diff --git a/googletest/include/gtest/gtest-printers.h b/googletest/include/gtest/gtest-printers.h
index e53963b4..373946b9 100644
--- a/googletest/include/gtest/gtest-printers.h
+++ b/googletest/include/gtest/gtest-printers.h
@@ -1,1078 +1,1082 @@
 // Copyright 2007, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 //
 // Author: wan@google.com (Zhanyong Wan)
 
 // Google Test - The Google C++ Testing and Mocking Framework
 //
 // This file implements a universal value printer that can print a
 // value of any type T:
 //
 //   void ::testing::internal::UniversalPrinter<T>::Print(value, ostream_ptr);
 //
 // A user can teach this function how to print a class type T by
 // defining either operator<<() or PrintTo() in the namespace that
 // defines T.  More specifically, the FIRST defined function in the
 // following list will be used (assuming T is defined in namespace
 // foo):
 //
 //   1. foo::PrintTo(const T&, ostream*)
 //   2. operator<<(ostream&, const T&) defined in either foo or the
 //      global namespace.
 //
 // However if T is an STL-style container then it is printed element-wise
 // unless foo::PrintTo(const T&, ostream*) is defined. Note that
 // operator<<() is ignored for container types.
 //
 // If none of the above is defined, it will print the debug string of
 // the value if it is a protocol buffer, or print the raw bytes in the
 // value otherwise.
 //
 // To aid debugging: when T is a reference type, the address of the
 // value is also printed; when T is a (const) char pointer, both the
 // pointer value and the NUL-terminated string it points to are
 // printed.
 //
 // We also provide some convenient wrappers:
 //
 //   // Prints a value to a string.  For a (const or not) char
 //   // pointer, the NUL-terminated string (but not the pointer) is
 //   // printed.
 //   std::string ::testing::PrintToString(const T& value);
 //
 //   // Prints a value tersely: for a reference type, the referenced
 //   // value (but not the address) is printed; for a (const or not) char
 //   // pointer, the NUL-terminated string (but not the pointer) is
 //   // printed.
 //   void ::testing::internal::UniversalTersePrint(const T& value, ostream*);
 //
 //   // Prints value using the type inferred by the compiler.  The difference
 //   // from UniversalTersePrint() is that this function prints both the
 //   // pointer and the NUL-terminated string for a (const or not) char pointer.
 //   void ::testing::internal::UniversalPrint(const T& value, ostream*);
 //
 //   // Prints the fields of a tuple tersely to a string vector, one
 //   // element for each field. Tuple support must be enabled in
 //   // gtest-port.h.
 //   std::vector<string> UniversalTersePrintTupleFieldsToStrings(
 //       const Tuple& value);
 //
 // Known limitation:
 //
 // The print primitives print the elements of an STL-style container
 // using the compiler-inferred type of *iter where iter is a
 // const_iterator of the container.  When const_iterator is an input
 // iterator but not a forward iterator, this inferred type may not
 // match value_type, and the print output may be incorrect.  In
 // practice, this is rarely a problem as for most containers
 // const_iterator is a forward iterator.  We'll fix this if there's an
 // actual need for it.  Note that this fix cannot rely on value_type
 // being defined as many user-defined container types don't have
 // value_type.
 
 #ifndef GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
 #define GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
 
 #include <ostream>  // NOLINT
 #include <sstream>
 #include <string>
 #include <utility>
 #include <vector>
 #include "gtest/internal/gtest-port.h"
 #include "gtest/internal/gtest-internal.h"
 
 #if GTEST_HAS_STD_TUPLE_
 # include <tuple>
 #endif
 
 #if GTEST_HAS_ABSL
 #include "absl/strings/string_view.h"
 #include "absl/types/optional.h"
 #endif  // GTEST_HAS_ABSL
 
 namespace testing {
 
 // Definitions in the 'internal' and 'internal2' name spaces are
 // subject to change without notice.  DO NOT USE THEM IN USER CODE!
 namespace internal2 {
 
 // Prints the given number of bytes in the given object to the given
 // ostream.
 GTEST_API_ void PrintBytesInObjectTo(const unsigned char* obj_bytes,
                                      size_t count,
                                      ::std::ostream* os);
 
 // For selecting which printer to use when a given type has neither <<
 // nor PrintTo().
 enum TypeKind {
   kProtobuf,              // a protobuf type
   kConvertibleToInteger,  // a type implicitly convertible to BiggestInt
                           // (e.g. a named or unnamed enum type)
 #if GTEST_HAS_ABSL
   kConvertibleToStringView,  // a type implicitly convertible to
                              // absl::string_view
 #endif
   kOtherType  // anything else
 };
 
 // TypeWithoutFormatter<T, kTypeKind>::PrintValue(value, os) is called
 // by the universal printer to print a value of type T when neither
 // operator<< nor PrintTo() is defined for T, where kTypeKind is the
 // "kind" of T as defined by enum TypeKind.
 template <typename T, TypeKind kTypeKind>
 class TypeWithoutFormatter {
  public:
   // This default version is called when kTypeKind is kOtherType.
   static void PrintValue(const T& value, ::std::ostream* os) {
     PrintBytesInObjectTo(static_cast<const unsigned char*>(
                              reinterpret_cast<const void*>(&value)),
                          sizeof(value), os);
   }
 };
 
 // We print a protobuf using its ShortDebugString() when the string
 // doesn't exceed this many characters; otherwise we print it using
 // DebugString() for better readability.
 const size_t kProtobufOneLinerMaxLength = 50;
 
 template <typename T>
 class TypeWithoutFormatter<T, kProtobuf> {
  public:
   static void PrintValue(const T& value, ::std::ostream* os) {
     std::string pretty_str = value.ShortDebugString();
     if (pretty_str.length() > kProtobufOneLinerMaxLength) {
       pretty_str = "\n" + value.DebugString();
     }
     *os << ("<" + pretty_str + ">");
   }
 };
 
 template <typename T>
 class TypeWithoutFormatter<T, kConvertibleToInteger> {
  public:
   // Since T has no << operator or PrintTo() but can be implicitly
   // converted to BiggestInt, we print it as a BiggestInt.
   //
   // Most likely T is an enum type (either named or unnamed), in which
   // case printing it as an integer is the desired behavior.  In case
   // T is not an enum, printing it as an integer is the best we can do
   // given that it has no user-defined printer.
   static void PrintValue(const T& value, ::std::ostream* os) {
     const internal::BiggestInt kBigInt = value;
     *os << kBigInt;
   }
 };
 
 #if GTEST_HAS_ABSL
 template <typename T>
 class TypeWithoutFormatter<T, kConvertibleToStringView> {
  public:
   // Since T has neither operator<< nor PrintTo() but can be implicitly
   // converted to absl::string_view, we print it as a absl::string_view.
   //
   // Note: the implementation is further below, as it depends on
   // internal::PrintTo symbol which is defined later in the file.
   static void PrintValue(const T& value, ::std::ostream* os);
 };
 #endif
 
 // Prints the given value to the given ostream.  If the value is a
 // protocol message, its debug string is printed; if it's an enum or
 // of a type implicitly convertible to BiggestInt, it's printed as an
 // integer; otherwise the bytes in the value are printed.  This is
 // what UniversalPrinter<T>::Print() does when it knows nothing about
 // type T and T has neither << operator nor PrintTo().
 //
 // A user can override this behavior for a class type Foo by defining
 // a << operator in the namespace where Foo is defined.
 //
 // We put this operator in namespace 'internal2' instead of 'internal'
 // to simplify the implementation, as much code in 'internal' needs to
 // use << in STL, which would conflict with our own << were it defined
 // in 'internal'.
 //
 // Note that this operator<< takes a generic std::basic_ostream<Char,
 // CharTraits> type instead of the more restricted std::ostream.  If
 // we define it to take an std::ostream instead, we'll get an
 // "ambiguous overloads" compiler error when trying to print a type
 // Foo that supports streaming to std::basic_ostream<Char,
 // CharTraits>, as the compiler cannot tell whether
 // operator<<(std::ostream&, const T&) or
 // operator<<(std::basic_stream<Char, CharTraits>, const Foo&) is more
 // specific.
 template <typename Char, typename CharTraits, typename T>
 ::std::basic_ostream<Char, CharTraits>& operator<<(
     ::std::basic_ostream<Char, CharTraits>& os, const T& x) {
   TypeWithoutFormatter<T, (internal::IsAProtocolMessage<T>::value
                                ? kProtobuf
                                : internal::ImplicitlyConvertible<
                                      const T&, internal::BiggestInt>::value
                                      ? kConvertibleToInteger
                                      :
 #if GTEST_HAS_ABSL
                                      internal::ImplicitlyConvertible<
                                          const T&, absl::string_view>::value
                                          ? kConvertibleToStringView
                                          :
 #endif
                                          kOtherType)>::PrintValue(x, &os);
   return os;
 }
 
 }  // namespace internal2
 }  // namespace testing
 
 // This namespace MUST NOT BE NESTED IN ::testing, or the name look-up
 // magic needed for implementing UniversalPrinter won't work.
 namespace testing_internal {
 
 // Used to print a value that is not an STL-style container when the
 // user doesn't define PrintTo() for it.
 template <typename T>
 void DefaultPrintNonContainerTo(const T& value, ::std::ostream* os) {
   // With the following statement, during unqualified name lookup,
   // testing::internal2::operator<< appears as if it was declared in
   // the nearest enclosing namespace that contains both
   // ::testing_internal and ::testing::internal2, i.e. the global
   // namespace.  For more details, refer to the C++ Standard section
   // 7.3.4-1 [namespace.udir].  This allows us to fall back onto
   // testing::internal2::operator<< in case T doesn't come with a <<
   // operator.
   //
   // We cannot write 'using ::testing::internal2::operator<<;', which
   // gcc 3.3 fails to compile due to a compiler bug.
   using namespace ::testing::internal2;  // NOLINT
 
   // Assuming T is defined in namespace foo, in the next statement,
   // the compiler will consider all of:
   //
   //   1. foo::operator<< (thanks to Koenig look-up),
   //   2. ::operator<< (as the current namespace is enclosed in ::),
   //   3. testing::internal2::operator<< (thanks to the using statement above).
   //
   // The operator<< whose type matches T best will be picked.
   //
   // We deliberately allow #2 to be a candidate, as sometimes it's
   // impossible to define #1 (e.g. when foo is ::std, defining
   // anything in it is undefined behavior unless you are a compiler
   // vendor.).
   *os << value;
 }
 
 }  // namespace testing_internal
 
 namespace testing {
 namespace internal {
 
 // FormatForComparison<ToPrint, OtherOperand>::Format(value) formats a
 // value of type ToPrint that is an operand of a comparison assertion
 // (e.g. ASSERT_EQ).  OtherOperand is the type of the other operand in
 // the comparison, and is used to help determine the best way to
 // format the value.  In particular, when the value is a C string
 // (char pointer) and the other operand is an STL string object, we
 // want to format the C string as a string, since we know it is
 // compared by value with the string object.  If the value is a char
 // pointer but the other operand is not an STL string object, we don't
 // know whether the pointer is supposed to point to a NUL-terminated
 // string, and thus want to print it as a pointer to be safe.
 //
 // INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM.
 
 // The default case.
 template <typename ToPrint, typename OtherOperand>
 class FormatForComparison {
  public:
   static ::std::string Format(const ToPrint& value) {
     return ::testing::PrintToString(value);
   }
 };
 
 // Array.
 template <typename ToPrint, size_t N, typename OtherOperand>
 class FormatForComparison<ToPrint[N], OtherOperand> {
  public:
   static ::std::string Format(const ToPrint* value) {
     return FormatForComparison<const ToPrint*, OtherOperand>::Format(value);
   }
 };
 
 // By default, print C string as pointers to be safe, as we don't know
 // whether they actually point to a NUL-terminated string.
 
 #define GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(CharType)                \
   template <typename OtherOperand>                                      \
   class FormatForComparison<CharType*, OtherOperand> {                  \
    public:                                                              \
     static ::std::string Format(CharType* value) {                      \
       return ::testing::PrintToString(static_cast<const void*>(value)); \
     }                                                                   \
   }
 
 GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char);
 GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char);
 GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(wchar_t);
 GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const wchar_t);
 
 #undef GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_
 
 // If a C string is compared with an STL string object, we know it's meant
 // to point to a NUL-terminated string, and thus can print it as a string.
 
