Removes testing::internal::String::Format(), which causes problems as it truncates the result at 4096 chars. Also update an obsolete link in comment.

git-svn-id: http://googletest.googlecode.com/svn/trunk@636 861a406c-534a-0410-8894-cb66d6ee9925

13 files changed, 176 insertions, 232 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 64527f7..b470ad2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -130,6 +130,7 @@ if (gtest_build_tests)
   cxx_test(gtest_repeat_test gtest)
   cxx_test(gtest_sole_header_test gtest_main)
   cxx_test(gtest_stress_test gtest)
+  cxx_test(gtest_test_macro_stack_footprint_test gtest)
   cxx_test(gtest-test-part_test gtest_main)
   cxx_test(gtest_throw_on_failure_ex_test gtest)
   cxx_test(gtest-typed-test_test gtest_main
diff --git a/Makefile.am b/Makefile.am
index 788c475..c122254 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -82,6 +82,7 @@ EXTRA_DIST += \
   test/gtest_shuffle_test_.cc \
   test/gtest_sole_header_test.cc \
   test/gtest_stress_test.cc \
+  test/gtest_test_macro_stack_footprint_test.cc \
   test/gtest_throw_on_failure_ex_test.cc \
   test/gtest_throw_on_failure_test_.cc \
   test/gtest_uninitialized_test_.cc \
diff --git a/include/gtest/gtest.h b/include/gtest/gtest.h
index 9ecb145..09e74d9 100644
--- a/include/gtest/gtest.h
+++ b/include/gtest/gtest.h
@@ -680,7 +680,8 @@ class GTEST_API_ TestInfo {
   friend class TestCase;
   friend class internal::UnitTestImpl;
   friend TestInfo* internal::MakeAndRegisterTestInfo(
-      const char* test_case_name, const char* name,
+      const char* test_case_name,
+      const char* name,
       const char* type_param,
       const char* value_param,
       internal::TypeId fixture_class_id,
@@ -690,9 +691,10 @@ class GTEST_API_ TestInfo {
 
   // Constructs a TestInfo object. The newly constructed instance assumes
   // ownership of the factory object.
-  TestInfo(const char* test_case_name, const char* name,
-           const char* a_type_param,
-           const char* a_value_param,
+  TestInfo(const std::string& test_case_name,
+           const std::string& name,
+           const char* a_type_param,   // NULL if not a type-parameterized test
+           const char* a_value_param,  // NULL if not a value-parameterized test
            internal::TypeId fixture_class_id,
            internal::TestFactoryBase* factory);
 
diff --git a/include/gtest/internal/gtest-internal.h b/include/gtest/internal/gtest-internal.h
index 4e57d3c..ca4e1fd 100644
--- a/include/gtest/internal/gtest-internal.h
+++ b/include/gtest/internal/gtest-internal.h
@@ -493,7 +493,7 @@ typedef void (*TearDownTestCaseFunc)();
 //   test_case_name:   name of the test case
 //   name:             name of the test
 //   type_param        the name of the test's type parameter, or NULL if
-//                     this is not  a typed or a type-parameterized test.
+//                     this is not a typed or a type-parameterized test.
 //   value_param       text representation of the test's value parameter,
 //                     or NULL if this is not a type-parameterized test.
 //   fixture_class_id: ID of the test fixture class
@@ -503,7 +503,8 @@ typedef void (*TearDownTestCaseFunc)();
 //                     The newly created TestInfo instance will assume
 //                     ownership of the factory object.
 GTEST_API_ TestInfo* MakeAndRegisterTestInfo(
-    const char* test_case_name, const char* name,
+    const char* test_case_name,
+    const char* name,
     const char* type_param,
     const char* value_param,
     TypeId fixture_class_id,
@@ -591,8 +592,8 @@ class TypeParameterizedTest {
     // First, registers the first type-parameterized test in the type
     // list.
     MakeAndRegisterTestInfo(
-        String::Format("%s%s%s/%d", prefix, prefix[0] == '\0' ? "" : "/",
-                       case_name, index).c_str(),
+        (std::string(prefix) + (prefix[0] == '\0' ? "" : "/") + case_name + "/"
+         + StreamableToString(index)).c_str(),
         GetPrefixUntilComma(test_names).c_str(),
         GetTypeName<Type>().c_str(),
         NULL,  // No value parameter.
diff --git a/include/gtest/internal/gtest-param-util.h b/include/gtest/internal/gtest-param-util.h
index 0ef9718..d5e1028 100644
--- a/include/gtest/internal/gtest-param-util.h
+++ b/include/gtest/internal/gtest-param-util.h
@@ -494,10 +494,10 @@ class ParameterizedTestCaseInfo : public ParameterizedTestCaseInfoBase {
         const string& instantiation_name = gen_it->first;
         ParamGenerator<ParamType> generator((*gen_it->second)());
 
-        Message test_case_name_stream;
+        string test_case_name;
         if ( !instantiation_name.empty() )
-          test_case_name_stream << instantiation_name << "/";
-        test_case_name_stream << test_info->test_case_base_name;
+          test_case_name = instantiation_name + "/";
+        test_case_name += test_info->test_case_base_name;
 
         int i = 0;
         for (typename ParamGenerator<ParamType>::iterator param_it =
@@ -506,7 +506,7 @@ class ParameterizedTestCaseInfo : public ParameterizedTestCaseInfoBase {
           Message test_name_stream;
           test_name_stream << test_info->test_base_name << "/" << i;
           MakeAndRegisterTestInfo(
-              test_case_name_stream.GetString().c_str(),
+              test_case_name.c_str(),
               test_name_stream.GetString().c_str(),
               NULL,  // No type parameter.
               PrintToString(*param_it).c_str(),
diff --git a/include/gtest/internal/gtest-string.h b/include/gtest/internal/gtest-string.h
index 472dd05..7b74085 100644
--- a/include/gtest/internal/gtest-string.h
+++ b/include/gtest/internal/gtest-string.h
@@ -144,16 +144,14 @@ class GTEST_API_ String {
   static bool EndsWithCaseInsensitive(
       const std::string& str, const std::string& suffix);
 
