABLE_MSC_WARNINGS_PUSH_(4355 /* using this in initializer */)
-      default_global_test_part_result_reporter_(this),
+          default_global_test_part_result_reporter_(this),
       default_per_thread_test_part_result_reporter_(this),
-      GTEST_DISABLE_MSC_WARNINGS_POP_()
-      global_test_part_result_repoter_(
+      GTEST_DISABLE_MSC_WARNINGS_POP_() global_test_part_result_repoter_(
           &default_global_test_part_result_reporter_),
       per_thread_test_part_result_reporter_(
           &default_per_thread_test_part_result_reporter_),
       parameterized_test_registry_(),
       parameterized_tests_registered_(false),
       last_death_test_case_(-1),
-      current_test_case_(NULL),
-      current_test_info_(NULL),
+      current_test_case_(nullptr),
+      current_test_info_(nullptr),
       ad_hoc_test_result_(),
-      os_stack_trace_getter_(NULL),
+      os_stack_trace_getter_(nullptr),
       post_flag_parse_init_performed_(false),
       random_seed_(0),  // Will be overridden by the flag before first use.
-      random_(0),  // Will be reseeded before first use.
+      random_(0),       // Will be reseeded before first use.
       start_timestamp_(0),
       elapsed_time_(0),
 #if GTEST_HAS_DEATH_TEST
@@ -4970,10 +4959,10 @@ void UnitTestImpl::RecordProperty(const TestProperty& test_property) {
   std::string xml_element;
   TestResult* test_result;  // TestResult appropriate for property recording.
 
-  if (current_test_info_ != NULL) {
+  if (current_test_info_ != nullptr) {
     xml_element = "testcase";
     test_result = &(current_test_info_->result_);
-  } else if (current_test_case_ != NULL) {
+  } else if (current_test_case_ != nullptr) {
     xml_element = "testsuite";
     test_result = &(current_test_case_->ad_hoc_test_result_);
   } else {
@@ -4987,7 +4976,7 @@ void UnitTestImpl::RecordProperty(const TestProperty& test_property) {
 // Disables event forwarding if the control is currently in a death test
 // subprocess. Must not be called before InitGoogleTest.
 void UnitTestImpl::SuppressTestEventsIfInSubprocess() {
-  if (internal_run_death_test_flag_.get() != NULL)
+  if (internal_run_death_test_flag_.get() != nullptr)
     listeners()->SuppressEventForwarding();
 }
 #endif  // GTEST_HAS_DEATH_TEST
@@ -5085,7 +5074,8 @@ class TestCaseNameIs {
 
   // Returns true iff the name of test_case matches name_.
   bool operator()(const TestCase* test_case) const {
-    return test_case != NULL && strcmp(test_case->name(), name_.c_str()) == 0;
+    return test_case != nullptr &&
+           strcmp(test_case->name(), name_.c_str()) == 0;
   }
 
  private:
@@ -5175,7 +5165,8 @@ bool UnitTestImpl::RunAllTests() {
   bool in_subprocess_for_death_test = false;
 
 #if GTEST_HAS_DEATH_TEST
-  in_subprocess_for_death_test = (internal_run_death_test_flag_.get() != NULL);
+  in_subprocess_for_death_test =
+      (internal_run_death_test_flag_.get() != nullptr);
 # if defined(GTEST_EXTRA_DEATH_TEST_CHILD_SETUP_)
   if (in_subprocess_for_death_test) {
     GTEST_EXTRA_DEATH_TEST_CHILD_SETUP_();
@@ -5306,9 +5297,9 @@ bool UnitTestImpl::RunAllTests() {
 // be created, prints an error and exits.
 void WriteToShardStatusFileIfNeeded() {
   const char* const test_shard_file = posix::GetEnv(kTestShardStatusFile);
-  if (test_shard_file != NULL) {
+  if (test_shard_file != nullptr) {
     FILE* const file = posix::FOpen(test_shard_file, "w");
-    if (file == NULL) {
+    if (file == nullptr) {
       ColoredPrintf(COLOR_RED,
                     "Could not write to the test shard status file \"%s\" "
                     "specified by the %s environment variable.\n",
@@ -5373,7 +5364,7 @@ bool ShouldShard(const char* total_shards_env,
 // and aborts.
 Int32 Int32FromEnvOrDie(const char* var, Int32 default_val) {
   const char* str_val = posix::GetEnv(var);
-  if (str_val == NULL) {
+  if (str_val == nullptr) {
     return default_val;
   }
 