 #define GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(CharType, OtherStringType) \
   template <>                                                           \
   class FormatForComparison<CharType*, OtherStringType> {               \
    public:                                                              \
     static ::std::string Format(CharType* value) {                      \
       return ::testing::PrintToString(value);                           \
     }                                                                   \
   }
 
 GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char, ::std::string);
 GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char, ::std::string);
 
 #if GTEST_HAS_GLOBAL_STRING
 GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char, ::string);
 GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char, ::string);
 #endif
 
 #if GTEST_HAS_GLOBAL_WSTRING
 GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(wchar_t, ::wstring);
 GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const wchar_t, ::wstring);
 #endif
 
 #if GTEST_HAS_STD_WSTRING
 GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(wchar_t, ::std::wstring);
 GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const wchar_t, ::std::wstring);
 #endif
 
 #undef GTEST_IMPL_FORMAT_C_STRING_AS_STRING_
 
 // Formats a comparison assertion (e.g. ASSERT_EQ, EXPECT_LT, and etc)
 // operand to be used in a failure message.  The type (but not value)
 // of the other operand may affect the format.  This allows us to
 // print a char* as a raw pointer when it is compared against another
 // char* or void*, and print it as a C string when it is compared
 // against an std::string object, for example.
 //
 // INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM.
 template <typename T1, typename T2>
 std::string FormatForComparisonFailureMessage(
     const T1& value, const T2& /* other_operand */) {
   return FormatForComparison<T1, T2>::Format(value);
 }
 
 // UniversalPrinter<T>::Print(value, ostream_ptr) prints the given
 // value to the given ostream.  The caller must ensure that
 // 'ostream_ptr' is not NULL, or the behavior is undefined.
 //
 // We define UniversalPrinter as a class template (as opposed to a
 // function template), as we need to partially specialize it for
 // reference types, which cannot be done with function templates.
 template <typename T>
 class UniversalPrinter;
 
 template <typename T>
 void UniversalPrint(const T& value, ::std::ostream* os);
 
 enum DefaultPrinterType {
   kPrintContainer,
   kPrintPointer,
   kPrintFunctionPointer,
   kPrintOther,
 };
 template <DefaultPrinterType type> struct WrapPrinterType {};
 
 // Used to print an STL-style container when the user doesn't define
 // a PrintTo() for it.
 template <typename C>
 void DefaultPrintTo(WrapPrinterType<kPrintContainer> /* dummy */,
                     const C& container, ::std::ostream* os) {
   const size_t kMaxCount = 32;  // The maximum number of elements to print.
   *os << '{';
   size_t count = 0;
   for (typename C::const_iterator it = container.begin();
        it != container.end(); ++it, ++count) {
     if (count > 0) {
       *os << ',';
       if (count == kMaxCount) {  // Enough has been printed.
         *os << " ...";
         break;
       }
     }
     *os << ' ';
     // We cannot call PrintTo(*it, os) here as PrintTo() doesn't
     // handle *it being a native array.
     internal::UniversalPrint(*it, os);
   }
 
   if (count > 0) {
     *os << ' ';
   }
   *os << '}';
 }
 
 // Used to print a pointer that is neither a char pointer nor a member
 // pointer, when the user doesn't define PrintTo() for it.  (A member
 // variable pointer or member function pointer doesn't really point to
 // a location in the address space.  Their representation is
 // implementation-defined.  Therefore they will be printed as raw
 // bytes.)
 template <typename T>
 void DefaultPrintTo(WrapPrinterType<kPrintPointer> /* dummy */,
                     T* p, ::std::ostream* os) {
   if (p == NULL) {
     *os << "NULL";
   } else {
     // T is not a function type.  We just call << to print p,
     // relying on ADL to pick up user-defined << for their pointer
     // types, if any.
     *os << p;
   }
 }
 template <typename T>
 void DefaultPrintTo(WrapPrinterType<kPrintFunctionPointer> /* dummy */,
                     T* p, ::std::ostream* os) {
   if (p == NULL) {
     *os << "NULL";
   } else {
     // T is a function type, so '*os << p' doesn't do what we want
     // (it just prints p as bool).  We want to print p as a const
     // void*.
     *os << reinterpret_cast<const void*>(p);
   }
 }
 
 // Used to print a non-container, non-pointer value when the user
 // doesn't define PrintTo() for it.
 template <typename T>
 void DefaultPrintTo(WrapPrinterType<kPrintOther> /* dummy */,
                     const T& value, ::std::ostream* os) {
   ::testing_internal::DefaultPrintNonContainerTo(value, os);
 }
 
 // Prints the given value using the << operator if it has one;
 // otherwise prints the bytes in it.  This is what
 // UniversalPrinter<T>::Print() does when PrintTo() is not specialized
 // or overloaded for type T.
 //
 // A user can override this behavior for a class type Foo by defining
 // an overload of PrintTo() in the namespace where Foo is defined.  We
 // give the user this option as sometimes defining a << operator for
 // Foo is not desirable (e.g. the coding style may prevent doing it,
 // or there is already a << operator but it doesn't do what the user
 // wants).
 template <typename T>
 void PrintTo(const T& value, ::std::ostream* os) {
   // DefaultPrintTo() is overloaded.  The type of its first argument
   // determines which version will be picked.
   //
   // Note that we check for container types here, prior to we check
   // for protocol message types in our operator<<.  The rationale is:
   //
   // For protocol messages, we want to give people a chance to
   // override Google Mock's format by defining a PrintTo() or
   // operator<<.  For STL containers, other formats can be
   // incompatible with Google Mock's format for the container
   // elements; therefore we check for container types here to ensure
   // that our format is used.
   //
   // Note that MSVC and clang-cl do allow an implicit conversion from
   // pointer-to-function to pointer-to-object, but clang-cl warns on it.
   // So don't use ImplicitlyConvertible if it can be helped since it will
   // cause this warning, and use a separate overload of DefaultPrintTo for
   // function pointers so that the `*os << p` in the object pointer overload
   // doesn't cause that warning either.
   DefaultPrintTo(
       WrapPrinterType <
                   (sizeof(IsContainerTest<T>(0)) == sizeof(IsContainer)) &&
               !IsRecursiveContainer<T>::value
           ? kPrintContainer
           : !is_pointer<T>::value
                 ? kPrintOther
 #if GTEST_LANG_CXX11
                 : std::is_function<typename std::remove_pointer<T>::type>::value
 #else
                 : !internal::ImplicitlyConvertible<T, const void*>::value
 #endif
                       ? kPrintFunctionPointer
                       : kPrintPointer > (),
       value, os);
 }
 
 // The following list of PrintTo() overloads tells
 // UniversalPrinter<T>::Print() how to print standard types (built-in
 // types, strings, plain arrays, and pointers).
 
 // Overloads for various char types.
 GTEST_API_ void PrintTo(unsigned char c, ::std::ostream* os);
 GTEST_API_ void PrintTo(signed char c, ::std::ostream* os);
 inline void PrintTo(char c, ::std::ostream* os) {
   // When printing a plain char, we always treat it as unsigned.  This
   // way, the output won't be affected by whether the compiler thinks
   // char is signed or not.
   PrintTo(static_cast<unsigned char>(c), os);
 }
 
 // Overloads for other simple built-in types.
 inline void PrintTo(bool x, ::std::ostream* os) {
   *os << (x ? "true" : "false");
 }
 
 // Overload for wchar_t type.
 // Prints a wchar_t as a symbol if it is printable or as its internal
 // code otherwise and also as its decimal code (except for L'\0').
 // The L'\0' char is printed as "L'\\0'". The decimal code is printed
 // as signed integer when wchar_t is implemented by the compiler
 // as a signed type and is printed as an unsigned integer when wchar_t
 // is implemented as an unsigned type.
 GTEST_API_ void PrintTo(wchar_t wc, ::std::ostream* os);
 
 // Overloads for C strings.
 GTEST_API_ void PrintTo(const char* s, ::std::ostream* os);
 inline void PrintTo(char* s, ::std::ostream* os) {
   PrintTo(ImplicitCast_<const char*>(s), os);
 }
 
 // signed/unsigned char is often used for representing binary data, so
 // we print pointers to it as void* to be safe.
 inline void PrintTo(const signed char* s, ::std::ostream* os) {
   PrintTo(ImplicitCast_<const void*>(s), os);
 }
 inline void PrintTo(signed char* s, ::std::ostream* os) {
   PrintTo(ImplicitCast_<const void*>(s), os);
 }
 inline void PrintTo(const unsigned char* s, ::std::ostream* os) {
   PrintTo(ImplicitCast_<const void*>(s), os);
 }
 inline void PrintTo(unsigned char* s, ::std::ostream* os) {
   PrintTo(ImplicitCast_<const void*>(s), os);
 }
 
 // MSVC can be configured to define wchar_t as a typedef of unsigned
 // short.  It defines _NATIVE_WCHAR_T_DEFINED when wchar_t is a native
 // type.  When wchar_t is a typedef, defining an overload for const
 // wchar_t* would cause unsigned short* be printed as a wide string,
 // possibly causing invalid memory accesses.
 #if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
 // Overloads for wide C strings
 GTEST_API_ void PrintTo(const wchar_t* s, ::std::ostream* os);
 inline void PrintTo(wchar_t* s, ::std::ostream* os) {
   PrintTo(ImplicitCast_<const wchar_t*>(s), os);
 }
 #endif
 
 // Overload for C arrays.  Multi-dimensional arrays are printed
 // properly.
 
 // Prints the given number of elements in an array, without printing
 // the curly braces.
 template <typename T>
 void PrintRawArrayTo(const T a[], size_t count, ::std::ostream* os) {
   UniversalPrint(a[0], os);
   for (size_t i = 1; i != count; i++) {
     *os << ", ";
     UniversalPrint(a[i], os);
   }
 }
 
 // Overloads for ::string and ::std::string.
 #if GTEST_HAS_GLOBAL_STRING
 GTEST_API_ void PrintStringTo(const ::string&s, ::std::ostream* os);
 inline void PrintTo(const ::string& s, ::std::ostream* os) {
   PrintStringTo(s, os);
 }
 #endif  // GTEST_HAS_GLOBAL_STRING
 
 GTEST_API_ void PrintStringTo(const ::std::string&s, ::std::ostream* os);
 inline void PrintTo(const ::std::string& s, ::std::ostream* os) {
   PrintStringTo(s, os);
 }
 
 // Overloads for ::wstring and ::std::wstring.
 #if GTEST_HAS_GLOBAL_WSTRING
 GTEST_API_ void PrintWideStringTo(const ::wstring&s, ::std::ostream* os);
 inline void PrintTo(const ::wstring& s, ::std::ostream* os) {
   PrintWideStringTo(s, os);
 }
 #endif  // GTEST_HAS_GLOBAL_WSTRING
 
 #if GTEST_HAS_STD_WSTRING
 GTEST_API_ void PrintWideStringTo(const ::std::wstring&s, ::std::ostream* os);
 inline void PrintTo(const ::std::wstring& s, ::std::ostream* os) {
   PrintWideStringTo(s, os);
 }
 #endif  // GTEST_HAS_STD_WSTRING
 
 #if GTEST_HAS_ABSL
 // Overload for absl::string_view.
 inline void PrintTo(absl::string_view sp, ::std::ostream* os) {
   PrintTo(::std::string(sp), os);
 }
 #endif  // GTEST_HAS_ABSL
 
+#if GTEST_LANG_CXX11
+inline void PrintTo(std::nullptr_t, ::std::ostream* os) { *os << "(nullptr)"; }
+#endif  // GTEST_LANG_CXX11
+
 #if GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_
 // Helper function for printing a tuple.  T must be instantiated with
 // a tuple type.
 template <typename T>
 void PrintTupleTo(const T& t, ::std::ostream* os);
 #endif  // GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_
 
 #if GTEST_HAS_TR1_TUPLE
 // Overload for ::std::tr1::tuple.  Needed for printing function arguments,
 // which are packed as tuples.
 
 // Overloaded PrintTo() for tuples of various arities.  We support
 // tuples of up-to 10 fields.  The following implementation works
 // regardless of whether tr1::tuple is implemented using the
 // non-standard variadic template feature or not.
 
 inline void PrintTo(const ::std::tr1::tuple<>& t, ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1>
 void PrintTo(const ::std::tr1::tuple<T1>& t, ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2>
 void PrintTo(const ::std::tr1::tuple<T1, T2>& t, ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2, typename T3>
 void PrintTo(const ::std::tr1::tuple<T1, T2, T3>& t, ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2, typename T3, typename T4>
 void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4>& t, ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2, typename T3, typename T4, typename T5>
 void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5>& t,
              ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2, typename T3, typename T4, typename T5,
           typename T6>
 void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6>& t,
              ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2, typename T3, typename T4, typename T5,
           typename T6, typename T7>
 void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7>& t,
              ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2, typename T3, typename T4, typename T5,
           typename T6, typename T7, typename T8>
 void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8>& t,
              ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2, typename T3, typename T4, typename T5,
           typename T6, typename T7, typename T8, typename T9>
 void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8, T9>& t,
              ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 
 template <typename T1, typename T2, typename T3, typename T4, typename T5,
           typename T6, typename T7, typename T8, typename T9, typename T10>
 void PrintTo(
     const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>& t,
     ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 #endif  // GTEST_HAS_TR1_TUPLE
 
 #if GTEST_HAS_STD_TUPLE_
 template <typename... Types>
 void PrintTo(const ::std::tuple<Types...>& t, ::std::ostream* os) {
   PrintTupleTo(t, os);
 }
 #endif  // GTEST_HAS_STD_TUPLE_
 
 // Overload for std::pair.
 template <typename T1, typename T2>
 void PrintTo(const ::std::pair<T1, T2>& value, ::std::ostream* os) {
   *os << '(';
   // We cannot use UniversalPrint(value.first, os) here, as T1 may be
   // a reference type.  The same for printing value.second.
   UniversalPrinter<T1>::Print(value.first, os);
   *os << ", ";
   UniversalPrinter<T2>::Print(value.second, os);
   *os << ')';
 }
 
 // Implements printing a non-reference type T by letting the compiler
 // pick the right overload of PrintTo() for T.
 template <typename T>
 class UniversalPrinter {
  public:
   // MSVC warns about adding const to a function type, so we want to
   // disable the warning.
   GTEST_DISABLE_MSC_WARNINGS_PUSH_(4180)
 
   // Note: we deliberately don't call this PrintTo(), as that name
   // conflicts with ::testing::internal::PrintTo in the body of the
   // function.
   static void Print(const T& value, ::std::ostream* os) {
     // By default, ::testing::internal::PrintTo() is used for printing
     // the value.
     //
     // Thanks to Koenig look-up, if T is a class and has its own
     // PrintTo() function defined in its namespace, that function will
     // be visible here.  Since it is more specific than the generic ones
     // in ::testing::internal, it will be picked by the compiler in the
     // following statement - exactly what we want.
     PrintTo(value, os);
   }
 
   GTEST_DISABLE_MSC_WARNINGS_POP_()
 };
 