-  // Formats a list of arguments to an std::string, using the same format
-  // spec string as for printf.
-  //
-  // We do not use the StringPrintf class as it is not universally
-  // available.
-  //
-  // The result is limited to 4096 characters (including the tailing
-  // 0).  If 4096 characters are not enough to format the input,
-  // "<buffer exceeded>" is returned.
-  static std::string Format(const char* format, ...);
+  // Formats an int value as "%02d".
+  static std::string FormatIntWidth2(int value);  // "%02d" for width == 2
+
+  // Formats an int value as "%X".
+  static std::string FormatHexInt(int value);
+
+  // Formats a byte as "%02X".
+  static std::string FormatByte(unsigned char value);
 
  private:
   String();  // Not meant to be instantiated.
diff --git a/src/gtest-death-test.cc b/src/gtest-death-test.cc
index 8b52431..a6023fc 100644
--- a/src/gtest-death-test.cc
+++ b/src/gtest-death-test.cc
@@ -272,9 +272,10 @@ void DeathTestAbort(const std::string& message) {
 # define GTEST_DEATH_TEST_CHECK_(expression) \
   do { \
     if (!::testing::internal::IsTrue(expression)) { \
-      DeathTestAbort(::testing::internal::String::Format(       \
-          "CHECK failed: File %s, line %d: %s", \
-          __FILE__, __LINE__, #expression)); \
+      DeathTestAbort( \
+          ::std::string("CHECK failed: File ") + __FILE__ +  ", line " \
+          + ::testing::internal::StreamableToString(__LINE__) + ": " \
+          + #expression); \
     } \
   } while (::testing::internal::AlwaysFalse())
 
@@ -292,9 +293,10 @@ void DeathTestAbort(const std::string& message) {
       gtest_retval = (expression); \
     } while (gtest_retval == -1 && errno == EINTR); \
     if (gtest_retval == -1) { \
-      DeathTestAbort(::testing::internal::String::Format(       \
-          "CHECK failed: File %s, line %d: %s != -1", \
-          __FILE__, __LINE__, #expression)); \
+      DeathTestAbort( \
+          ::std::string("CHECK failed: File ") + __FILE__ + ", line " \
+          + ::testing::internal::StreamableToString(__LINE__) + ": " \
+          + #expression + " != -1"); \
     } \
   } while (::testing::internal::AlwaysFalse())
 
@@ -716,14 +718,14 @@ DeathTest::TestRole WindowsDeathTest::AssumeRole() {
       info->test_case_name() + "." + info->name();
   const std::string internal_flag =
       std::string("--") + GTEST_FLAG_PREFIX_ + kInternalRunDeathTestFlag +
-      "=" + file_ + "|" + String::Format("%d|%d|%u|%Iu|%Iu", line_,
-      death_test_index,
-      static_cast<unsigned int>(::GetCurrentProcessId()),
-      // size_t has the same with as pointers on both 32-bit and 64-bit
+      "=" + file_ + "|" + StreamableToString(line_) + "|" +
+      StreamableToString(death_test_index) + "|" +
+      StreamableToString(static_cast<unsigned int>(::GetCurrentProcessId())) +
+      // size_t has the same width as pointers on both 32-bit and 64-bit
       // Windows platforms.
       // See http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx.
-      reinterpret_cast<size_t>(write_handle),
-      reinterpret_cast<size_t>(event_handle_.Get()));
+      "|" + StreamableToString(reinterpret_cast<size_t>(write_handle)) +
+      "|" + StreamableToString(reinterpret_cast<size_t>(event_handle_.Get()));
 
   char executable_path[_MAX_PATH + 1];  // NOLINT
   GTEST_DEATH_TEST_CHECK_(
@@ -1114,13 +1116,13 @@ DeathTest::TestRole ExecDeathTest::AssumeRole() {
   GTEST_DEATH_TEST_CHECK_(fcntl(pipe_fd[1], F_SETFD, 0) != -1);
 
   const std::string filter_flag =
-      String::Format("--%s%s=%s.%s",
-                     GTEST_FLAG_PREFIX_, kFilterFlag,
-                     info->test_case_name(), info->name());
+      std::string("--") + GTEST_FLAG_PREFIX_ + kFilterFlag + "="
+      + info->test_case_name() + "." + info->name();
   const std::string internal_flag =
-      String::Format("--%s%s=%s|%d|%d|%d",
-                     GTEST_FLAG_PREFIX_, kInternalRunDeathTestFlag,
-                     file_, line_, death_test_index, pipe_fd[1]);
+      std::string("--") + GTEST_FLAG_PREFIX_ + kInternalRunDeathTestFlag + "="
+      + file_ + "|" + StreamableToString(line_) + "|"
+      + StreamableToString(death_test_index) + "|"
+      + StreamableToString(pipe_fd[1]);
   Arguments args;
   args.AddArguments(GetArgvsForDeathTestChildProcess());
   args.AddArgument(filter_flag.c_str());
@@ -1159,9 +1161,10 @@ bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex,
 
   if (flag != NULL) {
     if (death_test_index > flag->index()) {
-      DeathTest::set_last_death_test_message(String::Format(
-          "Death test count (%d) somehow exceeded expected maximum (%d)",
-          death_test_index, flag->index()));
+      DeathTest::set_last_death_test_message(
+          "Death test count (" + StreamableToString(death_test_index)
+          + ") somehow exceeded expected maximum ("
+          + StreamableToString(flag->index()) + ")");
       return false;
     }
 
