Merge branch 'sync-piper' into sync-stage

# Conflicts:
#	java/core/src/test/java/com/google/protobuf/TextFormatTest.java

java/core/src/main/java/com/google/protobuf/GeneratedMessageLite.java

@@ -234,7 +234,7 @@ public abstract class GeneratedMessageLite<
    *       It doesn't use or modify any memoized value.
    *   <li>{@code GET_MEMOIZED_IS_INITIALIZED} returns the memoized {@code isInitialized} byte
    *       value.
-   *   <li>{@code SET_MEMOIZED_IS_INITIALIZED} sets the memoized {@code isInitilaized} byte value to
+   *   <li>{@code SET_MEMOIZED_IS_INITIALIZED} sets the memoized {@code isInitialized} byte value to
    *       1 if the first parameter is not null, or to 0 if the first parameter is null.
    *   <li>{@code NEW_BUILDER} returns a {@code BuilderType} instance.
    * </ul>
@@ -461,7 +461,7 @@ public abstract class GeneratedMessageLite<
         throws IOException {
       copyOnWrite();
       try {
-        // TODO(yilunchong): Try to make input with type CodedInpuStream.ArrayDecoder use
+        // TODO(yilunchong): Try to make input with type CodedInputStream.ArrayDecoder use
         // fast path.
         Protobuf.getInstance().schemaFor(instance).mergeFrom(
             instance, CodedInputStreamReader.forCodedInput(input), extensionRegistry);

java/core/src/test/java/com/google/protobuf/TextFormatTest.java

@@ -1419,10 +1419,10 @@ public class TextFormatTest extends TestCase {
             + "  value: -1\n"
             + "}\n";
     TestMap msg = TextFormat.parse(input, TestMap.class);
-    int val1 = msg.getInt32ToInt32Field().get(1);
+    int i1 = msg.getInt32ToInt32Field().get(1);
     TestMap msg2 = TextFormat.parse(msg.toString(), TestMap.class);
-    int val2 = msg2.getInt32ToInt32Field().get(1);
+    int i2 = msg2.getInt32ToInt32Field().get(1);
-    assertEquals(val1, val2);
+    assertEquals(i1, i2);
   }
 
   public void testMapShortForm() throws Exception {

python/google/protobuf/internal/enum_type_wrapper.py

@@ -48,32 +48,38 @@ class EnumTypeWrapper(object):
   def __init__(self, enum_type):
     """Inits EnumTypeWrapper with an EnumDescriptor."""
     self._enum_type = enum_type
-    self.DESCRIPTOR = enum_type
+    self.DESCRIPTOR = enum_type  # pylint: disable=invalid-name
 
-  def Name(self, number):
+  def Name(self, number):  # pylint: disable=invalid-name
     """Returns a string containing the name of an enum value."""
-    if number in self._enum_type.values_by_number:
+    try:
       return self._enum_type.values_by_number[number].name
+    except KeyError:
+      pass  # fall out to break exception chaining
 
     if not isinstance(number, six.integer_types):
-      raise TypeError('Enum value for %s must be an int, but got %r.' % (
+      raise TypeError(
-          self._enum_type.name, number))
+          'Enum value for {} must be an int, but got {} {!r}.'.format(
+              self._enum_type.name, type(number), number))
     else:
-      # %r here to handle the odd case when you pass in a boolean.
+      # repr here to handle the odd case when you pass in a boolean.
-      raise ValueError('Enum %s has no name defined for value %r' % (
+      raise ValueError('Enum {} has no name defined for value {!r}'.format(
           self._enum_type.name, number))
 
-  def Value(self, name):
+  def Value(self, name):  # pylint: disable=invalid-name
     """Returns the value corresponding to the given enum name."""
-    if name in self._enum_type.values_by_name:
+    try:
       return self._enum_type.values_by_name[name].number
-    raise ValueError('Enum %s has no value defined for name %s' % (
+    except KeyError:
+      pass  # fall out to break exception chaining
+    raise ValueError('Enum {} has no value defined for name {!r}'.format(
         self._enum_type.name, name))
 
   def keys(self):
     """Return a list of the string names in the enum.
 
-    These are returned in the order they were defined in the .proto file.
+    Returns:
+      A list of strs, in the order they were defined in the .proto file.
     """
 
     return [value_descriptor.name
@@ -82,7 +88,8 @@ class EnumTypeWrapper(object):
   def values(self):
     """Return a list of the integer values in the enum.
 
-    These are returned in the order they were defined in the .proto file.
+    Returns:
+      A list of ints, in the order they were defined in the .proto file.
     """
 
     return [value_descriptor.number
@@ -91,13 +98,18 @@ class EnumTypeWrapper(object):
   def items(self):
     """Return a list of the (name, value) pairs of the enum.
 
-    These are returned in the order they were defined in the .proto file.
+    Returns:
+      A list of (str, int) pairs, in the order they were defined
+      in the .proto file.
     """
     return [(value_descriptor.name, value_descriptor.number)
             for value_descriptor in self._enum_type.values]
 
   def __getattr__(self, name):
     """Returns the value corresponding to the given enum name."""
-    if name in self._enum_type.values_by_name:
+    try:
       return self._enum_type.values_by_name[name].number
-    raise AttributeError
+    except KeyError:
+      pass  # fall out to break exception chaining
+    raise AttributeError('Enum {} has no value defined for name {!r}'.format(
+        self._enum_type.name, name))

python/google/protobuf/internal/json_format_test.py

@@ -1157,6 +1157,19 @@ class JsonFormatTest(JsonFormatBase):
         'Failed to parse any_value field: Can not find message descriptor by'
         ' type_url: type.googleapis.com/proto3.MessageType..')
 
+  def testParseDictUnknownValueType(self):
+    class UnknownClass(object):
+
+      def __str__(self):
+        return 'v'
+    message = json_format_proto3_pb2.TestValue()
+    self.assertRaisesRegexp(
+        json_format.ParseError,
+        r"Value v has unexpected type <class '.*\.UnknownClass'>.",
+        json_format.ParseDict,
+        {'value': UnknownClass()},
+        message)
+
   def testMessageToDict(self):
     message = json_format_proto3_pb2.TestMessage()
     message.int32_value = 12345

python/google/protobuf/json_format.py

@@ -647,7 +647,8 @@ class _Parser(object):
     elif isinstance(value, _INT_OR_FLOAT):
       message.number_value = value
     else:
-      raise ParseError('Unexpected type for Value message.')
+      raise ParseError('Value {0} has unexpected type {1}.'.format(
+          value, type(value)))
 
   def _ConvertListValueMessage(self, value, message):
     """Convert a JSON representation into ListValue message."""

src/google/protobuf/compiler/cpp/cpp_enum.cc

@@ -180,14 +180,17 @@ void EnumGenerator::GenerateDefinition(io::Printer* printer) {
   if (HasDescriptorMethods(descriptor_->file(), options_)) {
     format(
         "inline bool $classname$_Parse(\n"
-        "    const std::string& name, $classname$* value) {\n"
+        "    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, $classname$* "
+        "value) "
+        "{\n"
         "  return ::$proto_ns$::internal::ParseNamedEnum<$classname$>(\n"
         "    $classname$_descriptor(), name, value);\n"
         "}\n");
   } else {
     format(
         "bool $classname$_Parse(\n"
-        "    const std::string& name, $classname$* value);\n");
+        "    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, $classname$* "
+        "value);\n");
   }
 }
 
@@ -253,7 +256,8 @@ void EnumGenerator::GenerateSymbolImports(io::Printer* printer) const {
       "  return $classname$_Name(enum_t_value);\n"
       "}\n");
   format(
-      "static inline bool $nested_name$_Parse(const std::string& name,\n"
+      "static inline bool "
+      "$nested_name$_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,\n"
       "    $resolved_name$* value) {\n"
       "  return $classname$_Parse(name, value);\n"
       "}\n");
@@ -383,7 +387,9 @@ void EnumGenerator::GenerateMethods(int idx, io::Printer* printer) {
         CountUniqueValues(descriptor_));
     format(
         "bool $classname$_Parse(\n"
-        "    const std::string& name, $classname$* value) {\n"
+        "    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, $classname$* "
+        "value) "
+        "{\n"
         "  int int_value;\n"
         "  bool success = ::$proto_ns$::internal::LookUpEnumValue(\n"
         "      $classname$_entries, $1$, name, &int_value);\n"

src/google/protobuf/compiler/java/java_helpers.cc

@@ -75,8 +75,8 @@ const char* kForbiddenWordList[] = {
     "class",
 };
 
-const std::unordered_set<string>* kReservedNames =
+const std::unordered_set<std::string>* kReservedNames =
-    new std::unordered_set<string>({
+    new std::unordered_set<std::string>({
         "abstract",   "assert",       "boolean",   "break",      "byte",
         "case",       "catch",        "char",      "class",      "const",
         "continue",   "default",      "do",        "double",     "else",

src/google/protobuf/compiler/java/java_name_resolver.cc

@@ -91,7 +91,7 @@ std::string ClassNameWithoutPackage(const ServiceDescriptor* descriptor,
 }
 
 // Return true if a and b are equals (case insensitive).
-NameEquality CheckNameEquality(const string& a, const string& b) {
+NameEquality CheckNameEquality(const std::string& a, const std::string& b) {
   if (ToUpper(a) == ToUpper(b)) {
     if (a == b) {
       return NameEquality::EXACT_EQUAL;

src/google/protobuf/compiler/plugin.pb.h

@@ -106,7 +106,7 @@ inline const std::string& CodeGeneratorResponse_Feature_Name(T enum_t_value) {
     CodeGeneratorResponse_Feature_descriptor(), enum_t_value);
 }
 inline bool CodeGeneratorResponse_Feature_Parse(
-    const std::string& name, CodeGeneratorResponse_Feature* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, CodeGeneratorResponse_Feature* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<CodeGeneratorResponse_Feature>(
     CodeGeneratorResponse_Feature_descriptor(), name, value);
 }
@@ -924,7 +924,7 @@ class PROTOC_EXPORT CodeGeneratorResponse PROTOBUF_FINAL :
       "Incorrect type passed to function Feature_Name.");
     return CodeGeneratorResponse_Feature_Name(enum_t_value);
   }
-  static inline bool Feature_Parse(const std::string& name,
+  static inline bool Feature_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       Feature* value) {
     return CodeGeneratorResponse_Feature_Parse(name, value);
   }

src/google/protobuf/compiler/python/python_generator.cc

@@ -125,7 +125,7 @@ bool ContainsPythonKeyword(const std::string& module_name) {
   return false;
 }
 
-inline bool IsPythonKeyword(const string& name) {
+inline bool IsPythonKeyword(const std::string& name) {
   return (std::find(kKeywords, kKeywordsEnd, name) != kKeywordsEnd);
 }
 

src/google/protobuf/descriptor.cc

@@ -383,19 +383,8 @@ class PrefixRemover {
 // hash-maps for each object.
 //
 // The keys to these hash-maps are (parent, name) or (parent, number) pairs.
-//
-// TODO(kenton):  Use StringPiece rather than const char* in keys?  It would
-//   be a lot cleaner but we'd just have to convert it back to const char*
-//   for the open source release.
 