 #if GTEST_HAS_ABSL
 
 // Printer for absl::optional
 
 template <typename T>
 class UniversalPrinter<::absl::optional<T>> {
  public:
   static void Print(const ::absl::optional<T>& value, ::std::ostream* os) {
     *os << '(';
     if (!value) {
       *os << "nullopt";
     } else {
       UniversalPrint(*value, os);
     }
     *os << ')';
   }
 };
 
 #endif  // GTEST_HAS_ABSL
 
 // UniversalPrintArray(begin, len, os) prints an array of 'len'
 // elements, starting at address 'begin'.
 template <typename T>
 void UniversalPrintArray(const T* begin, size_t len, ::std::ostream* os) {
   if (len == 0) {
     *os << "{}";
   } else {
     *os << "{ ";
     const size_t kThreshold = 18;
     const size_t kChunkSize = 8;
     // If the array has more than kThreshold elements, we'll have to
     // omit some details by printing only the first and the last
     // kChunkSize elements.
     // TODO(wan@google.com): let the user control the threshold using a flag.
     if (len <= kThreshold) {
       PrintRawArrayTo(begin, len, os);
     } else {
       PrintRawArrayTo(begin, kChunkSize, os);
       *os << ", ..., ";
       PrintRawArrayTo(begin + len - kChunkSize, kChunkSize, os);
     }
     *os << " }";
   }
 }
 // This overload prints a (const) char array compactly.
 GTEST_API_ void UniversalPrintArray(
     const char* begin, size_t len, ::std::ostream* os);
 
 // This overload prints a (const) wchar_t array compactly.
 GTEST_API_ void UniversalPrintArray(
     const wchar_t* begin, size_t len, ::std::ostream* os);
 
 // Implements printing an array type T[N].
 template <typename T, size_t N>
 class UniversalPrinter<T[N]> {
  public:
   // Prints the given array, omitting some elements when there are too
   // many.
   static void Print(const T (&a)[N], ::std::ostream* os) {
     UniversalPrintArray(a, N, os);
   }
 };
 
 // Implements printing a reference type T&.
 template <typename T>
 class UniversalPrinter<T&> {
  public:
   // MSVC warns about adding const to a function type, so we want to
   // disable the warning.
   GTEST_DISABLE_MSC_WARNINGS_PUSH_(4180)
 
   static void Print(const T& value, ::std::ostream* os) {
     // Prints the address of the value.  We use reinterpret_cast here
     // as static_cast doesn't compile when T is a function type.
     *os << "@" << reinterpret_cast<const void*>(&value) << " ";
 
     // Then prints the value itself.
     UniversalPrint(value, os);
   }
 
   GTEST_DISABLE_MSC_WARNINGS_POP_()
 };
 
 // Prints a value tersely: for a reference type, the referenced value
 // (but not the address) is printed; for a (const) char pointer, the
 // NUL-terminated string (but not the pointer) is printed.
 
 template <typename T>
 class UniversalTersePrinter {
  public:
   static void Print(const T& value, ::std::ostream* os) {
     UniversalPrint(value, os);
   }
 };
 template <typename T>
 class UniversalTersePrinter<T&> {
  public:
   static void Print(const T& value, ::std::ostream* os) {
     UniversalPrint(value, os);
   }
 };
 template <typename T, size_t N>
 class UniversalTersePrinter<T[N]> {
  public:
   static void Print(const T (&value)[N], ::std::ostream* os) {
     UniversalPrinter<T[N]>::Print(value, os);
   }
 };
 template <>
 class UniversalTersePrinter<const char*> {
  public:
   static void Print(const char* str, ::std::ostream* os) {
     if (str == NULL) {
       *os << "NULL";
     } else {
       UniversalPrint(std::string(str), os);
     }
   }
 };
 template <>
 class UniversalTersePrinter<char*> {
  public:
   static void Print(char* str, ::std::ostream* os) {
     UniversalTersePrinter<const char*>::Print(str, os);
   }
 };
 
 #if GTEST_HAS_STD_WSTRING
 template <>
 class UniversalTersePrinter<const wchar_t*> {
  public:
   static void Print(const wchar_t* str, ::std::ostream* os) {
     if (str == NULL) {
       *os << "NULL";
     } else {
       UniversalPrint(::std::wstring(str), os);
     }
   }
 };
 #endif
 
 template <>
 class UniversalTersePrinter<wchar_t*> {
  public:
   static void Print(wchar_t* str, ::std::ostream* os) {
     UniversalTersePrinter<const wchar_t*>::Print(str, os);
   }
 };
 
 template <typename T>
 void UniversalTersePrint(const T& value, ::std::ostream* os) {
   UniversalTersePrinter<T>::Print(value, os);
 }
 
 // Prints a value using the type inferred by the compiler.  The
 // difference between this and UniversalTersePrint() is that for a
 // (const) char pointer, this prints both the pointer and the
 // NUL-terminated string.
 template <typename T>
 void UniversalPrint(const T& value, ::std::ostream* os) {
   // A workarond for the bug in VC++ 7.1 that prevents us from instantiating
   // UniversalPrinter with T directly.
   typedef T T1;
   UniversalPrinter<T1>::Print(value, os);
 }
 
 typedef ::std::vector< ::std::string> Strings;
 
 // TuplePolicy<TupleT> must provide:
 // - tuple_size
 //     size of tuple TupleT.
 // - get<size_t I>(const TupleT& t)
 //     static function extracting element I of tuple TupleT.
 // - tuple_element<size_t I>::type
 //     type of element I of tuple TupleT.
 template <typename TupleT>
 struct TuplePolicy;
 
 #if GTEST_HAS_TR1_TUPLE
 template <typename TupleT>
 struct TuplePolicy {
   typedef TupleT Tuple;
   static const size_t tuple_size = ::std::tr1::tuple_size<Tuple>::value;
 
   template <size_t I>
   struct tuple_element : ::std::tr1::tuple_element<I, Tuple> {};
 
   template <size_t I>
   static typename AddReference<
       const typename ::std::tr1::tuple_element<I, Tuple>::type>::type get(
       const Tuple& tuple) {
     return ::std::tr1::get<I>(tuple);
   }
 };
 template <typename TupleT>
 const size_t TuplePolicy<TupleT>::tuple_size;
 #endif  // GTEST_HAS_TR1_TUPLE
 
 #if GTEST_HAS_STD_TUPLE_
 template <typename... Types>
 struct TuplePolicy< ::std::tuple<Types...> > {
   typedef ::std::tuple<Types...> Tuple;
   static const size_t tuple_size = ::std::tuple_size<Tuple>::value;
 
   template <size_t I>
   struct tuple_element : ::std::tuple_element<I, Tuple> {};
 
   template <size_t I>
   static const typename ::std::tuple_element<I, Tuple>::type& get(
       const Tuple& tuple) {
     return ::std::get<I>(tuple);
   }
 };
 template <typename... Types>
 const size_t TuplePolicy< ::std::tuple<Types...> >::tuple_size;
 #endif  // GTEST_HAS_STD_TUPLE_
 
 #if GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_
 // This helper template allows PrintTo() for tuples and
 // UniversalTersePrintTupleFieldsToStrings() to be defined by
 // induction on the number of tuple fields.  The idea is that
 // TuplePrefixPrinter<N>::PrintPrefixTo(t, os) prints the first N
 // fields in tuple t, and can be defined in terms of
 // TuplePrefixPrinter<N - 1>.
 //
 // The inductive case.
 template <size_t N>
 struct TuplePrefixPrinter {
   // Prints the first N fields of a tuple.
   template <typename Tuple>
   static void PrintPrefixTo(const Tuple& t, ::std::ostream* os) {
     TuplePrefixPrinter<N - 1>::PrintPrefixTo(t, os);
     GTEST_INTENTIONAL_CONST_COND_PUSH_()
     if (N > 1) {
     GTEST_INTENTIONAL_CONST_COND_POP_()
       *os << ", ";
     }
     UniversalPrinter<
         typename TuplePolicy<Tuple>::template tuple_element<N - 1>::type>
         ::Print(TuplePolicy<Tuple>::template get<N - 1>(t), os);
   }
 
   // Tersely prints the first N fields of a tuple to a string vector,
   // one element for each field.
   template <typename Tuple>
   static void TersePrintPrefixToStrings(const Tuple& t, Strings* strings) {
     TuplePrefixPrinter<N - 1>::TersePrintPrefixToStrings(t, strings);
     ::std::stringstream ss;
     UniversalTersePrint(TuplePolicy<Tuple>::template get<N - 1>(t), &ss);
     strings->push_back(ss.str());
   }
 };
 
 // Base case.
 template <>
 struct TuplePrefixPrinter<0> {
   template <typename Tuple>
   static void PrintPrefixTo(const Tuple&, ::std::ostream*) {}
 
   template <typename Tuple>
   static void TersePrintPrefixToStrings(const Tuple&, Strings*) {}
 };
 
 // Helper function for printing a tuple.
 // Tuple must be either std::tr1::tuple or std::tuple type.
 template <typename Tuple>
 void PrintTupleTo(const Tuple& t, ::std::ostream* os) {
   *os << "(";
   TuplePrefixPrinter<TuplePolicy<Tuple>::tuple_size>::PrintPrefixTo(t, os);
   *os << ")";
 }
 
 // Prints the fields of a tuple tersely to a string vector, one
 // element for each field.  See the comment before
 // UniversalTersePrint() for how we define "tersely".
 template <typename Tuple>
 Strings UniversalTersePrintTupleFieldsToStrings(const Tuple& value) {
   Strings result;
   TuplePrefixPrinter<TuplePolicy<Tuple>::tuple_size>::
       TersePrintPrefixToStrings(value, &result);
   return result;
 }
 #endif  // GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_
 
 }  // namespace internal
 
 #if GTEST_HAS_ABSL
 namespace internal2 {
 template <typename T>
 void TypeWithoutFormatter<T, kConvertibleToStringView>::PrintValue(
     const T& value, ::std::ostream* os) {
   internal::PrintTo(absl::string_view(value), os);
 }
 }  // namespace internal2
 #endif
 
 template <typename T>
 ::std::string PrintToString(const T& value) {
   ::std::stringstream ss;
   internal::UniversalTersePrinter<T>::Print(value, &ss);
   return ss.str();
 }
 
 }  // namespace testing
 
 // Include any custom printer added by the local installation.
 // We must include this header at the end to make sure it can use the
 // declarations from this file.
 #include "gtest/internal/custom/gtest-printers.h"
 
 #endif  // GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
diff --git a/googletest/test/gtest-printers_test.cc b/googletest/test/gtest-printers_test.cc
index a373851d..49b3bd46 100644
--- a/googletest/test/gtest-printers_test.cc
+++ b/googletest/test/gtest-printers_test.cc
@@ -1,1731 +1,1737 @@
 // Copyright 2007, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 //
 // Author: wan@google.com (Zhanyong Wan)
 
 // Google Test - The Google C++ Testing and Mocking Framework
 //
 // This file tests the universal value printer.
 
 #include "gtest/gtest-printers.h"
 
 #include <ctype.h>
 #include <limits.h>
 #include <string.h>
 #include <algorithm>
 #include <deque>
 #include <list>
 #include <map>
 #include <set>
 #include <sstream>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "gtest/gtest.h"
 
 #if GTEST_HAS_UNORDERED_MAP_
 # include <unordered_map>  // NOLINT
 #endif  // GTEST_HAS_UNORDERED_MAP_
 
 #if GTEST_HAS_UNORDERED_SET_
 # include <unordered_set>  // NOLINT
 #endif  // GTEST_HAS_UNORDERED_SET_
 
 #if GTEST_HAS_STD_FORWARD_LIST_
 # include <forward_list> // NOLINT
 #endif  // GTEST_HAS_STD_FORWARD_LIST_
 
 // Some user-defined types for testing the universal value printer.
 