@@ -1190,9 +1193,9 @@ bool DefaultDeathTestFactory::Create(const char* statement, const RE* regex,
 # endif  // GTEST_OS_WINDOWS
 
   else {  // NOLINT - this is more readable than unbalanced brackets inside #if.
-    DeathTest::set_last_death_test_message(String::Format(
-        "Unknown death test style \"%s\" encountered",
-        GTEST_FLAG(death_test_style).c_str()));
+    DeathTest::set_last_death_test_message(
+        "Unknown death test style \"" + GTEST_FLAG(death_test_style)
+        + "\" encountered");
     return false;
   }
 
@@ -1230,8 +1233,8 @@ int GetStatusFileDescriptor(unsigned int parent_process_id,
                                                    FALSE,  // Non-inheritable.
                                                    parent_process_id));
   if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) {
-    DeathTestAbort(String::Format("Unable to open parent process %u",
-                                  parent_process_id));
+    DeathTestAbort("Unable to open parent process " +
+                   StreamableToString(parent_process_id));
   }
 
   // TODO(vladl@google.com): Replace the following check with a
@@ -1251,9 +1254,10 @@ int GetStatusFileDescriptor(unsigned int parent_process_id,
                                  // DUPLICATE_SAME_ACCESS is used.
                          FALSE,  // Request non-inheritable handler.
                          DUPLICATE_SAME_ACCESS)) {
-    DeathTestAbort(String::Format(
-        "Unable to duplicate the pipe handle %Iu from the parent process %u",
-        write_handle_as_size_t, parent_process_id));
+    DeathTestAbort("Unable to duplicate the pipe handle " +
+                   StreamableToString(write_handle_as_size_t) +
+                   " from the parent process " +
+                   StreamableToString(parent_process_id));
   }
 
   const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t);
@@ -1264,17 +1268,18 @@ int GetStatusFileDescriptor(unsigned int parent_process_id,
                          0x0,
                          FALSE,
                          DUPLICATE_SAME_ACCESS)) {
-    DeathTestAbort(String::Format(
-        "Unable to duplicate the event handle %Iu from the parent process %u",
-        event_handle_as_size_t, parent_process_id));
+    DeathTestAbort("Unable to duplicate the event handle " +
+                   StreamableToString(event_handle_as_size_t) +
+                   " from the parent process " +
+                   StreamableToString(parent_process_id));
   }
 
   const int write_fd =
       ::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND);
   if (write_fd == -1) {
-    DeathTestAbort(String::Format(
-        "Unable to convert pipe handle %Iu to a file descriptor",
-        write_handle_as_size_t));
+    DeathTestAbort("Unable to convert pipe handle " +
+                   StreamableToString(write_handle_as_size_t) +
+                   " to a file descriptor");
   }
 
   // Signals the parent that the write end of the pipe has been acquired
@@ -1311,9 +1316,8 @@ InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {
       || !ParseNaturalNumber(fields[3], &parent_process_id)
       || !ParseNaturalNumber(fields[4], &write_handle_as_size_t)
       || !ParseNaturalNumber(fields[5], &event_handle_as_size_t)) {
-    DeathTestAbort(String::Format(
-        "Bad --gtest_internal_run_death_test flag: %s",
-        GTEST_FLAG(internal_run_death_test).c_str()));
+    DeathTestAbort("Bad --gtest_internal_run_death_test flag: " +
+                   GTEST_FLAG(internal_run_death_test));
   }
   write_fd = GetStatusFileDescriptor(parent_process_id,
                                      write_handle_as_size_t,
@@ -1324,9 +1328,8 @@ InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag() {
       || !ParseNaturalNumber(fields[1], &line)
       || !ParseNaturalNumber(fields[2], &index)
       || !ParseNaturalNumber(fields[3], &write_fd)) {
-    DeathTestAbort(String::Format(
-        "Bad --gtest_internal_run_death_test flag: %s",
-        GTEST_FLAG(internal_run_death_test).c_str()));
+    DeathTestAbort("Bad --gtest_internal_run_death_test flag: "
+        + GTEST_FLAG(internal_run_death_test));
   }
 
 # endif  // GTEST_OS_WINDOWS
diff --git a/src/gtest-filepath.cc b/src/gtest-filepath.cc
index 4d40cb9..708389d 100644
--- a/src/gtest-filepath.cc
+++ b/src/gtest-filepath.cc
@@ -182,7 +182,7 @@ FilePath FilePath::MakeFileName(const FilePath& directory,
   if (number == 0) {
     file = base_name.string() + "." + extension;
   } else {
-    file = base_name.string() + "_" + String::Format("%d", number).c_str()
+    file = base_name.string() + "_" + StreamableToString(number)
         + "." + extension;
   }
   return ConcatPaths(directory, FilePath(file));
diff --git a/src/gtest-internal-inl.h b/src/gtest-internal-inl.h
index 54717c9..2491eee 100644
--- a/src/gtest-internal-inl.h
+++ b/src/gtest-internal-inl.h
@@ -222,12 +222,10 @@ class GTestFlagSaver {
 // Converts a Unicode code point to a narrow string in UTF-8 encoding.
 // code_point parameter is of type UInt32 because wchar_t may not be
 // wide enough to contain a code point.
-// The output buffer str must containt at least 32 characters.
-// The function returns the address of the output buffer.
 // If the code_point is not a valid Unicode code point
-// (i.e. outside of Unicode range U+0 to U+10FFFF) it will be output
-// as '(Invalid Unicode 0xXXXXXXXX)'.
-GTEST_API_ char* CodePointToUtf8(UInt32 code_point, char* str);
+// (i.e. outside of Unicode range U+0 to U+10FFFF) it will be converted
+// to "(Invalid Unicode 0xXXXXXXXX)".
+GTEST_API_ std::string CodePointToUtf8(UInt32 code_point);
 