-typedef std::pair<const void*, const char*> PointerStringPair;
+typedef std::pair<const void*, StringPiece> PointerStringPair;
-
-struct PointerStringPairEqual {
-  inline bool operator()(const PointerStringPair& a,
-                         const PointerStringPair& b) const {
-    return a.first == b.first && strcmp(a.second, b.second) == 0;
-  }
-};
 
 typedef std::pair<const Descriptor*, int> DescriptorIntPair;
 typedef std::pair<const EnumDescriptor*, int> EnumIntPair;
@@ -419,16 +408,16 @@ struct PointerIntegerPairHash {
   static const size_t min_buckets = 8;
 #endif
   inline bool operator()(const PairType& a, const PairType& b) const {
-    return a.first < b.first || (a.first == b.first && a.second < b.second);
+    return a < b;
   }
 };
 
 struct PointerStringPairHash {
   size_t operator()(const PointerStringPair& p) const {
     static const size_t prime = 16777619;
-    hash<const char*> cstring_hash;
+    hash<StringPiece> string_hash;
     return reinterpret_cast<size_t>(p.first) * prime ^
-           static_cast<size_t>(cstring_hash(p.second));
+           static_cast<size_t>(string_hash(p.second));
   }
 
 #ifdef _MSC_VER
@@ -438,9 +427,7 @@ struct PointerStringPairHash {
 #endif
   inline bool operator()(const PointerStringPair& a,
                          const PointerStringPair& b) const {
-    if (a.first < b.first) return true;
+    return a < b;
-    if (a.first > b.first) return false;
-    return strcmp(a.second, b.second) < 0;
   }
 };
 
@@ -450,8 +437,7 @@ const Symbol kNullSymbol;
 typedef HASH_MAP<const char*, Symbol, HASH_FXN<const char*>, streq>
     SymbolsByNameMap;
 
-typedef HASH_MAP<PointerStringPair, Symbol, PointerStringPairHash,
+typedef HASH_MAP<PointerStringPair, Symbol, PointerStringPairHash>
-                 PointerStringPairEqual>
     SymbolsByParentMap;
 
 typedef HASH_MAP<const char*, const FileDescriptor*, HASH_FXN<const char*>,
@@ -459,7 +445,7 @@ typedef HASH_MAP<const char*, const FileDescriptor*, HASH_FXN<const char*>,
     FilesByNameMap;
 
 typedef HASH_MAP<PointerStringPair, const FieldDescriptor*,
-                 PointerStringPairHash, PointerStringPairEqual>
+                 PointerStringPairHash>
     FieldsByNameMap;
 
 typedef HASH_MAP<DescriptorIntPair, const FieldDescriptor*,
@@ -720,9 +706,9 @@ class FileDescriptorTables {
   // Find symbols.  These return a null Symbol (symbol.IsNull() is true)
   // if not found.
   inline Symbol FindNestedSymbol(const void* parent,
-                                 const std::string& name) const;
+                                 StringPiece name) const;
   inline Symbol FindNestedSymbolOfType(const void* parent,
-                                       const std::string& name,
+                                       StringPiece name,
                                        const Symbol::Type type) const;
 
   // These return nullptr if not found.
@@ -908,9 +894,9 @@ inline Symbol DescriptorPool::Tables::FindSymbol(const std::string& key) const {
 }
 
 inline Symbol FileDescriptorTables::FindNestedSymbol(
-    const void* parent, const std::string& name) const {
+    const void* parent, StringPiece name) const {
-  const Symbol* result = FindOrNull(
+  const Symbol* result =
-      symbols_by_parent_, PointerStringPair(parent, name.c_str()));
+      FindOrNull(symbols_by_parent_, PointerStringPair(parent, name));
   if (result == nullptr) {
     return kNullSymbol;
   } else {
@@ -919,8 +905,7 @@ inline Symbol FileDescriptorTables::FindNestedSymbol(
 }
 
 inline Symbol FileDescriptorTables::FindNestedSymbolOfType(
-    const void* parent, const std::string& name,
+    const void* parent, StringPiece name, const Symbol::Type type) const {
-    const Symbol::Type type) const {
   Symbol result = FindNestedSymbol(parent, name);
   if (result.type != type) return kNullSymbol;
   return result;
@@ -1737,7 +1722,7 @@ const FieldDescriptor* Descriptor::map_value() const {
 }
 
 const EnumValueDescriptor* EnumDescriptor::FindValueByName(
-    const std::string& key) const {
+    ConstStringParam key) const {
   Symbol result =
       file()->tables_->FindNestedSymbolOfType(this, key, Symbol::ENUM_VALUE);
   if (!result.IsNull()) {

src/google/protobuf/descriptor.h

@@ -63,6 +63,7 @@
 #include <google/protobuf/stubs/common.h>
 #include <google/protobuf/stubs/mutex.h>
 #include <google/protobuf/stubs/once.h>
+#include <google/protobuf/port.h>
 #include <google/protobuf/port_def.inc>
 
 // TYPE_BOOL is defined in the MacOS's ConditionalMacros.h.
@@ -1029,7 +1030,7 @@ class PROTOBUF_EXPORT EnumDescriptor {
   const EnumValueDescriptor* value(int index) const;
 
   // Looks up a value by name.  Returns nullptr if no such value exists.
-  const EnumValueDescriptor* FindValueByName(const std::string& name) const;
+  const EnumValueDescriptor* FindValueByName(ConstStringParam name) const;
   // Looks up a value by number.  Returns nullptr if no such value exists.  If
   // multiple values have this number, the first one defined is returned.
   const EnumValueDescriptor* FindValueByNumber(int number) const;

src/google/protobuf/descriptor.pb.h

@@ -204,7 +204,7 @@ inline const std::string& FieldDescriptorProto_Type_Name(T enum_t_value) {
     FieldDescriptorProto_Type_descriptor(), enum_t_value);
 }
 inline bool FieldDescriptorProto_Type_Parse(
-    const std::string& name, FieldDescriptorProto_Type* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, FieldDescriptorProto_Type* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<FieldDescriptorProto_Type>(
     FieldDescriptorProto_Type_descriptor(), name, value);
 }
@@ -228,7 +228,7 @@ inline const std::string& FieldDescriptorProto_Label_Name(T enum_t_value) {
     FieldDescriptorProto_Label_descriptor(), enum_t_value);
 }
 inline bool FieldDescriptorProto_Label_Parse(
-    const std::string& name, FieldDescriptorProto_Label* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, FieldDescriptorProto_Label* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<FieldDescriptorProto_Label>(
     FieldDescriptorProto_Label_descriptor(), name, value);
 }
@@ -252,7 +252,7 @@ inline const std::string& FileOptions_OptimizeMode_Name(T enum_t_value) {
     FileOptions_OptimizeMode_descriptor(), enum_t_value);
 }
 inline bool FileOptions_OptimizeMode_Parse(
-    const std::string& name, FileOptions_OptimizeMode* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, FileOptions_OptimizeMode* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<FileOptions_OptimizeMode>(
     FileOptions_OptimizeMode_descriptor(), name, value);
 }
@@ -276,7 +276,7 @@ inline const std::string& FieldOptions_CType_Name(T enum_t_value) {
     FieldOptions_CType_descriptor(), enum_t_value);
 }
 inline bool FieldOptions_CType_Parse(
-    const std::string& name, FieldOptions_CType* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, FieldOptions_CType* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<FieldOptions_CType>(
     FieldOptions_CType_descriptor(), name, value);
 }
@@ -300,7 +300,7 @@ inline const std::string& FieldOptions_JSType_Name(T enum_t_value) {
     FieldOptions_JSType_descriptor(), enum_t_value);
 }
 inline bool FieldOptions_JSType_Parse(
-    const std::string& name, FieldOptions_JSType* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, FieldOptions_JSType* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<FieldOptions_JSType>(
     FieldOptions_JSType_descriptor(), name, value);
 }
@@ -324,7 +324,7 @@ inline const std::string& MethodOptions_IdempotencyLevel_Name(T enum_t_value) {
     MethodOptions_IdempotencyLevel_descriptor(), enum_t_value);
 }
 inline bool MethodOptions_IdempotencyLevel_Parse(
-    const std::string& name, MethodOptions_IdempotencyLevel* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, MethodOptions_IdempotencyLevel* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<MethodOptions_IdempotencyLevel>(
     MethodOptions_IdempotencyLevel_descriptor(), name, value);
 }
@@ -1936,7 +1936,7 @@ class PROTOBUF_EXPORT FieldDescriptorProto PROTOBUF_FINAL :
       "Incorrect type passed to function Type_Name.");
     return FieldDescriptorProto_Type_Name(enum_t_value);
   }
-  static inline bool Type_Parse(const std::string& name,
+  static inline bool Type_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       Type* value) {
     return FieldDescriptorProto_Type_Parse(name, value);
   }
@@ -1968,7 +1968,7 @@ class PROTOBUF_EXPORT FieldDescriptorProto PROTOBUF_FINAL :
       "Incorrect type passed to function Label_Name.");
     return FieldDescriptorProto_Label_Name(enum_t_value);
   }
-  static inline bool Label_Parse(const std::string& name,
+  static inline bool Label_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       Label* value) {
     return FieldDescriptorProto_Label_Parse(name, value);
   }
@@ -3668,7 +3668,7 @@ class PROTOBUF_EXPORT FileOptions PROTOBUF_FINAL :
       "Incorrect type passed to function OptimizeMode_Name.");
     return FileOptions_OptimizeMode_Name(enum_t_value);
   }
-  static inline bool OptimizeMode_Parse(const std::string& name,
+  static inline bool OptimizeMode_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       OptimizeMode* value) {
     return FileOptions_OptimizeMode_Parse(name, value);
   }
@@ -4534,7 +4534,7 @@ class PROTOBUF_EXPORT FieldOptions PROTOBUF_FINAL :
       "Incorrect type passed to function CType_Name.");
     return FieldOptions_CType_Name(enum_t_value);
   }
-  static inline bool CType_Parse(const std::string& name,
+  static inline bool CType_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       CType* value) {
     return FieldOptions_CType_Parse(name, value);
   }
@@ -4566,7 +4566,7 @@ class PROTOBUF_EXPORT FieldOptions PROTOBUF_FINAL :
       "Incorrect type passed to function JSType_Name.");
     return FieldOptions_JSType_Name(enum_t_value);
   }
-  static inline bool JSType_Parse(const std::string& name,
+  static inline bool JSType_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       JSType* value) {
     return FieldOptions_JSType_Parse(name, value);
   }
@@ -5532,7 +5532,7 @@ class PROTOBUF_EXPORT MethodOptions PROTOBUF_FINAL :
       "Incorrect type passed to function IdempotencyLevel_Name.");
     return MethodOptions_IdempotencyLevel_Name(enum_t_value);
   }
-  static inline bool IdempotencyLevel_Parse(const std::string& name,
+  static inline bool IdempotencyLevel_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       IdempotencyLevel* value) {
     return MethodOptions_IdempotencyLevel_Parse(name, value);
   }