 // An anonymous enum type.
 enum AnonymousEnum {
   kAE1 = -1,
   kAE2 = 1
 };
 
 // An enum without a user-defined printer.
 enum EnumWithoutPrinter {
   kEWP1 = -2,
   kEWP2 = 42
 };
 
 // An enum with a << operator.
 enum EnumWithStreaming {
   kEWS1 = 10
 };
 
 std::ostream& operator<<(std::ostream& os, EnumWithStreaming e) {
   return os << (e == kEWS1 ? "kEWS1" : "invalid");
 }
 
 // An enum with a PrintTo() function.
 enum EnumWithPrintTo {
   kEWPT1 = 1
 };
 
 void PrintTo(EnumWithPrintTo e, std::ostream* os) {
   *os << (e == kEWPT1 ? "kEWPT1" : "invalid");
 }
 
 // A class implicitly convertible to BiggestInt.
 class BiggestIntConvertible {
  public:
   operator ::testing::internal::BiggestInt() const { return 42; }
 };
 
 // A user-defined unprintable class template in the global namespace.
 template <typename T>
 class UnprintableTemplateInGlobal {
  public:
   UnprintableTemplateInGlobal() : value_() {}
  private:
   T value_;
 };
 
 // A user-defined streamable type in the global namespace.
 class StreamableInGlobal {
  public:
   virtual ~StreamableInGlobal() {}
 };
 
 inline void operator<<(::std::ostream& os, const StreamableInGlobal& /* x */) {
   os << "StreamableInGlobal";
 }
 
 void operator<<(::std::ostream& os, const StreamableInGlobal* /* x */) {
   os << "StreamableInGlobal*";
 }
 
 namespace foo {
 
 // A user-defined unprintable type in a user namespace.
 class UnprintableInFoo {
  public:
   UnprintableInFoo() : z_(0) { memcpy(xy_, "\xEF\x12\x0\x0\x34\xAB\x0\x0", 8); }
   double z() const { return z_; }
  private:
   char xy_[8];
   double z_;
 };
 
 // A user-defined printable type in a user-chosen namespace.
 struct PrintableViaPrintTo {
   PrintableViaPrintTo() : value() {}
   int value;
 };
 
 void PrintTo(const PrintableViaPrintTo& x, ::std::ostream* os) {
   *os << "PrintableViaPrintTo: " << x.value;
 }
 
 // A type with a user-defined << for printing its pointer.
 struct PointerPrintable {
 };
 
 ::std::ostream& operator<<(::std::ostream& os,
                            const PointerPrintable* /* x */) {
   return os << "PointerPrintable*";
 }
 
 // A user-defined printable class template in a user-chosen namespace.
 template <typename T>
 class PrintableViaPrintToTemplate {
  public:
   explicit PrintableViaPrintToTemplate(const T& a_value) : value_(a_value) {}
 
   const T& value() const { return value_; }
  private:
   T value_;
 };
 
 template <typename T>
 void PrintTo(const PrintableViaPrintToTemplate<T>& x, ::std::ostream* os) {
   *os << "PrintableViaPrintToTemplate: " << x.value();
 }
 
 // A user-defined streamable class template in a user namespace.
 template <typename T>
 class StreamableTemplateInFoo {
  public:
   StreamableTemplateInFoo() : value_() {}
 
   const T& value() const { return value_; }
  private:
   T value_;
 };
 
 template <typename T>
 inline ::std::ostream& operator<<(::std::ostream& os,
                                   const StreamableTemplateInFoo<T>& x) {
   return os << "StreamableTemplateInFoo: " << x.value();
 }
 
 // A user-defined streamable but recursivly-defined container type in
 // a user namespace, it mimics therefore std::filesystem::path or
 // boost::filesystem::path.
 class PathLike {
  public:
   struct iterator {
     typedef PathLike value_type;
   };
 
   PathLike() {}
 
   iterator begin() const { return iterator(); }
   iterator end() const { return iterator(); }
 
   friend ::std::ostream& operator<<(::std::ostream& os, const PathLike&) {
     return os << "Streamable-PathLike";
   }
 };
 
 }  // namespace foo
 
 namespace testing {
 namespace gtest_printers_test {
 
 using ::std::deque;
 using ::std::list;
 using ::std::make_pair;
 using ::std::map;
 using ::std::multimap;
 using ::std::multiset;
 using ::std::pair;
 using ::std::set;
 using ::std::vector;
 using ::testing::PrintToString;
 using ::testing::internal::FormatForComparisonFailureMessage;
 using ::testing::internal::ImplicitCast_;
 using ::testing::internal::NativeArray;
 using ::testing::internal::RE;
 using ::testing::internal::RelationToSourceReference;
 using ::testing::internal::Strings;
 using ::testing::internal::UniversalPrint;
 using ::testing::internal::UniversalPrinter;
 using ::testing::internal::UniversalTersePrint;
 #if GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_
 using ::testing::internal::UniversalTersePrintTupleFieldsToStrings;
 #endif
 
 // Prints a value to a string using the universal value printer.  This
 // is a helper for testing UniversalPrinter<T>::Print() for various types.
 template <typename T>
 std::string Print(const T& value) {
   ::std::stringstream ss;
   UniversalPrinter<T>::Print(value, &ss);
   return ss.str();
 }
 
 // Prints a value passed by reference to a string, using the universal
 // value printer.  This is a helper for testing
 // UniversalPrinter<T&>::Print() for various types.
 template <typename T>
 std::string PrintByRef(const T& value) {
   ::std::stringstream ss;
   UniversalPrinter<T&>::Print(value, &ss);
   return ss.str();
 }
 
 // Tests printing various enum types.
 
 TEST(PrintEnumTest, AnonymousEnum) {
   EXPECT_EQ("-1", Print(kAE1));
   EXPECT_EQ("1", Print(kAE2));
 }
 
 TEST(PrintEnumTest, EnumWithoutPrinter) {
   EXPECT_EQ("-2", Print(kEWP1));
   EXPECT_EQ("42", Print(kEWP2));
 }
 
 TEST(PrintEnumTest, EnumWithStreaming) {
   EXPECT_EQ("kEWS1", Print(kEWS1));
   EXPECT_EQ("invalid", Print(static_cast<EnumWithStreaming>(0)));
 }
 
 TEST(PrintEnumTest, EnumWithPrintTo) {
   EXPECT_EQ("kEWPT1", Print(kEWPT1));
   EXPECT_EQ("invalid", Print(static_cast<EnumWithPrintTo>(0)));
 }
 
 // Tests printing a class implicitly convertible to BiggestInt.
 
 TEST(PrintClassTest, BiggestIntConvertible) {
   EXPECT_EQ("42", Print(BiggestIntConvertible()));
 }
 
 // Tests printing various char types.
 
 // char.
 TEST(PrintCharTest, PlainChar) {
   EXPECT_EQ("'\\0'", Print('\0'));
   EXPECT_EQ("'\\'' (39, 0x27)", Print('\''));
   EXPECT_EQ("'\"' (34, 0x22)", Print('"'));
   EXPECT_EQ("'?' (63, 0x3F)", Print('?'));
   EXPECT_EQ("'\\\\' (92, 0x5C)", Print('\\'));
   EXPECT_EQ("'\\a' (7)", Print('\a'));
   EXPECT_EQ("'\\b' (8)", Print('\b'));
   EXPECT_EQ("'\\f' (12, 0xC)", Print('\f'));
   EXPECT_EQ("'\\n' (10, 0xA)", Print('\n'));
   EXPECT_EQ("'\\r' (13, 0xD)", Print('\r'));
   EXPECT_EQ("'\\t' (9)", Print('\t'));
   EXPECT_EQ("'\\v' (11, 0xB)", Print('\v'));
   EXPECT_EQ("'\\x7F' (127)", Print('\x7F'));
   EXPECT_EQ("'\\xFF' (255)", Print('\xFF'));
   EXPECT_EQ("' ' (32, 0x20)", Print(' '));
   EXPECT_EQ("'a' (97, 0x61)", Print('a'));
 }
 
 // signed char.
 TEST(PrintCharTest, SignedChar) {
   EXPECT_EQ("'\\0'", Print(static_cast<signed char>('\0')));
   EXPECT_EQ("'\\xCE' (-50)",
             Print(static_cast<signed char>(-50)));
 }
 
 // unsigned char.
 TEST(PrintCharTest, UnsignedChar) {
   EXPECT_EQ("'\\0'", Print(static_cast<unsigned char>('\0')));
   EXPECT_EQ("'b' (98, 0x62)",
             Print(static_cast<unsigned char>('b')));
 }
 
 // Tests printing other simple, built-in types.
 
 // bool.
 TEST(PrintBuiltInTypeTest, Bool) {
   EXPECT_EQ("false", Print(false));
   EXPECT_EQ("true", Print(true));
 }
 
 // wchar_t.
 TEST(PrintBuiltInTypeTest, Wchar_t) {
   EXPECT_EQ("L'\\0'", Print(L'\0'));
   EXPECT_EQ("L'\\'' (39, 0x27)", Print(L'\''));
   EXPECT_EQ("L'\"' (34, 0x22)", Print(L'"'));
   EXPECT_EQ("L'?' (63, 0x3F)", Print(L'?'));
   EXPECT_EQ("L'\\\\' (92, 0x5C)", Print(L'\\'));
   EXPECT_EQ("L'\\a' (7)", Print(L'\a'));
   EXPECT_EQ("L'\\b' (8)", Print(L'\b'));
   EXPECT_EQ("L'\\f' (12, 0xC)", Print(L'\f'));
   EXPECT_EQ("L'\\n' (10, 0xA)", Print(L'\n'));
   EXPECT_EQ("L'\\r' (13, 0xD)", Print(L'\r'));
   EXPECT_EQ("L'\\t' (9)", Print(L'\t'));
   EXPECT_EQ("L'\\v' (11, 0xB)", Print(L'\v'));
   EXPECT_EQ("L'\\x7F' (127)", Print(L'\x7F'));
   EXPECT_EQ("L'\\xFF' (255)", Print(L'\xFF'));
   EXPECT_EQ("L' ' (32, 0x20)", Print(L' '));
   EXPECT_EQ("L'a' (97, 0x61)", Print(L'a'));
   EXPECT_EQ("L'\\x576' (1398)", Print(static_cast<wchar_t>(0x576)));
   EXPECT_EQ("L'\\xC74D' (51021)", Print(static_cast<wchar_t>(0xC74D)));
 }
 
 // Test that Int64 provides more storage than wchar_t.
 TEST(PrintTypeSizeTest, Wchar_t) {
   EXPECT_LT(sizeof(wchar_t), sizeof(testing::internal::Int64));
 }
 
 // Various integer types.
 TEST(PrintBuiltInTypeTest, Integer) {
   EXPECT_EQ("'\\xFF' (255)", Print(static_cast<unsigned char>(255)));  // uint8
   EXPECT_EQ("'\\x80' (-128)", Print(static_cast<signed char>(-128)));  // int8
   EXPECT_EQ("65535", Print(USHRT_MAX));  // uint16
   EXPECT_EQ("-32768", Print(SHRT_MIN));  // int16
   EXPECT_EQ("4294967295", Print(UINT_MAX));  // uint32
   EXPECT_EQ("-2147483648", Print(INT_MIN));  // int32
   EXPECT_EQ("18446744073709551615",
             Print(static_cast<testing::internal::UInt64>(-1)));  // uint64
   EXPECT_EQ("-9223372036854775808",
             Print(static_cast<testing::internal::Int64>(1) << 63));  // int64
 }
 
 // Size types.
 TEST(PrintBuiltInTypeTest, Size_t) {
   EXPECT_EQ("1", Print(sizeof('a')));  // size_t.
 #if !GTEST_OS_WINDOWS
   // Windows has no ssize_t type.
   EXPECT_EQ("-2", Print(static_cast<ssize_t>(-2)));  // ssize_t.
 #endif  // !GTEST_OS_WINDOWS
 }
 
 // Floating-points.
 TEST(PrintBuiltInTypeTest, FloatingPoints) {
   EXPECT_EQ("1.5", Print(1.5f));   // float
   EXPECT_EQ("-2.5", Print(-2.5));  // double
 }
 
 // Since ::std::stringstream::operator<<(const void *) formats the pointer
 // output differently with different compilers, we have to create the expected
 // output first and use it as our expectation.
 static std::string PrintPointer(const void* p) {
   ::std::stringstream expected_result_stream;
   expected_result_stream << p;
   return expected_result_stream.str();
 }
 
 // Tests printing C strings.
 
 // const char*.
 TEST(PrintCStringTest, Const) {
   const char* p = "World";
   EXPECT_EQ(PrintPointer(p) + " pointing to \"World\"", Print(p));
 }
 
 // char*.
 TEST(PrintCStringTest, NonConst) {
   char p[] = "Hi";
   EXPECT_EQ(PrintPointer(p) + " pointing to \"Hi\"",
             Print(static_cast<char*>(p)));
 }
 
 // NULL C string.
 TEST(PrintCStringTest, Null) {
   const char* p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // Tests that C strings are escaped properly.
 TEST(PrintCStringTest, EscapesProperly) {
   const char* p = "'\"?\\\a\b\f\n\r\t\v\x7F\xFF a";
   EXPECT_EQ(PrintPointer(p) + " pointing to \"'\\\"?\\\\\\a\\b\\f"
             "\\n\\r\\t\\v\\x7F\\xFF a\"",
             Print(p));
 }
 
 // MSVC compiler can be configured to define whar_t as a typedef
 // of unsigned short. Defining an overload for const wchar_t* in that case
 // would cause pointers to unsigned shorts be printed as wide strings,
 // possibly accessing more memory than intended and causing invalid
 // memory accesses. MSVC defines _NATIVE_WCHAR_T_DEFINED symbol when
 // wchar_t is implemented as a native type.
 #if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
 
 // const wchar_t*.
 TEST(PrintWideCStringTest, Const) {
   const wchar_t* p = L"World";
   EXPECT_EQ(PrintPointer(p) + " pointing to L\"World\"", Print(p));
 }
 
 // wchar_t*.
 TEST(PrintWideCStringTest, NonConst) {
   wchar_t p[] = L"Hi";
   EXPECT_EQ(PrintPointer(p) + " pointing to L\"Hi\"",
             Print(static_cast<wchar_t*>(p)));
 }
 
 // NULL wide C string.
 TEST(PrintWideCStringTest, Null) {
   const wchar_t* p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // Tests that wide C strings are escaped properly.
 TEST(PrintWideCStringTest, EscapesProperly) {
   const wchar_t s[] = {'\'', '"', '?', '\\', '\a', '\b', '\f', '\n', '\r',
                        '\t', '\v', 0xD3, 0x576, 0x8D3, 0xC74D, ' ', 'a', '\0'};
   EXPECT_EQ(PrintPointer(s) + " pointing to L\"'\\\"?\\\\\\a\\b\\f"
             "\\n\\r\\t\\v\\xD3\\x576\\x8D3\\xC74D a\"",
             Print(static_cast<const wchar_t*>(s)));
 }
 #endif  // native wchar_t
 
 // Tests printing pointers to other char types.
 