 // Converts a wide string to a narrow string in UTF-8 encoding.
 // The wide string is assumed to have the following encoding:
diff --git a/src/gtest-port.cc b/src/gtest-port.cc
index fa8f29c..0c4df5f 100644
--- a/src/gtest-port.cc
+++ b/src/gtest-port.cc
@@ -454,15 +454,15 @@ const char kUnknownFile[] = "unknown file";
 // Formats a source file path and a line number as they would appear
 // in an error message from the compiler used to compile this code.
 GTEST_API_ ::std::string FormatFileLocation(const char* file, int line) {
-  const char* const file_name = file == NULL ? kUnknownFile : file;
+  const std::string file_name(file == NULL ? kUnknownFile : file);
 
   if (line < 0) {
-    return String::Format("%s:", file_name).c_str();
+    return file_name + ":";
   }
 #ifdef _MSC_VER
-  return String::Format("%s(%d):", file_name, line).c_str();
+  return file_name + "(" + StreamableToString(line) + "):";
 #else
-  return String::Format("%s:%d:", file_name, line).c_str();
+  return file_name + ":" + StreamableToString(line) + ":";
 #endif  // _MSC_VER
 }
 
@@ -473,12 +473,12 @@ GTEST_API_ ::std::string FormatFileLocation(const char* file, int line) {
 // to the file location it produces, unlike FormatFileLocation().
 GTEST_API_ ::std::string FormatCompilerIndependentFileLocation(
     const char* file, int line) {
-  const char* const file_name = file == NULL ? kUnknownFile : file;
+  const std::string file_name(file == NULL ? kUnknownFile : file);
 
   if (line < 0)
     return file_name;
   else
-    return String::Format("%s:%d", file_name, line).c_str();
+    return file_name + ":" + StreamableToString(line);
 }
 
 
diff --git a/src/gtest-printers.cc b/src/gtest-printers.cc
index 898d61d..75fa408 100644
--- a/src/gtest-printers.cc
+++ b/src/gtest-printers.cc
@@ -176,7 +176,7 @@ static CharFormat PrintAsCharLiteralTo(Char c, ostream* os) {
         *os << static_cast<char>(c);
         return kAsIs;
       } else {
-        *os << String::Format("\\x%X", static_cast<UnsignedChar>(c));
+        *os << "\\x" + String::FormatHexInt(static_cast<UnsignedChar>(c));
         return kHexEscape;
       }
   }
@@ -221,7 +221,7 @@ void PrintCharAndCodeTo(Char c, ostream* os) {
   // obvious).
   if (c == 0)
     return;
-  *os << " (" << String::Format("%d", c).c_str();
+  *os << " (" << static_cast<int>(c);
 
   // For more convenience, we print c's code again in hexidecimal,
   // unless c was already printed in the form '\x##' or the code is in
@@ -229,8 +229,7 @@ void PrintCharAndCodeTo(Char c, ostream* os) {
   if (format == kHexEscape || (1 <= c && c <= 9)) {
     // Do nothing.
   } else {
-    *os << String::Format(", 0x%X",
-                          static_cast<UnsignedChar>(c)).c_str();
+    *os << ", 0x" << String::FormatHexInt(static_cast<UnsignedChar>(c));
   }
   *os << ")";
 }
diff --git a/src/gtest.cc b/src/gtest.cc
index 0567e83..8bf4b80 100644
--- a/src/gtest.cc
+++ b/src/gtest.cc
@@ -1309,7 +1309,7 @@ AssertionResult HRESULTFailureHelper(const char* expr,
   // want inserts expanded.
   const DWORD kFlags = FORMAT_MESSAGE_FROM_SYSTEM |
                        FORMAT_MESSAGE_IGNORE_INSERTS;
-  const DWORD kBufSize = 4096;  // String::Format can't exceed this length.
+  const DWORD kBufSize = 4096;
   // Gets the system's human readable message string for this HRESULT.
   char error_text[kBufSize] = { '\0' };
   DWORD message_length = ::FormatMessageA(kFlags,
@@ -1319,7 +1319,7 @@ AssertionResult HRESULTFailureHelper(const char* expr,
                                           error_text,  // output buffer
                                           kBufSize,  // buf size
                                           NULL);  // no arguments for inserts
-  // Trims tailing white space (FormatMessage leaves a trailing cr-lf)
+  // Trims tailing white space (FormatMessage leaves a trailing CR-LF)
   for (; message_length && IsSpace(error_text[message_length - 1]);
           --message_length) {
     error_text[message_length - 1] = '\0';
@@ -1327,10 +1327,10 @@ AssertionResult HRESULTFailureHelper(const char* expr,
 