src/google/protobuf/descriptor_database.cc

@@ -41,6 +41,7 @@
 #include <google/protobuf/stubs/map_util.h>
 #include <google/protobuf/stubs/stl_util.h>
 
+
 namespace google {
 namespace protobuf {
 
@@ -389,11 +390,14 @@ bool SimpleDescriptorDatabase::MaybeCopy(const FileDescriptorProto* file,
 // -------------------------------------------------------------------
 
 class EncodedDescriptorDatabase::DescriptorIndex {
+  using String = std::string;
+
  public:
   using Value = std::pair<const void*, int>;
   // Helpers to recursively add particular descriptors and all their contents
   // to the index.
-  bool AddFile(const FileDescriptorProto& file, Value value);
+  template <typename FileProto>
+  bool AddFile(const FileProto& file, Value value);
 
   Value FindFile(StringPiece filename);
   Value FindSymbol(StringPiece name);
@@ -406,11 +410,15 @@ class EncodedDescriptorDatabase::DescriptorIndex {
  private:
   friend class EncodedDescriptorDatabase;
 
-  bool AddSymbol(StringPiece name, Value value);
+  bool AddSymbol(StringPiece package, StringPiece symbol,
+                 Value value);
+
+  template <typename DescProto>
   bool AddNestedExtensions(StringPiece filename,
-                           const DescriptorProto& message_type, Value value);
+                           const DescProto& message_type, Value value);
-  bool AddExtension(StringPiece filename,
+  template <typename FieldProto>
-                    const FieldDescriptorProto& field, Value value);
+  bool AddExtension(StringPiece filename, const FieldProto& field,
+                    Value value);
 
   // All the maps below have two representations:
   //  - a std::set<> where we insert initially.
@@ -421,27 +429,72 @@ class EncodedDescriptorDatabase::DescriptorIndex {
 
   void EnsureFlat();
 
-  struct Entry {
+  struct FileEntry {
-    std::string name;
+    String name;
     Value data;
   };
-  struct Compare {
+  struct FileCompare {
-    bool operator()(const Entry& a, const Entry& b) const {
+    bool operator()(const FileEntry& a, const FileEntry& b) const {
       return a.name < b.name;
     }
-    bool operator()(const Entry& a, StringPiece b) const {
+    bool operator()(const FileEntry& a, StringPiece b) const {
       return a.name < b;
     }
-    bool operator()(StringPiece a, const Entry& b) const {
+    bool operator()(StringPiece a, const FileEntry& b) const {
       return a < b.name;
     }
   };
-  std::set<Entry, Compare> by_name_;
+  std::set<FileEntry, FileCompare> by_name_;
-  std::vector<Entry> by_name_flat_;
+  std::vector<FileEntry> by_name_flat_;
-  std::set<Entry, Compare> by_symbol_;
+
-  std::vector<Entry> by_symbol_flat_;
+  struct SymbolEntry {
+    String package;
+    String symbol;
+    Value data;
+
+    std::string AsString() const {
+      return StrCat(package, package.empty() ? "" : ".", symbol);
+    }
+  };
+
+  struct SymbolCompare {
+    static std::string AsString(const SymbolEntry& entry) {
+      return entry.AsString();
+    }
+    static StringPiece AsString(StringPiece str) { return str; }
+
+    static std::pair<StringPiece, StringPiece> GetParts(
+        const SymbolEntry& entry) {
+      if (entry.package.empty()) return {entry.symbol, StringPiece{}};
+      return {entry.package, entry.symbol};
+    }
+    static std::pair<StringPiece, StringPiece> GetParts(
+        StringPiece str) {
+      return {str, {}};
+    }
+
+    template <typename T, typename U>
+    bool operator()(const T& lhs, const U& rhs) const {
+      auto lhs_parts = GetParts(lhs);
+      auto rhs_parts = GetParts(rhs);
+
+      // Fast path to avoid making the whole string for common cases.
+      if (int res =
+              lhs_parts.first.substr(0, rhs_parts.first.size())
+                  .compare(rhs_parts.first.substr(0, lhs_parts.first.size()))) {
+        // If the packages already differ, exit early.
+        return res < 0;
+      } else if (lhs_parts.first.size() == rhs_parts.first.size()) {
+        return lhs_parts.second < rhs_parts.second;
+      }
+      return AsString(lhs) < AsString(rhs);
+    }
+  };
+  std::set<SymbolEntry, SymbolCompare> by_symbol_;
+  std::vector<SymbolEntry> by_symbol_flat_;
+
   struct ExtensionEntry {
-    std::string extendee;
+    String extendee;
     int extension_number;
     Value data;
   };
@@ -535,34 +588,30 @@ bool EncodedDescriptorDatabase::FindAllExtensionNumbers(
   return index_->FindAllExtensionNumbers(extendee_type, output);
 }
 
-bool EncodedDescriptorDatabase::DescriptorIndex::AddFile(
+template <typename FileProto>
-    const FileDescriptorProto& file, Value value) {
+bool EncodedDescriptorDatabase::DescriptorIndex::AddFile(const FileProto& file,
-  if (!InsertIfNotPresent(&by_name_, Entry{file.name(), value}) ||
+                                                         Value value) {
+  if (!InsertIfNotPresent(&by_name_, FileEntry{file.name(), value}) ||
       std::binary_search(by_name_flat_.begin(), by_name_flat_.end(),
                          file.name(), by_name_.key_comp())) {
     GOOGLE_LOG(ERROR) << "File already exists in database: " << file.name();
     return false;
   }
 
-  // We must be careful here -- calling file.package() if file.has_package() is
+  StringPiece package = file.package();
-  // false could access an uninitialized static-storage variable if we are being
-  // run at startup time.
-  std::string path = file.has_package() ? file.package() : std::string();
-  if (!path.empty()) path += '.';
-
   for (const auto& message_type : file.message_type()) {
-    if (!AddSymbol(path + message_type.name(), value)) return false;
+    if (!AddSymbol(package, message_type.name(), value)) return false;
     if (!AddNestedExtensions(file.name(), message_type, value)) return false;
   }
   for (const auto& enum_type : file.enum_type()) {
-    if (!AddSymbol(path + enum_type.name(), value)) return false;
+    if (!AddSymbol(package, enum_type.name(), value)) return false;
   }
   for (const auto& extension : file.extension()) {
-    if (!AddSymbol(path + extension.name(), value)) return false;
+    if (!AddSymbol(package, extension.name(), value)) return false;
     if (!AddExtension(file.name(), extension, value)) return false;
   }
   for (const auto& service : file.service()) {
-    if (!AddSymbol(path + service.name(), value)) return false;
+    if (!AddSymbol(package, service.name(), value)) return false;
   }
 
   return true;
@@ -572,10 +621,10 @@ template <typename Iter, typename Iter2>
 static bool CheckForMutualSubsymbols(StringPiece symbol_name, Iter* iter,
                                      Iter2 end) {
   if (*iter != end) {
-    if (IsSubSymbol((*iter)->name, symbol_name)) {
+    if (IsSubSymbol((*iter)->AsString(), symbol_name)) {
       GOOGLE_LOG(ERROR) << "Symbol name \"" << symbol_name
-                 << "\" conflicts with the existing symbol \"" << (*iter)->name
+                 << "\" conflicts with the existing symbol \""
-                 << "\".";
+                 << (*iter)->AsString() << "\".";
       return false;
     }
 
@@ -586,10 +635,10 @@ static bool CheckForMutualSubsymbols(StringPiece symbol_name, Iter* iter,
     // to increment it.
     ++*iter;
 
-    if (*iter != end && IsSubSymbol(symbol_name, (*iter)->name)) {
+    if (*iter != end && IsSubSymbol(symbol_name, (*iter)->AsString())) {
       GOOGLE_LOG(ERROR) << "Symbol name \"" << symbol_name
-                 << "\" conflicts with the existing symbol \"" << (*iter)->name
+                 << "\" conflicts with the existing symbol \""
-                 << "\".";
+                 << (*iter)->AsString() << "\".";
       return false;
     }
   }
@@ -597,28 +646,30 @@ static bool CheckForMutualSubsymbols(StringPiece symbol_name, Iter* iter,
 }
 
 bool EncodedDescriptorDatabase::DescriptorIndex::AddSymbol(
-    StringPiece name, Value value) {
+    StringPiece package, StringPiece symbol, Value value) {
+  SymbolEntry entry = {String(package), String(symbol), value};
+  std::string entry_as_string = entry.AsString();
+
   // We need to make sure not to violate our map invariant.
 