 // signed char*.
 TEST(PrintCharPointerTest, SignedChar) {
   signed char* p = reinterpret_cast<signed char*>(0x1234);
   EXPECT_EQ(PrintPointer(p), Print(p));
   p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // const signed char*.
 TEST(PrintCharPointerTest, ConstSignedChar) {
   signed char* p = reinterpret_cast<signed char*>(0x1234);
   EXPECT_EQ(PrintPointer(p), Print(p));
   p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // unsigned char*.
 TEST(PrintCharPointerTest, UnsignedChar) {
   unsigned char* p = reinterpret_cast<unsigned char*>(0x1234);
   EXPECT_EQ(PrintPointer(p), Print(p));
   p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // const unsigned char*.
 TEST(PrintCharPointerTest, ConstUnsignedChar) {
   const unsigned char* p = reinterpret_cast<const unsigned char*>(0x1234);
   EXPECT_EQ(PrintPointer(p), Print(p));
   p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // Tests printing pointers to simple, built-in types.
 
 // bool*.
 TEST(PrintPointerToBuiltInTypeTest, Bool) {
   bool* p = reinterpret_cast<bool*>(0xABCD);
   EXPECT_EQ(PrintPointer(p), Print(p));
   p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // void*.
 TEST(PrintPointerToBuiltInTypeTest, Void) {
   void* p = reinterpret_cast<void*>(0xABCD);
   EXPECT_EQ(PrintPointer(p), Print(p));
   p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // const void*.
 TEST(PrintPointerToBuiltInTypeTest, ConstVoid) {
   const void* p = reinterpret_cast<const void*>(0xABCD);
   EXPECT_EQ(PrintPointer(p), Print(p));
   p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // Tests printing pointers to pointers.
 TEST(PrintPointerToPointerTest, IntPointerPointer) {
   int** p = reinterpret_cast<int**>(0xABCD);
   EXPECT_EQ(PrintPointer(p), Print(p));
   p = NULL;
   EXPECT_EQ("NULL", Print(p));
 }
 
 // Tests printing (non-member) function pointers.
 
 void MyFunction(int /* n */) {}
 
 TEST(PrintPointerTest, NonMemberFunctionPointer) {
   // We cannot directly cast &MyFunction to const void* because the
   // standard disallows casting between pointers to functions and
   // pointers to objects, and some compilers (e.g. GCC 3.4) enforce
   // this limitation.
   EXPECT_EQ(
       PrintPointer(reinterpret_cast<const void*>(
           reinterpret_cast<internal::BiggestInt>(&MyFunction))),
       Print(&MyFunction));
   int (*p)(bool) = NULL;  // NOLINT
   EXPECT_EQ("NULL", Print(p));
 }
 
 // An assertion predicate determining whether a one string is a prefix for
 // another.
 template <typename StringType>
 AssertionResult HasPrefix(const StringType& str, const StringType& prefix) {
   if (str.find(prefix, 0) == 0)
     return AssertionSuccess();
 
   const bool is_wide_string = sizeof(prefix[0]) > 1;
   const char* const begin_string_quote = is_wide_string ? "L\"" : "\"";
   return AssertionFailure()
       << begin_string_quote << prefix << "\" is not a prefix of "
       << begin_string_quote << str << "\"\n";
 }
 
 // Tests printing member variable pointers.  Although they are called
 // pointers, they don't point to a location in the address space.
 // Their representation is implementation-defined.  Thus they will be
 // printed as raw bytes.
 
 struct Foo {
  public:
   virtual ~Foo() {}
   int MyMethod(char x) { return x + 1; }
   virtual char MyVirtualMethod(int /* n */) { return 'a'; }
 
   int value;
 };
 
 TEST(PrintPointerTest, MemberVariablePointer) {
   EXPECT_TRUE(HasPrefix(Print(&Foo::value),
                         Print(sizeof(&Foo::value)) + "-byte object "));
   int (Foo::*p) = NULL;  // NOLINT
   EXPECT_TRUE(HasPrefix(Print(p),
                         Print(sizeof(p)) + "-byte object "));
 }
 
 // Tests printing member function pointers.  Although they are called
 // pointers, they don't point to a location in the address space.
 // Their representation is implementation-defined.  Thus they will be
 // printed as raw bytes.
 TEST(PrintPointerTest, MemberFunctionPointer) {
   EXPECT_TRUE(HasPrefix(Print(&Foo::MyMethod),
                         Print(sizeof(&Foo::MyMethod)) + "-byte object "));
   EXPECT_TRUE(
       HasPrefix(Print(&Foo::MyVirtualMethod),
                 Print(sizeof((&Foo::MyVirtualMethod))) + "-byte object "));
   int (Foo::*p)(char) = NULL;  // NOLINT
   EXPECT_TRUE(HasPrefix(Print(p),
                         Print(sizeof(p)) + "-byte object "));
 }
 
 // Tests printing C arrays.
 
 // The difference between this and Print() is that it ensures that the
 // argument is a reference to an array.
 template <typename T, size_t N>
 std::string PrintArrayHelper(T (&a)[N]) {
   return Print(a);
 }
 
 // One-dimensional array.
 TEST(PrintArrayTest, OneDimensionalArray) {
   int a[5] = { 1, 2, 3, 4, 5 };
   EXPECT_EQ("{ 1, 2, 3, 4, 5 }", PrintArrayHelper(a));
 }
 
 // Two-dimensional array.
 TEST(PrintArrayTest, TwoDimensionalArray) {
   int a[2][5] = {
     { 1, 2, 3, 4, 5 },
     { 6, 7, 8, 9, 0 }
   };
   EXPECT_EQ("{ { 1, 2, 3, 4, 5 }, { 6, 7, 8, 9, 0 } }", PrintArrayHelper(a));
 }
 
 // Array of const elements.
 TEST(PrintArrayTest, ConstArray) {
   const bool a[1] = { false };
   EXPECT_EQ("{ false }", PrintArrayHelper(a));
 }
 
 // char array without terminating NUL.
 TEST(PrintArrayTest, CharArrayWithNoTerminatingNul) {
   // Array a contains '\0' in the middle and doesn't end with '\0'.
   char a[] = { 'H', '\0', 'i' };
   EXPECT_EQ("\"H\\0i\" (no terminating NUL)", PrintArrayHelper(a));
 }
 
 // const char array with terminating NUL.
 TEST(PrintArrayTest, ConstCharArrayWithTerminatingNul) {
   const char a[] = "\0Hi";
   EXPECT_EQ("\"\\0Hi\"", PrintArrayHelper(a));
 }
 
 // const wchar_t array without terminating NUL.
 TEST(PrintArrayTest, WCharArrayWithNoTerminatingNul) {
   // Array a contains '\0' in the middle and doesn't end with '\0'.
   const wchar_t a[] = { L'H', L'\0', L'i' };
   EXPECT_EQ("L\"H\\0i\" (no terminating NUL)", PrintArrayHelper(a));
 }
 
 // wchar_t array with terminating NUL.
 TEST(PrintArrayTest, WConstCharArrayWithTerminatingNul) {
   const wchar_t a[] = L"\0Hi";
   EXPECT_EQ("L\"\\0Hi\"", PrintArrayHelper(a));
 }
 
 // Array of objects.
 TEST(PrintArrayTest, ObjectArray) {
   std::string a[3] = {"Hi", "Hello", "Ni hao"};
   EXPECT_EQ("{ \"Hi\", \"Hello\", \"Ni hao\" }", PrintArrayHelper(a));
 }
 
 // Array with many elements.
 TEST(PrintArrayTest, BigArray) {
   int a[100] = { 1, 2, 3 };
   EXPECT_EQ("{ 1, 2, 3, 0, 0, 0, 0, 0, ..., 0, 0, 0, 0, 0, 0, 0, 0 }",
             PrintArrayHelper(a));
 }
 
 // Tests printing ::string and ::std::string.
 
 #if GTEST_HAS_GLOBAL_STRING
 // ::string.
 TEST(PrintStringTest, StringInGlobalNamespace) {
   const char s[] = "'\"?\\\a\b\f\n\0\r\t\v\x7F\xFF a";
   const ::string str(s, sizeof(s));
   EXPECT_EQ("\"'\\\"?\\\\\\a\\b\\f\\n\\0\\r\\t\\v\\x7F\\xFF a\\0\"",
             Print(str));
 }
 #endif  // GTEST_HAS_GLOBAL_STRING
 
 // ::std::string.
 TEST(PrintStringTest, StringInStdNamespace) {
   const char s[] = "'\"?\\\a\b\f\n\0\r\t\v\x7F\xFF a";
   const ::std::string str(s, sizeof(s));
   EXPECT_EQ("\"'\\\"?\\\\\\a\\b\\f\\n\\0\\r\\t\\v\\x7F\\xFF a\\0\"",
             Print(str));
 }
 
 TEST(PrintStringTest, StringAmbiguousHex) {
   // "\x6BANANA" is ambiguous, it can be interpreted as starting with either of:
   // '\x6', '\x6B', or '\x6BA'.
 
   // a hex escaping sequence following by a decimal digit
   EXPECT_EQ("\"0\\x12\" \"3\"", Print(::std::string("0\x12" "3")));
   // a hex escaping sequence following by a hex digit (lower-case)
   EXPECT_EQ("\"mm\\x6\" \"bananas\"", Print(::std::string("mm\x6" "bananas")));
   // a hex escaping sequence following by a hex digit (upper-case)
   EXPECT_EQ("\"NOM\\x6\" \"BANANA\"", Print(::std::string("NOM\x6" "BANANA")));
   // a hex escaping sequence following by a non-xdigit
   EXPECT_EQ("\"!\\x5-!\"", Print(::std::string("!\x5-!")));
 }
 
 // Tests printing ::wstring and ::std::wstring.
 
 #if GTEST_HAS_GLOBAL_WSTRING
 // ::wstring.
 TEST(PrintWideStringTest, StringInGlobalNamespace) {
   const wchar_t s[] = L"'\"?\\\a\b\f\n\0\r\t\v\xD3\x576\x8D3\xC74D a";
   const ::wstring str(s, sizeof(s)/sizeof(wchar_t));
   EXPECT_EQ("L\"'\\\"?\\\\\\a\\b\\f\\n\\0\\r\\t\\v"
             "\\xD3\\x576\\x8D3\\xC74D a\\0\"",
             Print(str));
 }
 #endif  // GTEST_HAS_GLOBAL_WSTRING
 
 #if GTEST_HAS_STD_WSTRING
 // ::std::wstring.
 TEST(PrintWideStringTest, StringInStdNamespace) {
   const wchar_t s[] = L"'\"?\\\a\b\f\n\0\r\t\v\xD3\x576\x8D3\xC74D a";
   const ::std::wstring str(s, sizeof(s)/sizeof(wchar_t));
   EXPECT_EQ("L\"'\\\"?\\\\\\a\\b\\f\\n\\0\\r\\t\\v"
             "\\xD3\\x576\\x8D3\\xC74D a\\0\"",
             Print(str));
 }
 
 TEST(PrintWideStringTest, StringAmbiguousHex) {
   // same for wide strings.
   EXPECT_EQ("L\"0\\x12\" L\"3\"", Print(::std::wstring(L"0\x12" L"3")));
   EXPECT_EQ("L\"mm\\x6\" L\"bananas\"",
             Print(::std::wstring(L"mm\x6" L"bananas")));
   EXPECT_EQ("L\"NOM\\x6\" L\"BANANA\"",
             Print(::std::wstring(L"NOM\x6" L"BANANA")));
   EXPECT_EQ("L\"!\\x5-!\"", Print(::std::wstring(L"!\x5-!")));
 }
 #endif  // GTEST_HAS_STD_WSTRING
 
 // Tests printing types that support generic streaming (i.e. streaming
 // to std::basic_ostream<Char, CharTraits> for any valid Char and
 // CharTraits types).
 
 // Tests printing a non-template type that supports generic streaming.
 
 class AllowsGenericStreaming {};
 
 template <typename Char, typename CharTraits>
 std::basic_ostream<Char, CharTraits>& operator<<(
     std::basic_ostream<Char, CharTraits>& os,
     const AllowsGenericStreaming& /* a */) {
   return os << "AllowsGenericStreaming";
 }
 
 TEST(PrintTypeWithGenericStreamingTest, NonTemplateType) {
   AllowsGenericStreaming a;
   EXPECT_EQ("AllowsGenericStreaming", Print(a));
 }
 
 // Tests printing a template type that supports generic streaming.
 
 template <typename T>
 class AllowsGenericStreamingTemplate {};
 
 template <typename Char, typename CharTraits, typename T>
 std::basic_ostream<Char, CharTraits>& operator<<(
     std::basic_ostream<Char, CharTraits>& os,
     const AllowsGenericStreamingTemplate<T>& /* a */) {
   return os << "AllowsGenericStreamingTemplate";
 }
 
 TEST(PrintTypeWithGenericStreamingTest, TemplateType) {
   AllowsGenericStreamingTemplate<int> a;
   EXPECT_EQ("AllowsGenericStreamingTemplate", Print(a));
 }
 
 // Tests printing a type that supports generic streaming and can be
 // implicitly converted to another printable type.
 
 template <typename T>
 class AllowsGenericStreamingAndImplicitConversionTemplate {
  public:
   operator bool() const { return false; }
 };
 
 template <typename Char, typename CharTraits, typename T>
 std::basic_ostream<Char, CharTraits>& operator<<(
     std::basic_ostream<Char, CharTraits>& os,
     const AllowsGenericStreamingAndImplicitConversionTemplate<T>& /* a */) {
   return os << "AllowsGenericStreamingAndImplicitConversionTemplate";
 }
 
 TEST(PrintTypeWithGenericStreamingTest, TypeImplicitlyConvertible) {
   AllowsGenericStreamingAndImplicitConversionTemplate<int> a;
   EXPECT_EQ("AllowsGenericStreamingAndImplicitConversionTemplate", Print(a));
 }
 
 #if GTEST_HAS_ABSL
 
 // Tests printing ::absl::string_view.
 