 # endif  // GTEST_OS_WINDOWS_MOBILE
 
-  const std::string error_hex(String::Format("0x%08X ", hr));
+  const std::string error_hex("0x" + String::FormatHexInt(hr));
   return ::testing::AssertionFailure()
       << "Expected: " << expr << " " << expected << ".\n"
-      << "  Actual: " << error_hex << error_text << "\n";
+      << "  Actual: " << error_hex << " " << error_text << "\n";
 }
 
 }  // namespace
@@ -1387,12 +1387,15 @@ inline UInt32 ChopLowBits(UInt32* bits, int n) {
 // Converts a Unicode code point to a narrow string in UTF-8 encoding.
 // code_point parameter is of type UInt32 because wchar_t may not be
 // wide enough to contain a code point.
-// The output buffer str must containt at least 32 characters.
-// The function returns the address of the output buffer.
 // If the code_point is not a valid Unicode code point
-// (i.e. outside of Unicode range U+0 to U+10FFFF) it will be output
-// as '(Invalid Unicode 0xXXXXXXXX)'.
-char* CodePointToUtf8(UInt32 code_point, char* str) {
+// (i.e. outside of Unicode range U+0 to U+10FFFF) it will be converted
+// to "(Invalid Unicode 0xXXXXXXXX)".
+std::string CodePointToUtf8(UInt32 code_point) {
+  if (code_point > kMaxCodePoint4) {
+    return "(Invalid Unicode 0x" + String::FormatHexInt(code_point) + ")";
+  }
+
+  char str[5];  // Big enough for the largest valid code point.
   if (code_point <= kMaxCodePoint1) {
     str[1] = '\0';
     str[0] = static_cast<char>(code_point);                          // 0xxxxxxx
@@ -1405,22 +1408,12 @@ char* CodePointToUtf8(UInt32 code_point, char* str) {
     str[2] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
     str[1] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
     str[0] = static_cast<char>(0xE0 | code_point);                   // 1110xxxx
-  } else if (code_point <= kMaxCodePoint4) {
+  } else {  // code_point <= kMaxCodePoint4
     str[4] = '\0';
     str[3] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
     str[2] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
     str[1] = static_cast<char>(0x80 | ChopLowBits(&code_point, 6));  // 10xxxxxx
     str[0] = static_cast<char>(0xF0 | code_point);                   // 11110xxx
-  } else {
-    // The longest string String::Format can produce when invoked
-    // with these parameters is 28 character long (not including
-    // the terminating nul character). We are asking for 32 character
-    // buffer just in case. This is also enough for strncpy to
-    // null-terminate the destination string.
-    posix::StrNCpy(
-        str, String::Format("(Invalid Unicode 0x%X)", code_point).c_str(), 32);
-    str[31] = '\0';  // Makes sure no change in the format to strncpy leaves
-                     // the result unterminated.
   }
   return str;
 }
@@ -1479,8 +1472,7 @@ std::string WideStringToUtf8(const wchar_t* str, int num_chars) {
       unicode_code_point = static_cast<UInt32>(str[i]);
     }
 
-    char buffer[32];  // CodePointToUtf8 requires a buffer this big.
-    stream << CodePointToUtf8(unicode_code_point, buffer);
+    stream << CodePointToUtf8(unicode_code_point);
   }
   return StringStreamToString(&stream);
 }
@@ -1597,47 +1589,26 @@ bool String::EndsWithCaseInsensitive(
                                       suffix.c_str());
 }
 
-// Formats a list of arguments to an std::string, using the same format
-// spec string as for printf.
-//
-// We do not use the StringPrintf class as it is not universally
-// available.
-//
-// The result is limited to 4096 characters (including the tailing 0).
-// If 4096 characters are not enough to format the input, or if
-// there's an error, "<formatting error or buffer exceeded>" is
-// returned.
-std::string String::Format(const char * format, ...) {
-  va_list args;
-  va_start(args, format);
-
-  char buffer[4096];
-  const int kBufferSize = sizeof(buffer)/sizeof(buffer[0]);
-
-  // MSVC 8 deprecates vsnprintf(), so we want to suppress warning
-  // 4996 (deprecated function) there.
-#ifdef _MSC_VER  // We are using MSVC.
-# pragma warning(push)          // Saves the current warning state.
-# pragma warning(disable:4996)  // Temporarily disables warning 4996.
-
-  const int size = vsnprintf(buffer, kBufferSize, format, args);
+// Formats an int value as "%02d".
+std::string String::FormatIntWidth2(int value) {
+  std::stringstream ss;
+  ss << std::setfill('0') << std::setw(2) << value;
+  return ss.str();
+}
 
-# pragma warning(pop)           // Restores the warning state.
-#else  // We are not using MSVC.
-  const int size = vsnprintf(buffer, kBufferSize, format, args);
-#endif  // _MSC_VER
-  va_end(args);
+// Formats an int value as "%X".
+std::string String::FormatHexInt(int value) {
+  std::stringstream ss;
+  ss << std::hex << std::uppercase << value;
+  return ss.str();
+}
 
-  // vsnprintf()'s behavior is not portable.  When the buffer is not
-  // big enough, it returns a negative value in MSVC, and returns the
-  // needed buffer size on Linux.  When there is an output error, it
-  // always returns a negative value.  For simplicity, we lump the two
-  // error cases together.
-  if (size < 0 || size >= kBufferSize) {
-    return "<formatting error or buffer exceeded>";
-  } else {
-    return std::string(buffer, size);
-  }
+// Formats a byte as "%02X".
+std::string String::FormatByte(unsigned char value) {
+  std::stringstream ss;
+  ss << std::setfill('0') << std::setw(2) << std::hex << std::uppercase
+     << static_cast<unsigned int>(value);
+  return ss.str();
 }
 