   // If the symbol name is invalid it could break our lookup algorithm (which
   // relies on the fact that '.' sorts before all other characters that are
   // valid in symbol names).
-  if (!ValidateSymbolName(name)) {
+  if (!ValidateSymbolName(package) || !ValidateSymbolName(symbol)) {
-    GOOGLE_LOG(ERROR) << "Invalid symbol name: " << name;
+    GOOGLE_LOG(ERROR) << "Invalid symbol name: " << entry_as_string;
     return false;
   }
 
-  Entry entry = {std::string(name), value};
-
   auto iter = FindLastLessOrEqual(&by_symbol_, entry);
-  if (!CheckForMutualSubsymbols(name, &iter, by_symbol_.end())) {
+  if (!CheckForMutualSubsymbols(entry_as_string, &iter, by_symbol_.end())) {
     return false;
   }
 
   // Same, but on by_symbol_flat_
   auto flat_iter =
-      FindLastLessOrEqual(&by_symbol_flat_, name, by_symbol_.key_comp());
+      FindLastLessOrEqual(&by_symbol_flat_, entry, by_symbol_.key_comp());
-  if (!CheckForMutualSubsymbols(name, &flat_iter, by_symbol_flat_.end())) {
+  if (!CheckForMutualSubsymbols(entry_as_string, &flat_iter,
+                                by_symbol_flat_.end())) {
     return false;
   }
 
@@ -626,14 +677,14 @@ bool EncodedDescriptorDatabase::DescriptorIndex::AddSymbol(
 
   // Insert the new symbol using the iterator as a hint, the new entry will
   // appear immediately before the one the iterator is pointing at.
-  by_symbol_.insert(iter, std::move(entry));
+  by_symbol_.insert(iter, entry);
 
   return true;
 }
 
+template <typename DescProto>
 bool EncodedDescriptorDatabase::DescriptorIndex::AddNestedExtensions(
-    StringPiece filename, const DescriptorProto& message_type,
+    StringPiece filename, const DescProto& message_type, Value value) {
-    Value value) {
   for (const auto& nested_type : message_type.nested_type()) {
     if (!AddNestedExtensions(filename, nested_type, value)) return false;
   }
@@ -643,9 +694,9 @@ bool EncodedDescriptorDatabase::DescriptorIndex::AddNestedExtensions(
   return true;
 }
 
+template <typename FieldProto>
 bool EncodedDescriptorDatabase::DescriptorIndex::AddExtension(
-    StringPiece filename, const FieldDescriptorProto& field,
+    StringPiece filename, const FieldProto& field, Value value) {
-    Value value) {
   if (!field.extendee().empty() && field.extendee()[0] == '.') {
     // The extension is fully-qualified.  We can use it as a lookup key in
     // the by_symbol_ table.
@@ -682,7 +733,7 @@ EncodedDescriptorDatabase::DescriptorIndex::FindSymbolOnlyFlat(
   auto iter =
       FindLastLessOrEqual(&by_symbol_flat_, name, by_symbol_.key_comp());
 
-  return iter != by_symbol_flat_.end() && IsSubSymbol(iter->name, name)
+  return iter != by_symbol_flat_.end() && IsSubSymbol(iter->AsString(), name)
              ? iter->data
              : Value();
 }
@@ -740,11 +791,11 @@ void EncodedDescriptorDatabase::DescriptorIndex::FindAllFileNames(
   output->resize(by_name_.size() + by_name_flat_.size());
   int i = 0;
   for (const auto& entry : by_name_) {
-    (*output)[i] = entry.name;
+    (*output)[i] = std::string(entry.name);
     i++;
   }
   for (const auto& entry : by_name_flat_) {
-    (*output)[i] = entry.name;
+    (*output)[i] = std::string(entry.name);
     i++;
   }
 }

src/google/protobuf/descriptor_database_unittest.cc

@@ -547,7 +547,7 @@ TEST(SimpleDescriptorDatabaseExtraTest, FindAllPackageNames) {
   db.Add(f);
   db.Add(b);
 
-  std::vector<string> packages;
+  std::vector<std::string> packages;
   EXPECT_TRUE(db.FindAllPackageNames(&packages));
   EXPECT_THAT(packages, ::testing::UnorderedElementsAre("foo", ""));
 }
@@ -567,7 +567,7 @@ TEST(SimpleDescriptorDatabaseExtraTest, FindAllMessageNames) {
   db.Add(f);
   db.Add(b);
 
-  std::vector<string> messages;
+  std::vector<std::string> messages;
   EXPECT_TRUE(db.FindAllMessageNames(&messages));
   EXPECT_THAT(messages, ::testing::UnorderedElementsAre("foo.Foo", "Bar"));
 }

src/google/protobuf/dynamic_message.cc

@@ -336,26 +336,24 @@ class DynamicMessage : public Message {
   }
 
   const TypeInfo* type_info_;
-  Arena* const arena_;
   mutable std::atomic<int> cached_byte_size_;
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(DynamicMessage);
 };
 
 DynamicMessage::DynamicMessage(const TypeInfo* type_info)
-    : type_info_(type_info), arena_(NULL), cached_byte_size_(0) {
+    : type_info_(type_info), cached_byte_size_(0) {
   SharedCtor(true);
 }
 
 DynamicMessage::DynamicMessage(const TypeInfo* type_info, Arena* arena)
     : Message(arena),
       type_info_(type_info),
-      arena_(arena),
       cached_byte_size_(0) {
   SharedCtor(true);
 }
 
 DynamicMessage::DynamicMessage(TypeInfo* type_info, bool lock_factory)
-    : type_info_(type_info), arena_(NULL), cached_byte_size_(0) {
+    : type_info_(type_info), cached_byte_size_(0) {
   // The prototype in type_info has to be set before creating the prototype
   // instance on memory. e.g., message Foo { map<int32, Foo> a = 1; }. When
   // creating prototype for Foo, prototype of the map entry will also be
@@ -386,7 +384,8 @@ void DynamicMessage::SharedCtor(bool lock_factory) {
   }
 
   if (type_info_->extensions_offset != -1) {
-    new (OffsetToPointer(type_info_->extensions_offset)) ExtensionSet(arena_);
+    new (OffsetToPointer(type_info_->extensions_offset))
+        ExtensionSet(GetArena());
   }
   for (int i = 0; i < descriptor->field_count(); i++) {
     const FieldDescriptor* field = descriptor->field(i);
@@ -400,7 +399,7 @@ void DynamicMessage::SharedCtor(bool lock_factory) {
     if (!field->is_repeated()) {                           \
       new (field_ptr) TYPE(field->default_value_##TYPE()); \
     } else {                                               \
-      new (field_ptr) RepeatedField<TYPE>(arena_);         \
+      new (field_ptr) RepeatedField<TYPE>(GetArena());     \
     }                                                      \
     break;
 
@@ -417,7 +416,7 @@ void DynamicMessage::SharedCtor(bool lock_factory) {
         if (!field->is_repeated()) {
           new (field_ptr) int(field->default_value_enum()->number());
         } else {
-          new (field_ptr) RepeatedField<int>(arena_);
+          new (field_ptr) RepeatedField<int>(GetArena());
         }
         break;
 
@@ -438,7 +437,7 @@ void DynamicMessage::SharedCtor(bool lock_factory) {
               ArenaStringPtr* asp = new (field_ptr) ArenaStringPtr();
               asp->UnsafeSetDefault(default_value);
             } else {
-              new (field_ptr) RepeatedPtrField<std::string>(arena_);
+              new (field_ptr) RepeatedPtrField<std::string>(GetArena());
             }
             break;
         }
@@ -453,20 +452,20 @@ void DynamicMessage::SharedCtor(bool lock_factory) {
             // when the constructor is called inside GetPrototype(), in which
             // case we have already locked the factory.
             if (lock_factory) {
-              if (arena_ != NULL) {
+              if (GetArena() != nullptr) {
                 new (field_ptr) DynamicMapField(
                     type_info_->factory->GetPrototype(field->message_type()),
-                    arena_);
+                    GetArena());
               } else {
                 new (field_ptr) DynamicMapField(
                     type_info_->factory->GetPrototype(field->message_type()));
               }
             } else {
-              if (arena_ != NULL) {
+              if (GetArena() != nullptr) {
                 new (field_ptr)
                     DynamicMapField(type_info_->factory->GetPrototypeNoLock(
                                         field->message_type()),
-                                    arena_);
+                                    GetArena());
               } else {
                 new (field_ptr)
                     DynamicMapField(type_info_->factory->GetPrototypeNoLock(
@@ -474,7 +473,7 @@ void DynamicMessage::SharedCtor(bool lock_factory) {
               }
             }
           } else {
-            new (field_ptr) RepeatedPtrField<Message>(arena_);
+            new (field_ptr) RepeatedPtrField<Message>(GetArena());
           }
         }
         break;

src/google/protobuf/dynamic_message_unittest.cc

@@ -252,7 +252,7 @@ TEST_P(DynamicMessageTest, Oneof) {
 }
 
 TEST_P(DynamicMessageTest, SpaceUsed) {
-  // Test that SpaceUsed() works properly
+  // Test that SpaceUsedLong() works properly
 