 TEST(PrintStringViewTest, SimpleStringView) {
   const ::absl::string_view sp = "Hello";
   EXPECT_EQ("\"Hello\"", Print(sp));
 }
 
 TEST(PrintStringViewTest, UnprintableCharacters) {
   const char str[] = "NUL (\0) and \r\t";
   const ::absl::string_view sp(str, sizeof(str) - 1);
   EXPECT_EQ("\"NUL (\\0) and \\r\\t\"", Print(sp));
 }
 
 #endif  // GTEST_HAS_ABSL
 
 // Tests printing STL containers.
 
 TEST(PrintStlContainerTest, EmptyDeque) {
   deque<char> empty;
   EXPECT_EQ("{}", Print(empty));
 }
 
 TEST(PrintStlContainerTest, NonEmptyDeque) {
   deque<int> non_empty;
   non_empty.push_back(1);
   non_empty.push_back(3);
   EXPECT_EQ("{ 1, 3 }", Print(non_empty));
 }
 
 #if GTEST_HAS_UNORDERED_MAP_
 
 TEST(PrintStlContainerTest, OneElementHashMap) {
   ::std::unordered_map<int, char> map1;
   map1[1] = 'a';
   EXPECT_EQ("{ (1, 'a' (97, 0x61)) }", Print(map1));
 }
 
 TEST(PrintStlContainerTest, HashMultiMap) {
   ::std::unordered_multimap<int, bool> map1;
   map1.insert(make_pair(5, true));
   map1.insert(make_pair(5, false));
 
   // Elements of hash_multimap can be printed in any order.
   const std::string result = Print(map1);
   EXPECT_TRUE(result == "{ (5, true), (5, false) }" ||
               result == "{ (5, false), (5, true) }")
                   << " where Print(map1) returns \"" << result << "\".";
 }
 
 #endif  // GTEST_HAS_UNORDERED_MAP_
 
 #if GTEST_HAS_UNORDERED_SET_
 
 TEST(PrintStlContainerTest, HashSet) {
   ::std::unordered_set<int> set1;
   set1.insert(1);
   EXPECT_EQ("{ 1 }", Print(set1));
 }
 
 TEST(PrintStlContainerTest, HashMultiSet) {
   const int kSize = 5;
   int a[kSize] = { 1, 1, 2, 5, 1 };
   ::std::unordered_multiset<int> set1(a, a + kSize);
 
   // Elements of hash_multiset can be printed in any order.
   const std::string result = Print(set1);
   const std::string expected_pattern = "{ d, d, d, d, d }";  // d means a digit.
 
   // Verifies the result matches the expected pattern; also extracts
   // the numbers in the result.
   ASSERT_EQ(expected_pattern.length(), result.length());
   std::vector<int> numbers;
   for (size_t i = 0; i != result.length(); i++) {
     if (expected_pattern[i] == 'd') {
       ASSERT_NE(isdigit(static_cast<unsigned char>(result[i])), 0);
       numbers.push_back(result[i] - '0');
     } else {
       EXPECT_EQ(expected_pattern[i], result[i]) << " where result is "
                                                 << result;
     }
   }
 
   // Makes sure the result contains the right numbers.
   std::sort(numbers.begin(), numbers.end());
   std::sort(a, a + kSize);
   EXPECT_TRUE(std::equal(a, a + kSize, numbers.begin()));
 }
 
 #endif  //  GTEST_HAS_UNORDERED_SET_
 
 TEST(PrintStlContainerTest, List) {
   const std::string a[] = {"hello", "world"};
   const list<std::string> strings(a, a + 2);
   EXPECT_EQ("{ \"hello\", \"world\" }", Print(strings));
 }
 
 TEST(PrintStlContainerTest, Map) {
   map<int, bool> map1;
   map1[1] = true;
   map1[5] = false;
   map1[3] = true;
   EXPECT_EQ("{ (1, true), (3, true), (5, false) }", Print(map1));
 }
 
 TEST(PrintStlContainerTest, MultiMap) {
   multimap<bool, int> map1;
   // The make_pair template function would deduce the type as
   // pair<bool, int> here, and since the key part in a multimap has to
   // be constant, without a templated ctor in the pair class (as in
   // libCstd on Solaris), make_pair call would fail to compile as no
   // implicit conversion is found.  Thus explicit typename is used
   // here instead.
   map1.insert(pair<const bool, int>(true, 0));
   map1.insert(pair<const bool, int>(true, 1));
   map1.insert(pair<const bool, int>(false, 2));
   EXPECT_EQ("{ (false, 2), (true, 0), (true, 1) }", Print(map1));
 }
 
 TEST(PrintStlContainerTest, Set) {
   const unsigned int a[] = { 3, 0, 5 };
   set<unsigned int> set1(a, a + 3);
   EXPECT_EQ("{ 0, 3, 5 }", Print(set1));
 }
 
 TEST(PrintStlContainerTest, MultiSet) {
   const int a[] = { 1, 1, 2, 5, 1 };
   multiset<int> set1(a, a + 5);
   EXPECT_EQ("{ 1, 1, 1, 2, 5 }", Print(set1));
 }
 
 #if GTEST_HAS_STD_FORWARD_LIST_
 // <slist> is available on Linux in the google3 mode, but not on
 // Windows or Mac OS X.
 
 TEST(PrintStlContainerTest, SinglyLinkedList) {
   int a[] = { 9, 2, 8 };
   const std::forward_list<int> ints(a, a + 3);
   EXPECT_EQ("{ 9, 2, 8 }", Print(ints));
 }
 #endif  // GTEST_HAS_STD_FORWARD_LIST_
 
 TEST(PrintStlContainerTest, Pair) {
   pair<const bool, int> p(true, 5);
   EXPECT_EQ("(true, 5)", Print(p));
 }
 
 TEST(PrintStlContainerTest, Vector) {
   vector<int> v;
   v.push_back(1);
   v.push_back(2);
   EXPECT_EQ("{ 1, 2 }", Print(v));
 }
 
 TEST(PrintStlContainerTest, LongSequence) {
   const int a[100] = { 1, 2, 3 };
   const vector<int> v(a, a + 100);
   EXPECT_EQ("{ 1, 2, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, "
             "0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... }", Print(v));
 }
 
 TEST(PrintStlContainerTest, NestedContainer) {
   const int a1[] = { 1, 2 };
   const int a2[] = { 3, 4, 5 };
   const list<int> l1(a1, a1 + 2);
   const list<int> l2(a2, a2 + 3);
 
   vector<list<int> > v;
   v.push_back(l1);
   v.push_back(l2);
   EXPECT_EQ("{ { 1, 2 }, { 3, 4, 5 } }", Print(v));
 }
 
 TEST(PrintStlContainerTest, OneDimensionalNativeArray) {
   const int a[3] = { 1, 2, 3 };
   NativeArray<int> b(a, 3, RelationToSourceReference());
   EXPECT_EQ("{ 1, 2, 3 }", Print(b));
 }
 
 TEST(PrintStlContainerTest, TwoDimensionalNativeArray) {
   const int a[2][3] = { { 1, 2, 3 }, { 4, 5, 6 } };
   NativeArray<int[3]> b(a, 2, RelationToSourceReference());
   EXPECT_EQ("{ { 1, 2, 3 }, { 4, 5, 6 } }", Print(b));
 }
 
 // Tests that a class named iterator isn't treated as a container.
 
 struct iterator {
   char x;
 };
 
 TEST(PrintStlContainerTest, Iterator) {
   iterator it = {};
   EXPECT_EQ("1-byte object <00>", Print(it));
 }
 
 // Tests that a class named const_iterator isn't treated as a container.
 
 struct const_iterator {
   char x;
 };
 
 TEST(PrintStlContainerTest, ConstIterator) {
   const_iterator it = {};
   EXPECT_EQ("1-byte object <00>", Print(it));
 }
 
 #if GTEST_HAS_TR1_TUPLE
 // Tests printing ::std::tr1::tuples.
 
 // Tuples of various arities.
 TEST(PrintTr1TupleTest, VariousSizes) {
   ::std::tr1::tuple<> t0;
   EXPECT_EQ("()", Print(t0));
 
   ::std::tr1::tuple<int> t1(5);
   EXPECT_EQ("(5)", Print(t1));
 
   ::std::tr1::tuple<char, bool> t2('a', true);
   EXPECT_EQ("('a' (97, 0x61), true)", Print(t2));
 
   ::std::tr1::tuple<bool, int, int> t3(false, 2, 3);
   EXPECT_EQ("(false, 2, 3)", Print(t3));
 
   ::std::tr1::tuple<bool, int, int, int> t4(false, 2, 3, 4);
   EXPECT_EQ("(false, 2, 3, 4)", Print(t4));
 
   ::std::tr1::tuple<bool, int, int, int, bool> t5(false, 2, 3, 4, true);
   EXPECT_EQ("(false, 2, 3, 4, true)", Print(t5));
 
   ::std::tr1::tuple<bool, int, int, int, bool, int> t6(false, 2, 3, 4, true, 6);
   EXPECT_EQ("(false, 2, 3, 4, true, 6)", Print(t6));
 
   ::std::tr1::tuple<bool, int, int, int, bool, int, int> t7(
       false, 2, 3, 4, true, 6, 7);
   EXPECT_EQ("(false, 2, 3, 4, true, 6, 7)", Print(t7));
 
   ::std::tr1::tuple<bool, int, int, int, bool, int, int, bool> t8(
       false, 2, 3, 4, true, 6, 7, true);
   EXPECT_EQ("(false, 2, 3, 4, true, 6, 7, true)", Print(t8));
 
   ::std::tr1::tuple<bool, int, int, int, bool, int, int, bool, int> t9(
       false, 2, 3, 4, true, 6, 7, true, 9);
   EXPECT_EQ("(false, 2, 3, 4, true, 6, 7, true, 9)", Print(t9));
 
   const char* const str = "8";
   // VC++ 2010's implementation of tuple of C++0x is deficient, requiring
   // an explicit type cast of NULL to be used.
   ::std::tr1::tuple<bool, char, short, testing::internal::Int32,  // NOLINT
                     testing::internal::Int64, float, double, const char*, void*,
                     std::string>
       t10(false, 'a', static_cast<short>(3), 4, 5, 1.5F, -2.5, str,  // NOLINT
           ImplicitCast_<void*>(NULL), "10");
   EXPECT_EQ("(false, 'a' (97, 0x61), 3, 4, 5, 1.5, -2.5, " + PrintPointer(str) +
             " pointing to \"8\", NULL, \"10\")",
             Print(t10));
 }
 
 // Nested tuples.
 TEST(PrintTr1TupleTest, NestedTuple) {
   ::std::tr1::tuple< ::std::tr1::tuple<int, bool>, char> nested(
       ::std::tr1::make_tuple(5, true), 'a');
   EXPECT_EQ("((5, true), 'a' (97, 0x61))", Print(nested));
 }
 
 #endif  // GTEST_HAS_TR1_TUPLE
 
 #if GTEST_HAS_STD_TUPLE_
 // Tests printing ::std::tuples.
 
 // Tuples of various arities.
 TEST(PrintStdTupleTest, VariousSizes) {
   ::std::tuple<> t0;
   EXPECT_EQ("()", Print(t0));
 
   ::std::tuple<int> t1(5);
   EXPECT_EQ("(5)", Print(t1));
 
   ::std::tuple<char, bool> t2('a', true);
   EXPECT_EQ("('a' (97, 0x61), true)", Print(t2));
 
   ::std::tuple<bool, int, int> t3(false, 2, 3);
   EXPECT_EQ("(false, 2, 3)", Print(t3));
 
   ::std::tuple<bool, int, int, int> t4(false, 2, 3, 4);
   EXPECT_EQ("(false, 2, 3, 4)", Print(t4));
 
   ::std::tuple<bool, int, int, int, bool> t5(false, 2, 3, 4, true);
   EXPECT_EQ("(false, 2, 3, 4, true)", Print(t5));
 
   ::std::tuple<bool, int, int, int, bool, int> t6(false, 2, 3, 4, true, 6);
   EXPECT_EQ("(false, 2, 3, 4, true, 6)", Print(t6));
 
   ::std::tuple<bool, int, int, int, bool, int, int> t7(
       false, 2, 3, 4, true, 6, 7);
   EXPECT_EQ("(false, 2, 3, 4, true, 6, 7)", Print(t7));
 
   ::std::tuple<bool, int, int, int, bool, int, int, bool> t8(
       false, 2, 3, 4, true, 6, 7, true);
   EXPECT_EQ("(false, 2, 3, 4, true, 6, 7, true)", Print(t8));
 
   ::std::tuple<bool, int, int, int, bool, int, int, bool, int> t9(
       false, 2, 3, 4, true, 6, 7, true, 9);
   EXPECT_EQ("(false, 2, 3, 4, true, 6, 7, true, 9)", Print(t9));
 
   const char* const str = "8";
   // VC++ 2010's implementation of tuple of C++0x is deficient, requiring
   // an explicit type cast of NULL to be used.
   ::std::tuple<bool, char, short, testing::internal::Int32,  // NOLINT
                testing::internal::Int64, float, double, const char*, void*,
                std::string>
       t10(false, 'a', static_cast<short>(3), 4, 5, 1.5F, -2.5, str,  // NOLINT
           ImplicitCast_<void*>(NULL), "10");
   EXPECT_EQ("(false, 'a' (97, 0x61), 3, 4, 5, 1.5, -2.5, " + PrintPointer(str) +
             " pointing to \"8\", NULL, \"10\")",
             Print(t10));
 }
 
 // Nested tuples.
 TEST(PrintStdTupleTest, NestedTuple) {
   ::std::tuple< ::std::tuple<int, bool>, char> nested(
       ::std::make_tuple(5, true), 'a');
   EXPECT_EQ("((5, true), 'a' (97, 0x61))", Print(nested));
 }
 
 #endif  // GTEST_LANG_CXX11
 
+#if GTEST_LANG_CXX11
+TEST(PrintNullptrT, Basic) {
+  EXPECT_EQ("(nullptr)", Print(nullptr));
+}
+#endif  // GTEST_LANG_CXX11
+
 // Tests printing user-defined unprintable types.
 