 // Converts the buffer in a stringstream to an std::string, converting NUL
@@ -2091,10 +2062,8 @@ bool Test::HasNonfatalFailure() {
 
 // Constructs a TestInfo object. It assumes ownership of the test factory
 // object.
-// TODO(vladl@google.com): Make a_test_case_name and a_name const string&'s
-// to signify they cannot be NULLs.
-TestInfo::TestInfo(const char* a_test_case_name,
-                   const char* a_name,
+TestInfo::TestInfo(const std::string& a_test_case_name,
+                   const std::string& a_name,
                    const char* a_type_param,
                    const char* a_value_param,
                    internal::TypeId fixture_class_id,
@@ -2133,7 +2102,8 @@ namespace internal {
 //                     The newly created TestInfo instance will assume
 //                     ownership of the factory object.
 TestInfo* MakeAndRegisterTestInfo(
-    const char* test_case_name, const char* name,
+    const char* test_case_name,
+    const char* name,
     const char* type_param,
     const char* value_param,
     TypeId fixture_class_id,
@@ -2385,8 +2355,8 @@ void TestCase::UnshuffleTests() {
 static std::string FormatCountableNoun(int count,
                                        const char * singular_form,
                                        const char * plural_form) {
-  return internal::String::Format("%d %s", count,
-                                  count == 1 ? singular_form : plural_form);
+  return internal::StreamableToString(count) + " " +
+      (count == 1 ? singular_form : plural_form);
 }
 
 // Formats the count of tests.
@@ -3056,7 +3026,8 @@ std::string XmlUnitTestResultPrinter::EscapeXml(
         default:
           if (IsValidXmlCharacter(*src)) {
             if (is_attribute && IsNormalizableWhitespace(*src))
-              m << String::Format("&#x%02X;", unsigned(*src));
+              m << "&#x" << String::FormatByte(static_cast<unsigned char>(*src))
+                << ";";
             else
               m << *src;
           }
@@ -3121,13 +3092,13 @@ std::string FormatEpochTimeInMillisAsIso8601(TimeInMillis ms) {
   if (time_struct == NULL)
     return "";  // Invalid ms value
 
-  return String::Format("%d-%02d-%02dT%02d:%02d:%02d",  // YYYY-MM-DDThh:mm:ss
-                        time_struct->tm_year + 1900,
-                        time_struct->tm_mon + 1,
-                        time_struct->tm_mday,
-                        time_struct->tm_hour,
-                        time_struct->tm_min,
-                        time_struct->tm_sec);
+  // YYYY-MM-DDThh:mm:ss
+  return StreamableToString(time_struct->tm_year + 1900) + "-" +
+      String::FormatIntWidth2(time_struct->tm_mon + 1) + "-" +
+      String::FormatIntWidth2(time_struct->tm_mday) + "T" +
+      String::FormatIntWidth2(time_struct->tm_hour) + ":" +
+      String::FormatIntWidth2(time_struct->tm_min) + ":" +
+      String::FormatIntWidth2(time_struct->tm_sec);
 }
 
 // Streams an XML CDATA section, escaping invalid CDATA sequences as needed.
@@ -3268,7 +3239,7 @@ class StreamingListener : public EmptyTestEventListener {
   StreamingListener(const string& host, const string& port)
       : sockfd_(-1), host_name_(host), port_num_(port) {
     MakeConnection();
-    Send("gtest_streaming_protocol_version=1.0\n");
+    SendLn("gtest_streaming_protocol_version=1.0");
   }
 
   virtual ~StreamingListener() {
@@ -3277,59 +3248,58 @@ class StreamingListener : public EmptyTestEventListener {
   }
 
   void OnTestProgramStart(const UnitTest& /* unit_test */) {
-    Send("event=TestProgramStart\n");
+    SendLn("event=TestProgramStart");
   }
 
   void OnTestProgramEnd(const UnitTest& unit_test) {
     // Note that Google Test current only report elapsed time for each
     // test iteration, not for the entire test program.
-    Send(String::Format("event=TestProgramEnd&passed=%d\n",
-                        unit_test.Passed()));
+    SendLn("event=TestProgramEnd&passed=" +
+           StreamableToString(unit_test.Passed()));
 
     // Notify the streaming server to stop.
     CloseConnection();
   }
 
   void OnTestIterationStart(const UnitTest& /* unit_test */, int iteration) {
-    Send(String::Format("event=TestIterationStart&iteration=%d\n",
-                        iteration));
+    SendLn("event=TestIterationStart&iteration=" +
+           StreamableToString(iteration));
   }
 
   void OnTestIterationEnd(const UnitTest& unit_test, int /* iteration */) {
-    Send(String::Format("event=TestIterationEnd&passed=%d&elapsed_time=%sms\n",
-                        unit_test.Passed(),
-                        StreamableToString(unit_test.elapsed_time()).c_str()));
+    SendLn("event=TestIterationEnd&passed=" +
+           StreamableToString(unit_test.Passed()) + "&elapsed_time=" +
+           StreamableToString(unit_test.elapsed_time()) + "ms");
   }
 
   void OnTestCaseStart(const TestCase& test_case) {
-    Send(String::Format("event=TestCaseStart&name=%s\n", test_case.name()));
+    SendLn(std::string("event=TestCaseStart&name=") + test_case.name());
   }
 