   // Since we share the implementation with generated messages, we don't need
   // to test very much here.  Just make sure it appears to be working.
@@ -261,10 +261,10 @@ TEST_P(DynamicMessageTest, SpaceUsed) {
   Message* message = prototype_->New(GetParam() ? &arena : NULL);
   TestUtil::ReflectionTester reflection_tester(descriptor_);
 
-  int initial_space_used = message->SpaceUsed();
+  size_t initial_space_used = message->SpaceUsedLong();
 
   reflection_tester.SetAllFieldsViaReflection(message);
-  EXPECT_LT(initial_space_used, message->SpaceUsed());
+  EXPECT_LT(initial_space_used, message->SpaceUsedLong());
 
   if (!GetParam()) {
     delete message;

src/google/protobuf/extension_set_unittest.cc

@@ -514,7 +514,7 @@ TEST(ExtensionSetTest, SerializationToArray) {
   unittest::TestAllExtensions source;
   unittest::TestAllTypes destination;
   TestUtil::SetAllExtensions(&source);
-  int size = source.ByteSize();
+  size_t size = source.ByteSizeLong();
   std::string data;
   data.resize(size);
   uint8* target = reinterpret_cast<uint8*>(::google::protobuf::string_as_array(&data));
@@ -535,7 +535,7 @@ TEST(ExtensionSetTest, SerializationToStream) {
   unittest::TestAllExtensions source;
   unittest::TestAllTypes destination;
   TestUtil::SetAllExtensions(&source);
-  int size = source.ByteSize();
+  size_t size = source.ByteSizeLong();
   std::string data;
   data.resize(size);
   {
@@ -558,7 +558,7 @@ TEST(ExtensionSetTest, PackedSerializationToArray) {
   unittest::TestPackedExtensions source;
   unittest::TestPackedTypes destination;
   TestUtil::SetPackedExtensions(&source);
-  int size = source.ByteSize();
+  size_t size = source.ByteSizeLong();
   std::string data;
   data.resize(size);
   uint8* target = reinterpret_cast<uint8*>(::google::protobuf::string_as_array(&data));
@@ -579,7 +579,7 @@ TEST(ExtensionSetTest, PackedSerializationToStream) {
   unittest::TestPackedExtensions source;
   unittest::TestPackedTypes destination;
   TestUtil::SetPackedExtensions(&source);
-  int size = source.ByteSize();
+  size_t size = source.ByteSizeLong();
   std::string data;
   data.resize(size);
   {
@@ -739,12 +739,12 @@ TEST(ExtensionSetTest, SpaceUsedExcludingSelf) {
 #define TEST_SCALAR_EXTENSIONS_SPACE_USED(type, value)                       \
   do {                                                                       \
     unittest::TestAllExtensions message;                                     \
-    const int base_size = message.SpaceUsed();                               \
+    const int base_size = message.SpaceUsedLong();                           \
     message.SetExtension(unittest::optional_##type##_extension, value);      \
     int min_expected_size =                                                  \
         base_size +                                                          \
         sizeof(message.GetExtension(unittest::optional_##type##_extension)); \
-    EXPECT_LE(min_expected_size, message.SpaceUsed());                       \
+    EXPECT_LE(min_expected_size, message.SpaceUsedLong());                   \
   } while (0)
 
   TEST_SCALAR_EXTENSIONS_SPACE_USED(int32, 101);
@@ -763,36 +763,36 @@ TEST(ExtensionSetTest, SpaceUsedExcludingSelf) {
 #undef TEST_SCALAR_EXTENSIONS_SPACE_USED
   {
     unittest::TestAllExtensions message;
-    const int base_size = message.SpaceUsed();
+    const int base_size = message.SpaceUsedLong();
     message.SetExtension(unittest::optional_nested_enum_extension,
                          unittest::TestAllTypes::FOO);
     int min_expected_size =
         base_size +
         sizeof(message.GetExtension(unittest::optional_nested_enum_extension));
-    EXPECT_LE(min_expected_size, message.SpaceUsed());
+    EXPECT_LE(min_expected_size, message.SpaceUsedLong());
   }
   {
     // Strings may cause extra allocations depending on their length; ensure
     // that gets included as well.
     unittest::TestAllExtensions message;
-    const int base_size = message.SpaceUsed();
+    const int base_size = message.SpaceUsedLong();
     const std::string s(
         "this is a fairly large string that will cause some "
         "allocation in order to store it in the extension");
     message.SetExtension(unittest::optional_string_extension, s);
     int min_expected_size = base_size + s.length();
-    EXPECT_LE(min_expected_size, message.SpaceUsed());
+    EXPECT_LE(min_expected_size, message.SpaceUsedLong());
   }
   {
     // Messages also have additional allocation that need to be counted.
     unittest::TestAllExtensions message;
-    const int base_size = message.SpaceUsed();
+    const int base_size = message.SpaceUsedLong();
     unittest::ForeignMessage foreign;
     foreign.set_c(42);
     message.MutableExtension(unittest::optional_foreign_message_extension)
         ->CopyFrom(foreign);
-    int min_expected_size = base_size + foreign.SpaceUsed();
+    int min_expected_size = base_size + foreign.SpaceUsedLong();
-    EXPECT_LE(min_expected_size, message.SpaceUsed());
+    EXPECT_LE(min_expected_size, message.SpaceUsedLong());
   }
 
   // Repeated primitive extensions will increase space used by at least a
@@ -802,23 +802,23 @@ TEST(ExtensionSetTest, SpaceUsedExcludingSelf) {
   //   - Adds a value to the repeated extension, then clears it, establishing
   //     the base size.
   //   - Adds a small number of values, testing that it doesn't increase the
-  //     SpaceUsed()
+  //     SpaceUsedLong()
   //   - Adds a large number of values (requiring allocation in the repeated
-  //     field), and ensures that that allocation is included in SpaceUsed()
+  //     field), and ensures that that allocation is included in SpaceUsedLong()
 #define TEST_REPEATED_EXTENSIONS_SPACE_USED(type, cpptype, value)             \
   do {                                                                        \
     unittest::TestAllExtensions message;                                      \
-    const int base_size = message.SpaceUsed();                                \
+    const size_t base_size = message.SpaceUsedLong();                         \
-    int min_expected_size = sizeof(RepeatedField<cpptype>) + base_size;       \
+    size_t min_expected_size = sizeof(RepeatedField<cpptype>) + base_size;    \
     message.AddExtension(unittest::repeated_##type##_extension, value);       \
     message.ClearExtension(unittest::repeated_##type##_extension);            \
-    const int empty_repeated_field_size = message.SpaceUsed();                \
+    const size_t empty_repeated_field_size = message.SpaceUsedLong();         \
     EXPECT_LE(min_expected_size, empty_repeated_field_size) << #type;         \
     message.AddExtension(unittest::repeated_##type##_extension, value);       \
     message.AddExtension(unittest::repeated_##type##_extension, value);       \
-    EXPECT_EQ(empty_repeated_field_size, message.SpaceUsed()) << #type;       \
+    EXPECT_EQ(empty_repeated_field_size, message.SpaceUsedLong()) << #type;   \
     message.ClearExtension(unittest::repeated_##type##_extension);            \
-    const int old_capacity =                                                  \
+    const size_t old_capacity =                                               \
         message.GetRepeatedExtension(unittest::repeated_##type##_extension)   \
             .Capacity();                                                      \
     EXPECT_GE(old_capacity, kRepeatedFieldLowerClampLimit);                   \
@@ -832,7 +832,7 @@ TEST(ExtensionSetTest, SpaceUsedExcludingSelf) {
                  .Capacity() -                                                \
              old_capacity) +                                                  \
         empty_repeated_field_size;                                            \
-    EXPECT_LE(expected_size, message.SpaceUsed()) << #type;                   \
+    EXPECT_LE(expected_size, message.SpaceUsedLong()) << #type;               \
   } while (0)
 
   TEST_REPEATED_EXTENSIONS_SPACE_USED(int32, int32, 101);
@@ -854,8 +854,9 @@ TEST(ExtensionSetTest, SpaceUsedExcludingSelf) {
   // Repeated strings
   {
     unittest::TestAllExtensions message;
-    const int base_size = message.SpaceUsed();
+    const size_t base_size = message.SpaceUsedLong();
-    int min_expected_size = sizeof(RepeatedPtrField<std::string>) + base_size;
+    size_t min_expected_size =
+        sizeof(RepeatedPtrField<std::string>) + base_size;
     const std::string value(256, 'x');
     // Once items are allocated, they may stick around even when cleared so
     // without the hardcore memory management accessors there isn't a notion of
@@ -865,13 +866,13 @@ TEST(ExtensionSetTest, SpaceUsedExcludingSelf) {
     }
     min_expected_size +=
         (sizeof(value) + value.size()) * (16 - kRepeatedFieldLowerClampLimit);
-    EXPECT_LE(min_expected_size, message.SpaceUsed());
+    EXPECT_LE(min_expected_size, message.SpaceUsedLong());
   }
   // Repeated messages
   {
     unittest::TestAllExtensions message;
-    const int base_size = message.SpaceUsed();
+    const size_t base_size = message.SpaceUsedLong();
-    int min_expected_size =
+    size_t min_expected_size =
         sizeof(RepeatedPtrField<unittest::ForeignMessage>) + base_size;
     unittest::ForeignMessage prototype;
     prototype.set_c(2);
@@ -880,8 +881,8 @@ TEST(ExtensionSetTest, SpaceUsedExcludingSelf) {
           ->CopyFrom(prototype);
     }
     min_expected_size +=
-        (16 - kRepeatedFieldLowerClampLimit) * prototype.SpaceUsed();
+        (16 - kRepeatedFieldLowerClampLimit) * prototype.SpaceUsedLong();
-    EXPECT_LE(min_expected_size, message.SpaceUsed());
+    EXPECT_LE(min_expected_size, message.SpaceUsedLong());
   }
 }
 

src/google/protobuf/generated_enum_reflection.h

@@ -43,6 +43,7 @@
 
 #include <google/protobuf/generated_enum_util.h>
 #include <google/protobuf/port.h>
+#include <google/protobuf/stubs/strutil.h>
 