 // Unprintable types in the global namespace.
 TEST(PrintUnprintableTypeTest, InGlobalNamespace) {
   EXPECT_EQ("1-byte object <00>",
             Print(UnprintableTemplateInGlobal<char>()));
 }
 
 // Unprintable types in a user namespace.
 TEST(PrintUnprintableTypeTest, InUserNamespace) {
   EXPECT_EQ("16-byte object <EF-12 00-00 34-AB 00-00 00-00 00-00 00-00 00-00>",
             Print(::foo::UnprintableInFoo()));
 }
 
 // Unprintable types are that too big to be printed completely.
 
 struct Big {
   Big() { memset(array, 0, sizeof(array)); }
   char array[257];
 };
 
 TEST(PrintUnpritableTypeTest, BigObject) {
   EXPECT_EQ("257-byte object <00-00 00-00 00-00 00-00 00-00 00-00 "
             "00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 "
             "00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 "
             "00-00 00-00 00-00 00-00 00-00 00-00 ... 00-00 00-00 00-00 "
             "00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 "
             "00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 "
             "00-00 00-00 00-00 00-00 00-00 00-00 00-00 00-00 00>",
             Print(Big()));
 }
 
 // Tests printing user-defined streamable types.
 
 // Streamable types in the global namespace.
 TEST(PrintStreamableTypeTest, InGlobalNamespace) {
   StreamableInGlobal x;
   EXPECT_EQ("StreamableInGlobal", Print(x));
   EXPECT_EQ("StreamableInGlobal*", Print(&x));
 }
 
 // Printable template types in a user namespace.
 TEST(PrintStreamableTypeTest, TemplateTypeInUserNamespace) {
   EXPECT_EQ("StreamableTemplateInFoo: 0",
             Print(::foo::StreamableTemplateInFoo<int>()));
 }
 
 // Tests printing a user-defined recursive container type that has a <<
 // operator.
 TEST(PrintStreamableTypeTest, PathLikeInUserNamespace) {
   ::foo::PathLike x;
   EXPECT_EQ("Streamable-PathLike", Print(x));
   const ::foo::PathLike cx;
   EXPECT_EQ("Streamable-PathLike", Print(cx));
 }
 
 // Tests printing user-defined types that have a PrintTo() function.
 TEST(PrintPrintableTypeTest, InUserNamespace) {
   EXPECT_EQ("PrintableViaPrintTo: 0",
             Print(::foo::PrintableViaPrintTo()));
 }
 
 // Tests printing a pointer to a user-defined type that has a <<
 // operator for its pointer.
 TEST(PrintPrintableTypeTest, PointerInUserNamespace) {
   ::foo::PointerPrintable x;
   EXPECT_EQ("PointerPrintable*", Print(&x));
 }
 
 // Tests printing user-defined class template that have a PrintTo() function.
 TEST(PrintPrintableTypeTest, TemplateInUserNamespace) {
   EXPECT_EQ("PrintableViaPrintToTemplate: 5",
             Print(::foo::PrintableViaPrintToTemplate<int>(5)));
 }
 
 // Tests that the universal printer prints both the address and the
 // value of a reference.
 TEST(PrintReferenceTest, PrintsAddressAndValue) {
   int n = 5;
   EXPECT_EQ("@" + PrintPointer(&n) + " 5", PrintByRef(n));
 
   int a[2][3] = {
     { 0, 1, 2 },
     { 3, 4, 5 }
   };
   EXPECT_EQ("@" + PrintPointer(a) + " { { 0, 1, 2 }, { 3, 4, 5 } }",
             PrintByRef(a));
 
   const ::foo::UnprintableInFoo x;
   EXPECT_EQ("@" + PrintPointer(&x) + " 16-byte object "
             "<EF-12 00-00 34-AB 00-00 00-00 00-00 00-00 00-00>",
             PrintByRef(x));
 }
 
 // Tests that the universal printer prints a function pointer passed by
 // reference.
 TEST(PrintReferenceTest, HandlesFunctionPointer) {
   void (*fp)(int n) = &MyFunction;
   const std::string fp_pointer_string =
       PrintPointer(reinterpret_cast<const void*>(&fp));
   // We cannot directly cast &MyFunction to const void* because the
   // standard disallows casting between pointers to functions and
   // pointers to objects, and some compilers (e.g. GCC 3.4) enforce
   // this limitation.
   const std::string fp_string = PrintPointer(reinterpret_cast<const void*>(
       reinterpret_cast<internal::BiggestInt>(fp)));
   EXPECT_EQ("@" + fp_pointer_string + " " + fp_string,
             PrintByRef(fp));
 }
 
 // Tests that the universal printer prints a member function pointer
 // passed by reference.
 TEST(PrintReferenceTest, HandlesMemberFunctionPointer) {
   int (Foo::*p)(char ch) = &Foo::MyMethod;
   EXPECT_TRUE(HasPrefix(
       PrintByRef(p),
       "@" + PrintPointer(reinterpret_cast<const void*>(&p)) + " " +
           Print(sizeof(p)) + "-byte object "));
 
   char (Foo::*p2)(int n) = &Foo::MyVirtualMethod;
   EXPECT_TRUE(HasPrefix(
       PrintByRef(p2),
       "@" + PrintPointer(reinterpret_cast<const void*>(&p2)) + " " +
           Print(sizeof(p2)) + "-byte object "));
 }
 
 // Tests that the universal printer prints a member variable pointer
 // passed by reference.
 TEST(PrintReferenceTest, HandlesMemberVariablePointer) {
   int (Foo::*p) = &Foo::value;  // NOLINT
   EXPECT_TRUE(HasPrefix(
       PrintByRef(p),
       "@" + PrintPointer(&p) + " " + Print(sizeof(p)) + "-byte object "));
 }
 
 // Tests that FormatForComparisonFailureMessage(), which is used to print
 // an operand in a comparison assertion (e.g. ASSERT_EQ) when the assertion
 // fails, formats the operand in the desired way.
 
 // scalar
 TEST(FormatForComparisonFailureMessageTest, WorksForScalar) {
   EXPECT_STREQ("123",
                FormatForComparisonFailureMessage(123, 124).c_str());
 }
 
 // non-char pointer
 TEST(FormatForComparisonFailureMessageTest, WorksForNonCharPointer) {
   int n = 0;
   EXPECT_EQ(PrintPointer(&n),
             FormatForComparisonFailureMessage(&n, &n).c_str());
 }
 
 // non-char array
 TEST(FormatForComparisonFailureMessageTest, FormatsNonCharArrayAsPointer) {
   // In expression 'array == x', 'array' is compared by pointer.
   // Therefore we want to print an array operand as a pointer.
   int n[] = { 1, 2, 3 };
   EXPECT_EQ(PrintPointer(n),
             FormatForComparisonFailureMessage(n, n).c_str());
 }
 
 // Tests formatting a char pointer when it's compared with another pointer.
 // In this case we want to print it as a raw pointer, as the comparison is by
 // pointer.
 
 // char pointer vs pointer
 TEST(FormatForComparisonFailureMessageTest, WorksForCharPointerVsPointer) {
   // In expression 'p == x', where 'p' and 'x' are (const or not) char
   // pointers, the operands are compared by pointer.  Therefore we
   // want to print 'p' as a pointer instead of a C string (we don't
   // even know if it's supposed to point to a valid C string).
 
   // const char*
   const char* s = "hello";
   EXPECT_EQ(PrintPointer(s),
             FormatForComparisonFailureMessage(s, s).c_str());
 
   // char*
   char ch = 'a';
   EXPECT_EQ(PrintPointer(&ch),
             FormatForComparisonFailureMessage(&ch, &ch).c_str());
 }
 
 // wchar_t pointer vs pointer
 TEST(FormatForComparisonFailureMessageTest, WorksForWCharPointerVsPointer) {
   // In expression 'p == x', where 'p' and 'x' are (const or not) char
   // pointers, the operands are compared by pointer.  Therefore we
   // want to print 'p' as a pointer instead of a wide C string (we don't
   // even know if it's supposed to point to a valid wide C string).
 
   // const wchar_t*
   const wchar_t* s = L"hello";
   EXPECT_EQ(PrintPointer(s),
             FormatForComparisonFailureMessage(s, s).c_str());
 
   // wchar_t*
   wchar_t ch = L'a';
   EXPECT_EQ(PrintPointer(&ch),
             FormatForComparisonFailureMessage(&ch, &ch).c_str());
 }
 
 // Tests formatting a char pointer when it's compared to a string object.
 // In this case we want to print the char pointer as a C string.
 
 #if GTEST_HAS_GLOBAL_STRING
 // char pointer vs ::string
 TEST(FormatForComparisonFailureMessageTest, WorksForCharPointerVsString) {
   const char* s = "hello \"world";
   EXPECT_STREQ("\"hello \\\"world\"",  // The string content should be escaped.
                FormatForComparisonFailureMessage(s, ::string()).c_str());
 
   // char*
   char str[] = "hi\1";
   char* p = str;
   EXPECT_STREQ("\"hi\\x1\"",  // The string content should be escaped.
                FormatForComparisonFailureMessage(p, ::string()).c_str());
 }
 #endif
 
 // char pointer vs std::string
 TEST(FormatForComparisonFailureMessageTest, WorksForCharPointerVsStdString) {
   const char* s = "hello \"world";
   EXPECT_STREQ("\"hello \\\"world\"",  // The string content should be escaped.
                FormatForComparisonFailureMessage(s, ::std::string()).c_str());
 
   // char*
   char str[] = "hi\1";
   char* p = str;
   EXPECT_STREQ("\"hi\\x1\"",  // The string content should be escaped.
                FormatForComparisonFailureMessage(p, ::std::string()).c_str());
 }
 
 #if GTEST_HAS_GLOBAL_WSTRING
 // wchar_t pointer vs ::wstring
 TEST(FormatForComparisonFailureMessageTest, WorksForWCharPointerVsWString) {
   const wchar_t* s = L"hi \"world";
   EXPECT_STREQ("L\"hi \\\"world\"",  // The string content should be escaped.
                FormatForComparisonFailureMessage(s, ::wstring()).c_str());
 
   // wchar_t*
   wchar_t str[] = L"hi\1";
   wchar_t* p = str;
   EXPECT_STREQ("L\"hi\\x1\"",  // The string content should be escaped.
                FormatForComparisonFailureMessage(p, ::wstring()).c_str());
 }
 #endif
 
 #if GTEST_HAS_STD_WSTRING
 // wchar_t pointer vs std::wstring
 TEST(FormatForComparisonFailureMessageTest, WorksForWCharPointerVsStdWString) {
   const wchar_t* s = L"hi \"world";
   EXPECT_STREQ("L\"hi \\\"world\"",  // The string content should be escaped.
                FormatForComparisonFailureMessage(s, ::std::wstring()).c_str());
 
   // wchar_t*
   wchar_t str[] = L"hi\1";
   wchar_t* p = str;
   EXPECT_STREQ("L\"hi\\x1\"",  // The string content should be escaped.
                FormatForComparisonFailureMessage(p, ::std::wstring()).c_str());
 }
 #endif
 
 // Tests formatting a char array when it's compared with a pointer or array.
 // In this case we want to print the array as a row pointer, as the comparison
 // is by pointer.
 
 // char array vs pointer
 TEST(FormatForComparisonFailureMessageTest, WorksForCharArrayVsPointer) {
   char str[] = "hi \"world\"";
   char* p = NULL;
   EXPECT_EQ(PrintPointer(str),
             FormatForComparisonFailureMessage(str, p).c_str());
 }
 
 // char array vs char array
 TEST(FormatForComparisonFailureMessageTest, WorksForCharArrayVsCharArray) {
   const char str[] = "hi \"world\"";
   EXPECT_EQ(PrintPointer(str),
             FormatForComparisonFailureMessage(str, str).c_str());
 }
 
 // wchar_t array vs pointer
 TEST(FormatForComparisonFailureMessageTest, WorksForWCharArrayVsPointer) {
   wchar_t str[] = L"hi \"world\"";
   wchar_t* p = NULL;
   EXPECT_EQ(PrintPointer(str),
             FormatForComparisonFailureMessage(str, p).c_str());
 }
 
 // wchar_t array vs wchar_t array
 TEST(FormatForComparisonFailureMessageTest, WorksForWCharArrayVsWCharArray) {
   const wchar_t str[] = L"hi \"world\"";
   EXPECT_EQ(PrintPointer(str),
             FormatForComparisonFailureMessage(str, str).c_str());
 }
 
 // Tests formatting a char array when it's compared with a string object.
 // In this case we want to print the array as a C string.
 