   void OnTestCaseEnd(const TestCase& test_case) {
-    Send(String::Format("event=TestCaseEnd&passed=%d&elapsed_time=%sms\n",
-                        test_case.Passed(),
-                        StreamableToString(test_case.elapsed_time()).c_str()));
+    SendLn("event=TestCaseEnd&passed=" + StreamableToString(test_case.Passed())
+           + "&elapsed_time=" + StreamableToString(test_case.elapsed_time())
+           + "ms");
   }
 
   void OnTestStart(const TestInfo& test_info) {
-    Send(String::Format("event=TestStart&name=%s\n", test_info.name()));
+    SendLn(std::string("event=TestStart&name=") + test_info.name());
   }
 
   void OnTestEnd(const TestInfo& test_info) {
-    Send(String::Format(
-        "event=TestEnd&passed=%d&elapsed_time=%sms\n",
-        (test_info.result())->Passed(),
-        StreamableToString((test_info.result())->elapsed_time()).c_str()));
+    SendLn("event=TestEnd&passed=" +
+           StreamableToString((test_info.result())->Passed()) +
+           "&elapsed_time=" +
+           StreamableToString((test_info.result())->elapsed_time()) + "ms");
   }
 
   void OnTestPartResult(const TestPartResult& test_part_result) {
     const char* file_name = test_part_result.file_name();
     if (file_name == NULL)
       file_name = "";
-    Send(String::Format("event=TestPartResult&file=%s&line=%d&message=",
-                        UrlEncode(file_name).c_str(),
-                        test_part_result.line_number()));
-    Send(UrlEncode(test_part_result.message()) + "\n");
+    SendLn("event=TestPartResult&file=" + UrlEncode(file_name) +
+           "&line=" + StreamableToString(test_part_result.line_number()) +
+           "&message=" + UrlEncode(test_part_result.message()));
   }
 
  private:
@@ -3358,6 +3328,11 @@ class StreamingListener : public EmptyTestEventListener {
     }
   }
 
+  // Sends a string and a newline to the socket.
+  void SendLn(const string& message) {
+    Send(message + "\n");
+  }
+
   int sockfd_;   // socket file descriptor
   const string host_name_;
   const string port_num_;
@@ -3379,7 +3354,7 @@ string StreamingListener::UrlEncode(const char* str) {
       case '=':
       case '&':
       case '\n':
-        result.append(String::Format("%%%02x", static_cast<unsigned char>(ch)));
+        result.append("%" + String::FormatByte(static_cast<unsigned char>(ch)));
         break;
       default:
         result.push_back(ch);
diff --git a/test/gtest_unittest.cc b/test/gtest_unittest.cc
index f4f3043..4e9564f 100644
--- a/test/gtest_unittest.cc
+++ b/test/gtest_unittest.cc
@@ -454,45 +454,41 @@ TEST(NullLiteralTest, IsFalseForNonNullLiterals) {
 
 // Tests that the NUL character L'\0' is encoded correctly.
 TEST(CodePointToUtf8Test, CanEncodeNul) {
-  char buffer[32];
-  EXPECT_STREQ("", CodePointToUtf8(L'\0', buffer));
+  EXPECT_EQ("", CodePointToUtf8(L'\0'));
 }
 
 // Tests that ASCII characters are encoded correctly.
 TEST(CodePointToUtf8Test, CanEncodeAscii) {
-  char buffer[32];
-  EXPECT_STREQ("a", CodePointToUtf8(L'a', buffer));
-  EXPECT_STREQ("Z", CodePointToUtf8(L'Z', buffer));
-  EXPECT_STREQ("&", CodePointToUtf8(L'&', buffer));
-  EXPECT_STREQ("\x7F", CodePointToUtf8(L'\x7F', buffer));
+  EXPECT_EQ("a", CodePointToUtf8(L'a'));
+  EXPECT_EQ("Z", CodePointToUtf8(L'Z'));
+  EXPECT_EQ("&", CodePointToUtf8(L'&'));
+  EXPECT_EQ("\x7F", CodePointToUtf8(L'\x7F'));
 }
 
 // Tests that Unicode code-points that have 8 to 11 bits are encoded
 // as 110xxxxx 10xxxxxx.
 TEST(CodePointToUtf8Test, CanEncode8To11Bits) {
-  char buffer[32];
   // 000 1101 0011 => 110-00011 10-010011
-  EXPECT_STREQ("\xC3\x93", CodePointToUtf8(L'\xD3', buffer));
+  EXPECT_EQ("\xC3\x93", CodePointToUtf8(L'\xD3'));
 
   // 101 0111 0110 => 110-10101 10-110110
   // Some compilers (e.g., GCC on MinGW) cannot handle non-ASCII codepoints
   // in wide strings and wide chars. In order to accomodate them, we have to
   // introduce such character constants as integers.
-  EXPECT_STREQ("\xD5\xB6",
-               CodePointToUtf8(static_cast<wchar_t>(0x576), buffer));
+  EXPECT_EQ("\xD5\xB6",
+            CodePointToUtf8(static_cast<wchar_t>(0x576)));
 }
 
 // Tests that Unicode code-points that have 12 to 16 bits are encoded
 // as 1110xxxx 10xxxxxx 10xxxxxx.
 TEST(CodePointToUtf8Test, CanEncode12To16Bits) {
-  char buffer[32];
   // 0000 1000 1101 0011 => 1110-0000 10-100011 10-010011
-  EXPECT_STREQ("\xE0\xA3\x93",
-               CodePointToUtf8(static_cast<wchar_t>(0x8D3), buffer));
+  EXPECT_EQ("\xE0\xA3\x93",
+            CodePointToUtf8(static_cast<wchar_t>(0x8D3)));
 