 #ifdef SWIG
 #error "You cannot SWIG proto headers"
@@ -71,10 +72,10 @@ namespace internal {
 // an enum name of the given type, returning true and filling in value on
 // success, or returning false and leaving value unchanged on failure.
 PROTOBUF_EXPORT bool ParseNamedEnum(const EnumDescriptor* descriptor,
-                                    const std::string& name, int* value);
+                                    StringPiece name, int* value);
 
 template <typename EnumType>
-bool ParseNamedEnum(const EnumDescriptor* descriptor, const std::string& name,
+bool ParseNamedEnum(const EnumDescriptor* descriptor, StringPiece name,
                     EnumType* value) {
   int tmp;
   if (!ParseNamedEnum(descriptor, name, &tmp)) return false;

src/google/protobuf/generated_message_reflection.cc

@@ -50,6 +50,7 @@
 #include <google/protobuf/repeated_field.h>
 #include <google/protobuf/unknown_field_set.h>
 #include <google/protobuf/wire_format.h>
+#include <google/protobuf/stubs/strutil.h>
 
 
 #include <google/protobuf/port_def.inc>
@@ -81,7 +82,7 @@ bool IsMapFieldInApi(const FieldDescriptor* field) { return field->is_map(); }
 
 namespace internal {
 
-bool ParseNamedEnum(const EnumDescriptor* descriptor, const std::string& name,
+bool ParseNamedEnum(const EnumDescriptor* descriptor, StringPiece name,
                     int* value) {
   const EnumValueDescriptor* d = descriptor->FindValueByName(name);
   if (d == nullptr) return false;

src/google/protobuf/lite_unittest.cc

@@ -613,7 +613,7 @@ TEST(Lite, AllLite28) {
     protobuf_unittest::TestMapLite message1, message2;
     std::string data;
     MapLiteTestUtil::SetMapFields(&message1);
-    int size = message1.ByteSize();
+    size_t size = message1.ByteSizeLong();
     data.resize(size);
     ::google::protobuf::uint8* start = reinterpret_cast<::google::protobuf::uint8*>(::google::protobuf::string_as_array(&data));
     ::google::protobuf::uint8* end = message1.SerializeWithCachedSizesToArray(start);
@@ -630,7 +630,7 @@ TEST(Lite, AllLite29) {
     // Test the generated SerializeWithCachedSizes()
     protobuf_unittest::TestMapLite message1, message2;
     MapLiteTestUtil::SetMapFields(&message1);
-    int size = message1.ByteSize();
+    size_t size = message1.ByteSizeLong();
     std::string data;
     data.resize(size);
     {

src/google/protobuf/map.h

@@ -42,9 +42,14 @@
 #include <iterator>
 #include <limits>  // To support Visual Studio 2008
 #include <map>
+#include <string>
 #include <type_traits>
 #include <utility>
 
+#if defined(__cpp_lib_string_view)
+#include <string_view>
+#endif  // defined(__cpp_lib_string_view)
+
 #include <google/protobuf/stubs/common.h>
 #include <google/protobuf/arena.h>
 #include <google/protobuf/generated_enum_util.h>
@@ -186,6 +191,67 @@ using KeyForTree =
     typename std::conditional<std::is_scalar<T>::value, T,
                               std::reference_wrapper<const T>>::type;
 
+// Default case: Not transparent.
+// We use std::hash<key_type>/std::less<key_type> and all the lookup functions
+// only accept `key_type`.
+template <typename key_type>
+struct TransparentSupport {
+  using hash = std::hash<key_type>;
+  using less = std::less<key_type>;
+
+  static bool Equals(const key_type& a, const key_type& b) { return a == b; }
+
+  template <typename K>
+  using key_arg = key_type;
+};
+
+#if defined(__cpp_lib_string_view)
+// If std::string_view is available, we add transparent support for std::string
+// keys. We use std::hash<std::string_view> as it supports the input types we
+// care about. The lookup functions accept arbitrary `K`. This will include any
+// key type that is convertible to std::string_view.
+template <>
+struct TransparentSupport<std::string> {
+  static std::string_view ImplicitConvert(std::string_view str) { return str; }
+  // If the element is not convertible to std::string_view, try to convert to
+  // std::string first.
+  // The template makes this overload lose resolution when both have the same
+  // rank otherwise.
+  template <typename = void>
+  static std::string_view ImplicitConvert(const std::string& str) {
+    return str;
+  }
+
+  struct hash : private std::hash<std::string_view> {
+    using is_transparent = void;
+
+    template <typename T>
+    size_t operator()(const T& str) const {
+      return base()(ImplicitConvert(str));
+    }
+
+   private:
+    const std::hash<std::string_view>& base() const { return *this; }
+  };
+  struct less {
+    using is_transparent = void;
+
+    template <typename T, typename U>
+    bool operator()(const T& t, const U& u) const {
+      return ImplicitConvert(t) < ImplicitConvert(u);
+    }
+  };
+
+  template <typename T, typename U>
+  static bool Equals(const T& t, const U& u) {
+    return ImplicitConvert(t) == ImplicitConvert(u);
+  }
+
+  template <typename K>
+  using key_arg = K;
+};
+#endif  // defined(__cpp_lib_string_view)
+
 }  // namespace internal
 
 // This is the class for Map's internal value_type. Instead of using
@@ -240,7 +306,7 @@ class Map {
   using const_reference = const value_type&;
 
   using size_type = size_t;
-  using hasher = std::hash<Key>;
+  using hasher = typename internal::TransparentSupport<Key>::hash;
 
   Map() : arena_(nullptr), default_enum_value_(0) { Init(); }
   explicit Map(Arena* arena) : arena_(arena), default_enum_value_(0) { Init(); }
@@ -357,7 +423,8 @@ class Map {
     // class per key type.
     using TreeAllocator = typename Allocator::template rebind<
         std::pair<const internal::KeyForTree<Key>, void*>>::other;
-    using Tree = std::map<internal::KeyForTree<Key>, void*, std::less<Key>,
+    using Tree = std::map<internal::KeyForTree<Key>, void*,
+                          typename internal::TransparentSupport<Key>::less,
                           TreeAllocator>;
     using TreeIterator = typename Tree::iterator;
 
@@ -541,9 +608,10 @@ class Map {
     size_type size() const { return num_elements_; }
     bool empty() const { return size() == 0; }
 
-    iterator find(const Key& k) { return iterator(FindHelper(k).first); }
+    template <typename K>
-    const_iterator find(const Key& k) const { return find(k, nullptr); }
+    iterator find(const K& k) {
-    bool contains(const Key& k) const { return find(k) != end(); }
+      return iterator(FindHelper(k).first);
+    }
 
     // Insert the key into the map, if not present. In that case, the value will
     // be value initialized.
@@ -611,16 +679,18 @@ class Map {
     const_iterator find(const Key& k, TreeIterator* it) const {
       return FindHelper(k, it).first;
     }
-    std::pair<const_iterator, size_type> FindHelper(const Key& k) const {
+    template <typename K>
+    std::pair<const_iterator, size_type> FindHelper(const K& k) const {
       return FindHelper(k, nullptr);
     }
-    std::pair<const_iterator, size_type> FindHelper(const Key& k,
+    template <typename K>
+    std::pair<const_iterator, size_type> FindHelper(const K& k,
                                                     TreeIterator* it) const {
       size_type b = BucketNumber(k);
       if (TableEntryIsNonEmptyList(b)) {
         Node* node = static_cast<Node*>(table_[b]);
         do {
-          if (IsMatch(node->kv.first, k)) {
+          if (internal::TransparentSupport<Key>::Equals(node->kv.first, k)) {
             return std::make_pair(const_iterator(node, this, b), b);
           } else {
             node = node->next;
@@ -675,9 +745,29 @@ class Map {
       return result;
     }
 
+    // Returns whether we should insert after the head of the list. For
+    // non-optimized builds, we randomly decide whether to insert right at the
+    // head of the list or just after the head. This helps add a little bit of
+    // non-determinism to the map ordering.
+    bool ShouldInsertAfterHead(void* node) {
+#ifdef NDEBUG
+      return false;
+#else
+      // Doing modulo with a prime mixes the bits more.
+      return (reinterpret_cast<uintptr_t>(node) ^ seed_) % 13 > 6;
+#endif
+    }
+
     // Helper for InsertUnique.  Handles the case where bucket b is a
     // not-too-long linked list.
     iterator InsertUniqueInList(size_type b, Node* node) {
+      if (table_[b] != nullptr && ShouldInsertAfterHead(node)) {
+        Node* first = static_cast<Node*>(table_[b]);
+        node->next = first->next;
+        first->next = node;
+        return iterator(node, this, b);
+      }
+
       node->next = static_cast<Node*>(table_[b]);
       table_[b] = static_cast<void*>(node);
       return iterator(node, this, b);
@@ -767,7 +857,7 @@ class Map {
       Tree* tree = static_cast<Tree*>(table[index]);
       typename Tree::iterator tree_it = tree->begin();
       do {
-        InsertUnique(BucketNumber(tree_it->first),
+        InsertUnique(BucketNumber(std::cref(tree_it->first).get()),
                      NodeFromTreeIterator(tree_it));
       } while (++tree_it != tree->end());
       DestroyTree(tree);
@@ -848,12 +938,18 @@ class Map {
       return count >= kMaxLength;
     }
 