 #if GTEST_HAS_GLOBAL_STRING
 // char array vs string
 TEST(FormatForComparisonFailureMessageTest, WorksForCharArrayVsString) {
   const char str[] = "hi \"w\0rld\"";
   EXPECT_STREQ("\"hi \\\"w\"",  // The content should be escaped.
                                 // Embedded NUL terminates the string.
                FormatForComparisonFailureMessage(str, ::string()).c_str());
 }
 #endif
 
 // char array vs std::string
 TEST(FormatForComparisonFailureMessageTest, WorksForCharArrayVsStdString) {
   const char str[] = "hi \"world\"";
   EXPECT_STREQ("\"hi \\\"world\\\"\"",  // The content should be escaped.
                FormatForComparisonFailureMessage(str, ::std::string()).c_str());
 }
 
 #if GTEST_HAS_GLOBAL_WSTRING
 // wchar_t array vs wstring
 TEST(FormatForComparisonFailureMessageTest, WorksForWCharArrayVsWString) {
   const wchar_t str[] = L"hi \"world\"";
   EXPECT_STREQ("L\"hi \\\"world\\\"\"",  // The content should be escaped.
                FormatForComparisonFailureMessage(str, ::wstring()).c_str());
 }
 #endif
 
 #if GTEST_HAS_STD_WSTRING
 // wchar_t array vs std::wstring
 TEST(FormatForComparisonFailureMessageTest, WorksForWCharArrayVsStdWString) {
   const wchar_t str[] = L"hi \"w\0rld\"";
   EXPECT_STREQ(
       "L\"hi \\\"w\"",  // The content should be escaped.
                         // Embedded NUL terminates the string.
       FormatForComparisonFailureMessage(str, ::std::wstring()).c_str());
 }
 #endif
 
 // Useful for testing PrintToString().  We cannot use EXPECT_EQ()
 // there as its implementation uses PrintToString().  The caller must
 // ensure that 'value' has no side effect.
 #define EXPECT_PRINT_TO_STRING_(value, expected_string)         \
   EXPECT_TRUE(PrintToString(value) == (expected_string))        \
       << " where " #value " prints as " << (PrintToString(value))
 
 TEST(PrintToStringTest, WorksForScalar) {
   EXPECT_PRINT_TO_STRING_(123, "123");
 }
 
 TEST(PrintToStringTest, WorksForPointerToConstChar) {
   const char* p = "hello";
   EXPECT_PRINT_TO_STRING_(p, "\"hello\"");
 }
 
 TEST(PrintToStringTest, WorksForPointerToNonConstChar) {
   char s[] = "hello";
   char* p = s;
   EXPECT_PRINT_TO_STRING_(p, "\"hello\"");
 }
 
 TEST(PrintToStringTest, EscapesForPointerToConstChar) {
   const char* p = "hello\n";
   EXPECT_PRINT_TO_STRING_(p, "\"hello\\n\"");
 }
 
 TEST(PrintToStringTest, EscapesForPointerToNonConstChar) {
   char s[] = "hello\1";
   char* p = s;
   EXPECT_PRINT_TO_STRING_(p, "\"hello\\x1\"");
 }
 
 TEST(PrintToStringTest, WorksForArray) {
   int n[3] = { 1, 2, 3 };
   EXPECT_PRINT_TO_STRING_(n, "{ 1, 2, 3 }");
 }
 
 TEST(PrintToStringTest, WorksForCharArray) {
   char s[] = "hello";
   EXPECT_PRINT_TO_STRING_(s, "\"hello\"");
 }
 
 TEST(PrintToStringTest, WorksForCharArrayWithEmbeddedNul) {
   const char str_with_nul[] = "hello\0 world";
   EXPECT_PRINT_TO_STRING_(str_with_nul, "\"hello\\0 world\"");
 
   char mutable_str_with_nul[] = "hello\0 world";
   EXPECT_PRINT_TO_STRING_(mutable_str_with_nul, "\"hello\\0 world\"");
 }
 
   TEST(PrintToStringTest, ContainsNonLatin) {
   // Sanity test with valid UTF-8. Prints both in hex and as text.
   std::string non_ascii_str = ::std::string("오전 4:30");
   EXPECT_PRINT_TO_STRING_(non_ascii_str,
                           "\"\\xEC\\x98\\xA4\\xEC\\xA0\\x84 4:30\"\n"
                           "    As Text: \"오전 4:30\"");
   non_ascii_str = ::std::string("From ä — ẑ");
   EXPECT_PRINT_TO_STRING_(non_ascii_str,
                           "\"From \\xC3\\xA4 \\xE2\\x80\\x94 \\xE1\\xBA\\x91\""
                           "\n    As Text: \"From ä — ẑ\"");
 }
 
 TEST(IsValidUTF8Test, IllFormedUTF8) {
   // The following test strings are ill-formed UTF-8 and are printed
   // as hex only (or ASCII, in case of ASCII bytes) because IsValidUTF8() is
   // expected to fail, thus output does not contain "As Text:".
 
   static const char *const kTestdata[][2] = {
     // 2-byte lead byte followed by a single-byte character.
     {"\xC3\x74", "\"\\xC3t\""},
     // Valid 2-byte character followed by an orphan trail byte.
     {"\xC3\x84\xA4", "\"\\xC3\\x84\\xA4\""},
     // Lead byte without trail byte.
     {"abc\xC3", "\"abc\\xC3\""},
     // 3-byte lead byte, single-byte character, orphan trail byte.
     {"x\xE2\x70\x94", "\"x\\xE2p\\x94\""},
     // Truncated 3-byte character.
     {"\xE2\x80", "\"\\xE2\\x80\""},
     // Truncated 3-byte character followed by valid 2-byte char.
     {"\xE2\x80\xC3\x84", "\"\\xE2\\x80\\xC3\\x84\""},
     // Truncated 3-byte character followed by a single-byte character.
     {"\xE2\x80\x7A", "\"\\xE2\\x80z\""},
     // 3-byte lead byte followed by valid 3-byte character.
     {"\xE2\xE2\x80\x94", "\"\\xE2\\xE2\\x80\\x94\""},
     // 4-byte lead byte followed by valid 3-byte character.
     {"\xF0\xE2\x80\x94", "\"\\xF0\\xE2\\x80\\x94\""},
     // Truncated 4-byte character.
     {"\xF0\xE2\x80", "\"\\xF0\\xE2\\x80\""},
      // Invalid UTF-8 byte sequences embedded in other chars.
     {"abc\xE2\x80\x94\xC3\x74xyc", "\"abc\\xE2\\x80\\x94\\xC3txyc\""},
     {"abc\xC3\x84\xE2\x80\xC3\x84xyz",
      "\"abc\\xC3\\x84\\xE2\\x80\\xC3\\x84xyz\""},
     // Non-shortest UTF-8 byte sequences are also ill-formed.
     // The classics: xC0, xC1 lead byte.
     {"\xC0\x80", "\"\\xC0\\x80\""},
     {"\xC1\x81", "\"\\xC1\\x81\""},
     // Non-shortest sequences.
     {"\xE0\x80\x80", "\"\\xE0\\x80\\x80\""},
     {"\xf0\x80\x80\x80", "\"\\xF0\\x80\\x80\\x80\""},
     // Last valid code point before surrogate range, should be printed as text,
     // too.
     {"\xED\x9F\xBF", "\"\\xED\\x9F\\xBF\"\n    As Text: \"퟿\""},
     // Start of surrogate lead. Surrogates are not printed as text.
     {"\xED\xA0\x80", "\"\\xED\\xA0\\x80\""},
     // Last non-private surrogate lead.
     {"\xED\xAD\xBF", "\"\\xED\\xAD\\xBF\""},
     // First private-use surrogate lead.
     {"\xED\xAE\x80", "\"\\xED\\xAE\\x80\""},
     // Last private-use surrogate lead.
     {"\xED\xAF\xBF", "\"\\xED\\xAF\\xBF\""},
     // Mid-point of surrogate trail.
     {"\xED\xB3\xBF", "\"\\xED\\xB3\\xBF\""},
     // First valid code point after surrogate range, should be printed as text,
     // too.
     {"\xEE\x80\x80", "\"\\xEE\\x80\\x80\"\n    As Text: \"\""}
   };
 
   for (int i = 0; i < int(sizeof(kTestdata)/sizeof(kTestdata[0])); ++i) {
     EXPECT_PRINT_TO_STRING_(kTestdata[i][0], kTestdata[i][1]);
   }
 }
 
 #undef EXPECT_PRINT_TO_STRING_
 
 TEST(UniversalTersePrintTest, WorksForNonReference) {
   ::std::stringstream ss;
   UniversalTersePrint(123, &ss);
   EXPECT_EQ("123", ss.str());
 }
 
 TEST(UniversalTersePrintTest, WorksForReference) {
   const int& n = 123;
   ::std::stringstream ss;
   UniversalTersePrint(n, &ss);
   EXPECT_EQ("123", ss.str());
 }
 
 TEST(UniversalTersePrintTest, WorksForCString) {
   const char* s1 = "abc";
   ::std::stringstream ss1;
   UniversalTersePrint(s1, &ss1);
   EXPECT_EQ("\"abc\"", ss1.str());
 
   char* s2 = const_cast<char*>(s1);
   ::std::stringstream ss2;
   UniversalTersePrint(s2, &ss2);
   EXPECT_EQ("\"abc\"", ss2.str());
 
   const char* s3 = NULL;
   ::std::stringstream ss3;
   UniversalTersePrint(s3, &ss3);
   EXPECT_EQ("NULL", ss3.str());
 }
 
 TEST(UniversalPrintTest, WorksForNonReference) {
   ::std::stringstream ss;
   UniversalPrint(123, &ss);
   EXPECT_EQ("123", ss.str());
 }
 
 TEST(UniversalPrintTest, WorksForReference) {
   const int& n = 123;
   ::std::stringstream ss;
   UniversalPrint(n, &ss);
   EXPECT_EQ("123", ss.str());
 }
 
 TEST(UniversalPrintTest, WorksForCString) {
   const char* s1 = "abc";
   ::std::stringstream ss1;
   UniversalPrint(s1, &ss1);
   EXPECT_EQ(PrintPointer(s1) + " pointing to \"abc\"", std::string(ss1.str()));
 
   char* s2 = const_cast<char*>(s1);
   ::std::stringstream ss2;
   UniversalPrint(s2, &ss2);
   EXPECT_EQ(PrintPointer(s2) + " pointing to \"abc\"", std::string(ss2.str()));
 
   const char* s3 = NULL;
   ::std::stringstream ss3;
   UniversalPrint(s3, &ss3);
   EXPECT_EQ("NULL", ss3.str());
 }
 
 TEST(UniversalPrintTest, WorksForCharArray) {
   const char str[] = "\"Line\0 1\"\nLine 2";
   ::std::stringstream ss1;
   UniversalPrint(str, &ss1);
   EXPECT_EQ("\"\\\"Line\\0 1\\\"\\nLine 2\"", ss1.str());
 
   const char mutable_str[] = "\"Line\0 1\"\nLine 2";
   ::std::stringstream ss2;
   UniversalPrint(mutable_str, &ss2);
   EXPECT_EQ("\"\\\"Line\\0 1\\\"\\nLine 2\"", ss2.str());
 }
 
 #if GTEST_HAS_TR1_TUPLE
 
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithTr1, PrintsEmptyTuple) {
   Strings result = UniversalTersePrintTupleFieldsToStrings(
       ::std::tr1::make_tuple());
   EXPECT_EQ(0u, result.size());
 }
 
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithTr1, PrintsOneTuple) {
   Strings result = UniversalTersePrintTupleFieldsToStrings(
       ::std::tr1::make_tuple(1));
   ASSERT_EQ(1u, result.size());
   EXPECT_EQ("1", result[0]);
 }
 
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithTr1, PrintsTwoTuple) {
   Strings result = UniversalTersePrintTupleFieldsToStrings(
       ::std::tr1::make_tuple(1, 'a'));
   ASSERT_EQ(2u, result.size());
   EXPECT_EQ("1", result[0]);
   EXPECT_EQ("'a' (97, 0x61)", result[1]);
 }
 
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithTr1, PrintsTersely) {
   const int n = 1;
   Strings result = UniversalTersePrintTupleFieldsToStrings(
       ::std::tr1::tuple<const int&, const char*>(n, "a"));
   ASSERT_EQ(2u, result.size());
   EXPECT_EQ("1", result[0]);
   EXPECT_EQ("\"a\"", result[1]);
 }
 
 #endif  // GTEST_HAS_TR1_TUPLE
 
 #if GTEST_HAS_STD_TUPLE_
 
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithStd, PrintsEmptyTuple) {
   Strings result = UniversalTersePrintTupleFieldsToStrings(::std::make_tuple());
   EXPECT_EQ(0u, result.size());
 }
 
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithStd, PrintsOneTuple) {
   Strings result = UniversalTersePrintTupleFieldsToStrings(
       ::std::make_tuple(1));
   ASSERT_EQ(1u, result.size());
   EXPECT_EQ("1", result[0]);
 }
 
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithStd, PrintsTwoTuple) {
   Strings result = UniversalTersePrintTupleFieldsToStrings(
       ::std::make_tuple(1, 'a'));
   ASSERT_EQ(2u, result.size());
   EXPECT_EQ("1", result[0]);
   EXPECT_EQ("'a' (97, 0x61)", result[1]);
 }
 
 TEST(UniversalTersePrintTupleFieldsToStringsTestWithStd, PrintsTersely) {
   const int n = 1;
   Strings result = UniversalTersePrintTupleFieldsToStrings(
       ::std::tuple<const int&, const char*>(n, "a"));
   ASSERT_EQ(2u, result.size());
   EXPECT_EQ("1", result[0]);
   EXPECT_EQ("\"a\"", result[1]);
 }
 
 #endif  // GTEST_HAS_STD_TUPLE_
 
 #if GTEST_HAS_ABSL
 
 TEST(PrintOptionalTest, Basic) {
   absl::optional<int> value;
   EXPECT_EQ("(nullopt)", PrintToString(value));
   value = {7};
   EXPECT_EQ("(7)", PrintToString(value));
   EXPECT_EQ("(1.1)", PrintToString(absl::optional<double>{1.1}));
   EXPECT_EQ("(\"A\")", PrintToString(absl::optional<std::string>{"A"}));
 }
 #endif  // GTEST_HAS_ABSL
 
 }  // namespace gtest_printers_test
 }  // namespace testing