   // 1100 0111 0100 1101 => 1110-1100 10-011101 10-001101
-  EXPECT_STREQ("\xEC\x9D\x8D",
-               CodePointToUtf8(static_cast<wchar_t>(0xC74D), buffer));
+  EXPECT_EQ("\xEC\x9D\x8D",
+            CodePointToUtf8(static_cast<wchar_t>(0xC74D)));
 }
 
 #if !GTEST_WIDE_STRING_USES_UTF16_
@@ -503,22 +499,19 @@ TEST(CodePointToUtf8Test, CanEncode12To16Bits) {
 // Tests that Unicode code-points that have 17 to 21 bits are encoded
 // as 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx.
 TEST(CodePointToUtf8Test, CanEncode17To21Bits) {
-  char buffer[32];
   // 0 0001 0000 1000 1101 0011 => 11110-000 10-010000 10-100011 10-010011
-  EXPECT_STREQ("\xF0\x90\xA3\x93", CodePointToUtf8(L'\x108D3', buffer));
+  EXPECT_EQ("\xF0\x90\xA3\x93", CodePointToUtf8(L'\x108D3'));
 
   // 0 0001 0000 0100 0000 0000 => 11110-000 10-010000 10-010000 10-000000
-  EXPECT_STREQ("\xF0\x90\x90\x80", CodePointToUtf8(L'\x10400', buffer));
+  EXPECT_EQ("\xF0\x90\x90\x80", CodePointToUtf8(L'\x10400'));
 
   // 1 0000 1000 0110 0011 0100 => 11110-100 10-001000 10-011000 10-110100
-  EXPECT_STREQ("\xF4\x88\x98\xB4", CodePointToUtf8(L'\x108634', buffer));
+  EXPECT_EQ("\xF4\x88\x98\xB4", CodePointToUtf8(L'\x108634'));
 }
 
 // Tests that encoding an invalid code-point generates the expected result.
 TEST(CodePointToUtf8Test, CanEncodeInvalidCodePoint) {
-  char buffer[32];
-  EXPECT_STREQ("(Invalid Unicode 0x1234ABCD)",
-               CodePointToUtf8(L'\x1234ABCD', buffer));
+  EXPECT_EQ("(Invalid Unicode 0x1234ABCD)", CodePointToUtf8(L'\x1234ABCD'));
 }
 
 #endif  // !GTEST_WIDE_STRING_USES_UTF16_
@@ -960,33 +953,6 @@ TEST(StringTest, CaseInsensitiveWideCStringEquals) {
   EXPECT_TRUE(String::CaseInsensitiveWideCStringEquals(L"FOOBAR", L"foobar"));
 }
 
-// Tests that String::Format() works.
-TEST(StringTest, FormatWorks) {
-  // Normal case: the format spec is valid, the arguments match the
-  // spec, and the result is < 4095 characters.
-  EXPECT_STREQ("Hello, 42", String::Format("%s, %d", "Hello", 42).c_str());
-
-  // Edge case: the result is 4095 characters.
-  char buffer[4096];
-  const size_t kSize = sizeof(buffer);
-  memset(buffer, 'a', kSize - 1);
-  buffer[kSize - 1] = '\0';
-  EXPECT_EQ(buffer, String::Format("%s", buffer));
-
-  // The result needs to be 4096 characters, exceeding Format()'s limit.
-  EXPECT_EQ("<formatting error or buffer exceeded>",
-            String::Format("x%s", buffer));
-
-#if GTEST_OS_LINUX && !GTEST_OS_LINUX_ANDROID
-  // On Linux, invalid format spec should lead to an error message.
-  // In other environment (e.g. MSVC on Windows), String::Format() may
-  // simply ignore a bad format spec, so this assertion is run on
-  // Linux only.
-  EXPECT_EQ("<formatting error or buffer exceeded>",
-            String::Format("%"));
-#endif
-}
-
 #if GTEST_OS_WINDOWS
 
 // Tests String::ShowWideCString().
@@ -3731,10 +3697,10 @@ TEST(HRESULTAssertionTest, EXPECT_HRESULT_FAILED) {
 
   EXPECT_NONFATAL_FAILURE(EXPECT_HRESULT_FAILED(OkHRESULTSuccess()),
     "Expected: (OkHRESULTSuccess()) fails.\n"
-    "  Actual: 0x00000000");
+    "  Actual: 0x0");
   EXPECT_NONFATAL_FAILURE(EXPECT_HRESULT_FAILED(FalseHRESULTSuccess()),
     "Expected: (FalseHRESULTSuccess()) fails.\n"
-    "  Actual: 0x00000001");
+    "  Actual: 0x1");
 }
 
 TEST(HRESULTAssertionTest, ASSERT_HRESULT_FAILED) {
@@ -3745,12 +3711,12 @@ TEST(HRESULTAssertionTest, ASSERT_HRESULT_FAILED) {
   // ICE's in C++Builder 2007 and 2009.
   EXPECT_FATAL_FAILURE(ASSERT_HRESULT_FAILED(OkHRESULTSuccess()),
     "Expected: (OkHRESULTSuccess()) fails.\n"
-    "  Actual: 0x00000000");
+    "  Actual: 0x0");
 # endif
 
   EXPECT_FATAL_FAILURE(ASSERT_HRESULT_FAILED(FalseHRESULTSuccess()),
     "Expected: (FalseHRESULTSuccess()) fails.\n"
-    "  Actual: 0x00000001");
+    "  Actual: 0x1");
 }
 
 // Tests that streaming to the HRESULT macros works.