-    size_type BucketNumber(const Key& k) const {
+    template <typename K>
-      size_type h = hash_function()(k);
+    size_type BucketNumber(const K& k) const {
-      return (h + seed_) & (num_buckets_ - 1);
+      // We xor the hash value against the random seed so that we effectively
-    }
+      // have a random hash function.
+      uint64 h = hash_function()(k) ^ seed_;
 
-    bool IsMatch(const Key& k0, const Key& k1) const { return k0 == k1; }
+      // We use the multiplication method to determine the bucket number from
+      // the hash value. The constant kPhi (suggested by Knuth) is roughly
+      // (sqrt(5) - 1) / 2 * 2^64.
+      constexpr uint64 kPhi = uint64{0x9e3779b97f4a7c15};
+      return ((kPhi * h) >> 32) & (num_buckets_ - 1);
+    }
 
     // Return a power of two no less than max(kMinTableSize, n).
     // Assumes either n < kMinTableSize or n is a power of two.
@@ -899,7 +995,10 @@ class Map {
 
     // Return a randomish value.
     size_type Seed() const {
-      size_type s = static_cast<size_type>(reinterpret_cast<uintptr_t>(this));
+      // We get a little bit of randomness from the address of the map. The
+      // lower bits are not very random, due to alignment, so we discard them
+      // and shift the higher bits into their place.
+      size_type s = reinterpret_cast<uintptr_t>(this) >> 12;
 #if defined(__x86_64__) && defined(__GNUC__) && \
     !defined(GOOGLE_PROTOBUF_NO_RDTSC)
       uint32 hi, lo;
@@ -922,6 +1021,10 @@ class Map {
     GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(InnerMap);
   };  // end of class InnerMap
 
+  template <typename LookupKey>
+  using key_arg = typename internal::TransparentSupport<
+      key_type>::template key_arg<LookupKey>;
+
  public:
   // Iterators
   class const_iterator {
@@ -1014,30 +1117,44 @@ class Map {
 
   // Element access
   T& operator[](const key_type& key) { return (*elements_)[key].second; }
-  const T& at(const key_type& key) const {
+
+  template <typename K = key_type>
+  const T& at(const key_arg<K>& key) const {
     const_iterator it = find(key);
-    GOOGLE_CHECK(it != end()) << "key not found: " << key;
+    GOOGLE_CHECK(it != end()) << "key not found: " << static_cast<Key>(key);
     return it->second;
   }
-  T& at(const key_type& key) {
+
+  template <typename K = key_type>
+  T& at(const key_arg<K>& key) {
     iterator it = find(key);
-    GOOGLE_CHECK(it != end()) << "key not found: " << key;
+    GOOGLE_CHECK(it != end()) << "key not found: " << static_cast<Key>(key);
     return it->second;
   }
 
   // Lookup
-  size_type count(const key_type& key) const {
+  template <typename K = key_type>
-    const_iterator it = find(key);
+  size_type count(const key_arg<K>& key) const {
-    GOOGLE_DCHECK(it == end() || key == it->first);
+    return find(key) == end() ? 0 : 1;
-    return it == end() ? 0 : 1;
   }
-  const_iterator find(const key_type& key) const {
+
+  template <typename K = key_type>
+  const_iterator find(const key_arg<K>& key) const {
     return const_iterator(iterator(elements_->find(key)));
   }
-  iterator find(const key_type& key) { return iterator(elements_->find(key)); }
+  template <typename K = key_type>
-  bool contains(const Key& key) const { return elements_->contains(key); }
+  iterator find(const key_arg<K>& key) {
+    return iterator(elements_->find(key));
+  }
+
+  template <typename K = key_type>
+  bool contains(const key_arg<K>& key) const {
+    return find(key) != end();
+  }
+
+  template <typename K = key_type>
   std::pair<const_iterator, const_iterator> equal_range(
-      const key_type& key) const {
+      const key_arg<K>& key) const {
     const_iterator it = find(key);
     if (it == end()) {
       return std::pair<const_iterator, const_iterator>(it, it);
@@ -1046,7 +1163,9 @@ class Map {
       return std::pair<const_iterator, const_iterator>(begin, it);
     }
   }
-  std::pair<iterator, iterator> equal_range(const key_type& key) {
+
+  template <typename K = key_type>
+  std::pair<iterator, iterator> equal_range(const key_arg<K>& key) {
     iterator it = find(key);
     if (it == end()) {
       return std::pair<iterator, iterator>(it, it);
@@ -1079,7 +1198,8 @@ class Map {
   }
 
   // Erase and clear
-  size_type erase(const key_type& key) {
+  template <typename K = key_type>
+  size_type erase(const key_arg<K>& key) {
     iterator it = find(key);
     if (it == end()) {
       return 0;

src/google/protobuf/map_test.cc

@@ -980,6 +980,107 @@ TEST_F(MapImplTest, CopyAssignMapIterator) {
   EXPECT_EQ(it1.GetKey().GetInt32Value(), it2.GetKey().GetInt32Value());
 }
 
+// Attempts to verify that a map with keys a and b has a random ordering. This
+// function returns true if it succeeds in observing both possible orderings.
+bool MapOrderingIsRandom(int a, int b) {
+  bool saw_a_first = false;
+  bool saw_b_first = false;
+
+  for (int i = 0; i < 50; ++i) {
+    Map<int32, int32> m;
+    m[a] = 0;
+    m[b] = 0;
+    int32 first_element = m.begin()->first;
+    if (first_element == a) saw_a_first = true;
+    if (first_element == b) saw_b_first = true;
+    if (saw_a_first && saw_b_first) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+// This test verifies that the iteration order is reasonably random even for
+// small maps. Currently we only have sufficient randomness for debug builds and
+// builds where we can use the RDTSC instruction, so we only test for those
+// builds.
+#if defined(__x86_64__) && defined(__GNUC__) && \
+    !defined(GOOGLE_PROTOBUF_NO_RDTSC)
+TEST_F(MapImplTest, RandomOrdering) {
+  for (int i = 0; i < 10; ++i) {
+    for (int j = i + 1; j < 10; ++j) {
+      EXPECT_TRUE(MapOrderingIsRandom(i, j))
+          << "Map with keys " << i << " and " << j
+          << " has deterministic ordering";
+    }
+  }
+}
+#endif
+
+template <typename Key>
+void TestTransparent(const Key& key, const Key& miss_key) {
+  Map<std::string, int> m;
+  const auto& cm = m;
+
+  m.insert({"ABC", 1});
+
+  const auto abc_it = m.begin();
+
+  m.insert({"DEF", 2});
+
+  using testing::Pair;
+  using testing::UnorderedElementsAre;
+
+  EXPECT_EQ(m.at(key), 1);
+  EXPECT_EQ(cm.at(key), 1);
+
+#ifdef PROTOBUF_HAS_DEATH_TEST
+  EXPECT_DEATH(m.at(miss_key), "");
+  EXPECT_DEATH(cm.at(miss_key), "");
+#endif  // PROTOBUF_HAS_DEATH_TEST
+
+  EXPECT_EQ(m.count(key), 1);
+  EXPECT_EQ(cm.count(key), 1);
+  EXPECT_EQ(m.count(miss_key), 0);
+  EXPECT_EQ(cm.count(miss_key), 0);
+
+  EXPECT_EQ(m.find(key), abc_it);
+  EXPECT_EQ(cm.find(key), abc_it);
+  EXPECT_EQ(m.find(miss_key), m.end());
+  EXPECT_EQ(cm.find(miss_key), cm.end());
+
+  EXPECT_TRUE(m.contains(key));
+  EXPECT_TRUE(cm.contains(key));
+  EXPECT_FALSE(m.contains(miss_key));
+  EXPECT_FALSE(cm.contains(miss_key));
+
+  EXPECT_THAT(m.equal_range(key), Pair(abc_it, std::next(abc_it)));
+  EXPECT_THAT(cm.equal_range(key), Pair(abc_it, std::next(abc_it)));
+  EXPECT_THAT(m.equal_range(miss_key), Pair(m.end(), m.end()));
+  EXPECT_THAT(cm.equal_range(miss_key), Pair(m.end(), m.end()));
+
+  EXPECT_THAT(m, UnorderedElementsAre(Pair("ABC", 1), Pair("DEF", 2)));
+  EXPECT_EQ(m.erase(key), 1);
+  EXPECT_THAT(m, UnorderedElementsAre(Pair("DEF", 2)));
+  EXPECT_EQ(m.erase(key), 0);
+  EXPECT_EQ(m.erase(miss_key), 0);
+  EXPECT_THAT(m, UnorderedElementsAre(Pair("DEF", 2)));
+}
+
+TEST_F(MapImplTest, TransparentLookupForString) {
+  TestTransparent("ABC", "LKJ");
+  TestTransparent(std::string("ABC"), std::string("LKJ"));
+#if defined(__cpp_lib_string_view)
+  TestTransparent(std::string_view("ABC"), std::string_view("LKJ"));
+#endif  // defined(__cpp_lib_string_view)
+
+  // std::reference_wrapper
+  std::string abc = "ABC", lkj = "LKJ";
+  TestTransparent(std::ref(abc), std::ref(lkj));
+  TestTransparent(std::cref(abc), std::cref(lkj));
+}
+
 // Map Field Reflection Test ========================================
 
 static int Func(int i, int j) { return i * j; }
@@ -2408,45 +2509,45 @@ TEST(GeneratedMapFieldTest, IsInitialized) {
 