@@ -5459,7 +5450,7 @@ int UnitTestImpl::FilterTests(ReactionToSharding shard_tests) {
 // max_length characters, only prints the first max_length characters
 // and "...".
 static void PrintOnOneLine(const char* str, int max_length) {
-  if (str != NULL) {
+  if (str != nullptr) {
     for (int i = 0; *str != '\0'; ++str) {
       if (i >= max_length) {
         printf("...");
@@ -5492,7 +5483,7 @@ void UnitTestImpl::ListTestsMatchingFilter() {
         if (!printed_test_case_name) {
           printed_test_case_name = true;
           printf("%s.", test_case->name());
-          if (test_case->type_param() != NULL) {
+          if (test_case->type_param() != nullptr) {
             printf("  # %s = ", kTypeParamLabel);
             // We print the type parameter on a single line to make
             // the output easy to parse by a program.
@@ -5501,7 +5492,7 @@ void UnitTestImpl::ListTestsMatchingFilter() {
           printf("\n");
         }
         printf("  %s", test_info->name());
-        if (test_info->value_param() != NULL) {
+        if (test_info->value_param() != nullptr) {
           printf("  # %s = ", kValueParamLabel);
           // We print the value parameter on a single line to make the
           // output easy to parse by a program.
@@ -5548,7 +5539,7 @@ void UnitTestImpl::set_os_stack_trace_getter(
 // otherwise, creates an OsStackTraceGetter, makes it the current
 // getter, and returns it.
 OsStackTraceGetterInterface* UnitTestImpl::os_stack_trace_getter() {
-  if (os_stack_trace_getter_ == NULL) {
+  if (os_stack_trace_getter_ == nullptr) {
 #ifdef GTEST_OS_STACK_TRACE_GETTER_
     os_stack_trace_getter_ = new GTEST_OS_STACK_TRACE_GETTER_;
 #else
@@ -5561,10 +5552,10 @@ OsStackTraceGetterInterface* UnitTestImpl::os_stack_trace_getter() {
 
 // Returns the most specific TestResult currently running.
 TestResult* UnitTestImpl::current_test_result() {
-  if (current_test_info_ != NULL) {
+  if (current_test_info_ != nullptr) {
     return &current_test_info_->result_;
   }
-  if (current_test_case_ != NULL) {
+  if (current_test_case_ != nullptr) {
     return &current_test_case_->ad_hoc_test_result_;
   }
   return &ad_hoc_test_result_;
@@ -5651,12 +5642,12 @@ bool SkipPrefix(const char* prefix, const char** pstr) {
 static const char* ParseFlagValue(const char* str, const char* flag,
                                   bool def_optional) {
   // str and flag must not be NULL.
-  if (str == NULL || flag == NULL) return NULL;
+  if (str == nullptr || flag == nullptr) return nullptr;
 
   // The flag must start with "--" followed by GTEST_FLAG_PREFIX_.
   const std::string flag_str = std::string("--") + GTEST_FLAG_PREFIX_ + flag;
   const size_t flag_len = flag_str.length();
-  if (strncmp(str, flag_str.c_str(), flag_len) != 0) return NULL;
+  if (strncmp(str, flag_str.c_str(), flag_len) != 0) return nullptr;
 
   // Skips the flag name.
   const char* flag_end = str + flag_len;
@@ -5669,7 +5660,7 @@ static const char* ParseFlagValue(const char* str, const char* flag,
   // If def_optional is true and there are more characters after the
   // flag name, or if def_optional is false, there must be a '=' after
   // the flag name.
-  if (flag_end[0] != '=') return NULL;
+  if (flag_end[0] != '=') return nullptr;
 
   // Returns the string after "=".
   return flag_end + 1;
@@ -5690,7 +5681,7 @@ static bool ParseBoolFlag(const char* str, const char* flag, bool* value) {
   const char* const value_str = ParseFlagValue(str, flag, true);
 
   // Aborts if the parsing failed.
-  if (value_str == NULL) return false;
+  if (value_str == nullptr) return false;
 
   // Converts the string value to a bool.
   *value = !(*value_str == '0' || *value_str == 'f' || *value_str == 'F');
@@ -5707,7 +5698,7 @@ bool ParseInt32Flag(const char* str, const char* flag, Int32* value) {
   const char* const value_str = ParseFlagValue(str, flag, false);
 
   // Aborts if the parsing failed.
-  if (value_str == NULL) return false;
+  if (value_str == nullptr) return false;
 
   // Sets *value to the value of the flag.
   return ParseInt32(Message() << "The value of flag --" << flag,
@@ -5725,7 +5716,7 @@ static bool ParseStringFlag(const char* str, const char* flag, String* value) {
   const char* const value_str = ParseFlagValue(str, flag, false);
 
   // Aborts if the parsing failed.
-  if (value_str == NULL) return false;
+  if (value_str == nullptr) return false;
 
   // Sets *value to the value of the flag.
   *value = value_str;
@@ -5767,7 +5758,7 @@ static void PrintColorEncoded(const char* str) {
   // next segment.
   for (;;) {
     const char* p = strchr(str, '@');
-    if (p == NULL) {
+    if (p == nullptr) {
       ColoredPrintf(color, "%s", str);
       return;
     }