 TEST(GeneratedMapFieldTest, MessagesMustMerge) {
   unittest::TestRequiredMessageMap map_message;
+
   unittest::TestRequired with_dummy4;
   with_dummy4.set_a(97);
-  with_dummy4.set_b(0);
+  with_dummy4.set_b(91);
-  with_dummy4.set_c(0);
   with_dummy4.set_dummy4(98);
-
+  EXPECT_FALSE(with_dummy4.IsInitialized());
-  EXPECT_TRUE(with_dummy4.IsInitialized());
   (*map_message.mutable_map_field())[0] = with_dummy4;
-  EXPECT_TRUE(map_message.IsInitialized());
+  EXPECT_FALSE(map_message.IsInitialized());
-  std::string s = map_message.SerializeAsString();
 
-  // Modify s so that there are two values in the entry for key 0.
+  unittest::TestRequired with_dummy5;
-  // The first will have no value for c.  The second will have no value for a.
+  with_dummy5.set_b(0);
-  // Those are required fields.  Also, make some other little changes, to
+  with_dummy5.set_c(33);
-  // ensure we are merging the two values (because they're messages).
+  with_dummy5.set_dummy5(99);
-  ASSERT_EQ(s.size() - 2, s[1]);  // encoding of the length of what follows
+  EXPECT_FALSE(with_dummy5.IsInitialized());
-  std::string encoded_val(s.data() + 4, s.data() + s.size());
+  (*map_message.mutable_map_field())[0] = with_dummy5;
-  // In s, change the encoding of c to an encoding of dummy32.
+  EXPECT_FALSE(map_message.IsInitialized());
-  s[s.size() - 3] -= 8;
-  // Make encoded_val slightly different from what's in s.
-  encoded_val[encoded_val.size() - 1] += 33;  // Encode c = 33.
-  for (int i = 0; i < encoded_val.size(); i++) {
-    if (encoded_val[i] == 97) {
-      // Encode b = 91 instead of a = 97.  But this won't matter, because
-      // we also encode b = 0 right after this.  The point is to leave out
-      // a required field, and make sure the parser doesn't complain, because
-      // every required field is set after the merge of the two values.
-      encoded_val[i - 1] += 16;
-      encoded_val[i] = 91;
-    } else if (encoded_val[i] == 98) {
-      // Encode dummy5 = 99 instead of dummy4 = 98.
-      encoded_val[i - 1] += 8;  // The tag for dummy5 is 8 more.
-      encoded_val[i]++;
-      break;
-    }
-  }
 
-  s += encoded_val;            // Add the second message.
+  // The wire format of MapEntry is straightforward (*) and can be manually
-  s[1] += encoded_val.size();  // Adjust encoded size.
+  // constructed to force merging of two uninitialized messages that would
+  // result in an initialized message.
+  //
+  // (*) http://google3/net/proto2/internal/map_test.cc?l=2433&rcl=310012028
+  std::string dummy4_s = with_dummy4.SerializePartialAsString();
+  std::string dummy5_s = with_dummy5.SerializePartialAsString();
+  int payload_size = dummy4_s.size() + dummy5_s.size();
+  // Makes sure the payload size fits into one byte.
+  ASSERT_LT(payload_size, 128);
+
+  std::string s(6, 0);
+  char* p = &s[0];
+  *p++ = WireFormatLite::MakeTag(1, WireFormatLite::WIRETYPE_LENGTH_DELIMITED);
+  // Length: 2B for key tag & val and 2B for val tag and length of the following
+  // payload.
+  *p++ = 4 + payload_size;
+  *p++ = WireFormatLite::MakeTag(1, WireFormatLite::WIRETYPE_VARINT);
+  *p++ = 0;
+  *p++ = WireFormatLite::MakeTag(2, WireFormatLite::WIRETYPE_LENGTH_DELIMITED);
+  *p++ = payload_size;
+  StrAppend(&s, dummy4_s, dummy5_s);
 
   // Test key then value then value.
   int key = 0;
@@ -2983,10 +3084,9 @@ TEST(WireFormatForMapFieldTest, SerializeMap) {
     ASSERT_FALSE(output.HadError());
   }
 
-  // Should be the same.
+  // Should parse to the same message.
-  // Don't use EXPECT_EQ here because we're comparing raw binary data and
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, generated_data));
-  // we really don't want it dumped to stdout on failure.
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, dynamic_data));
-  EXPECT_TRUE(dynamic_data == generated_data);
 }
 
 TEST(WireFormatForMapFieldTest, SerializeMapDynamicMessage) {
@@ -3161,20 +3261,6 @@ static std::string DeterministicSerialization(const T& t) {
   return result;
 }
 
-// Helper to test the serialization of the first arg against a golden file.
-static void TestDeterministicSerialization(const protobuf_unittest::TestMaps& t,
-                                           const std::string& filename) {
-  std::string expected;
-  GOOGLE_CHECK_OK(File::GetContents(
-      TestUtil::GetTestDataPath("net/proto2/internal/testdata/" + filename),
-      &expected, true));
-  const std::string actual = DeterministicSerialization(t);
-  EXPECT_EQ(expected, actual);
-  protobuf_unittest::TestMaps u;
-  EXPECT_TRUE(u.ParseFromString(actual));
-  EXPECT_TRUE(util::MessageDifferencer::Equals(u, t));
-}
-
 // Helper for MapSerializationTest.  Return a 7-bit ASCII string.
 static std::string ConstructKey(uint64 n) {
   std::string s(n % static_cast<uint64>(9), '\0');
@@ -3219,7 +3305,17 @@ TEST(MapSerializationTest, Deterministic) {
     frog = frog * multiplier + i;
     frog ^= (frog >> 41);
   }
-  TestDeterministicSerialization(t, "golden_message_maps");
+
+  // Verifies if two consecutive calls to deterministic serialization produce
+  // the same bytes. Deterministic serialization means the same serialization
+  // bytes in the same binary.
+  const std::string s1 = DeterministicSerialization(t);
+  const std::string s2 = DeterministicSerialization(t);
+  EXPECT_EQ(s1, s2);
+
+  protobuf_unittest::TestMaps u;
+  EXPECT_TRUE(u.ParseFromString(s1));
+  EXPECT_TRUE(util::MessageDifferencer::Equals(u, t));
 }
 
 TEST(MapSerializationTest, DeterministicSubmessage) {

src/google/protobuf/map_test_util_impl.h

@@ -405,7 +405,7 @@ void MapTestUtilImpl::ExpectMapFieldsSetInitialized(const MapMessage& message) {
   EXPECT_EQ("", message.map_string_string().at("0"));
   EXPECT_EQ("", message.map_int32_bytes().at(0));
   EXPECT_EQ(enum_value, message.map_int32_enum().at(0));
-  EXPECT_EQ(0, message.map_int32_foreign_message().at(0).ByteSize());
+  EXPECT_EQ(0, message.map_int32_foreign_message().at(0).ByteSizeLong());
 }
 
 template <typename EnumType, EnumType enum_value0, EnumType enum_value1,

src/google/protobuf/no_field_presence_test.cc

@@ -567,7 +567,7 @@ TEST(NoFieldPresenceTest, OneofPresence) {
   message.Clear();
   message.set_oneof_string("test");
   message.clear_oneof_string();
-  EXPECT_EQ(0, message.ByteSize());
+  EXPECT_EQ(0, message.ByteSizeLong());
 }
 
 }  // namespace

src/google/protobuf/port_def.inc

@@ -662,3 +662,13 @@ PROTOBUF_EXPORT_TEMPLATE_TEST(DEFAULT, __declspec(dllimport));
 #else
 #define PROTOBUF_THREAD_LOCAL __thread
 #endif
+
+// For enabling message owned arena, one major blocker is semantic change from
+// moving to copying when there is ownership transfer (e.g., move ctor, swap,
+// set allocated, release). This change not only causes performance regression
+// but also breaks users code (e.g., dangling reference). For top-level
+// messages, since it owns the arena, we can mitigate the issue by transferring
+// ownership of arena. However, we cannot do that for nested messages. In order
+// to tell how many usages of nested messages affected by message owned arena,
+// we need to simulate the arena ownership.
+#define PROTOBUF_MESSAGE_OWNED_ARENA_EXPERIMENT

src/google/protobuf/port_undef.inc

@@ -84,6 +84,7 @@
 #undef PROTOBUF_EXPORT_TEMPLATE_STYLE_MATCH_DECLSPEC_dllimport
 #undef PROTOBUF_FINAL
 #undef PROTOBUF_THREAD_LOCAL
+#undef PROTOBUF_MESSAGE_OWNED_ARENA_EXPERIMENT
 
 // Restore macro that may have been #undef'd in port_def.inc.
 #ifdef _MSC_VER

src/google/protobuf/preserve_unknown_enum_test.cc

@@ -137,7 +137,7 @@ TEST(PreserveUnknownEnumTest, Proto2HidesUnknownValues) {
   // The intermediate message has everything in its "unknown fields".
   proto2_preserve_unknown_enum_unittest::MyMessage message2 = message;
   message2.DiscardUnknownFields();
-  EXPECT_EQ(0, message2.ByteSize());
+  EXPECT_EQ(0, message2.ByteSizeLong());
 
   // But when we pass it to the correct structure, all values are there.
   serialized.clear();
@@ -165,7 +165,7 @@ TEST(PreserveUnknownEnumTest, DynamicProto2HidesUnknownValues) {
   proto2_preserve_unknown_enum_unittest::MyMessage message2;
   message2.CopyFrom(*message);
   message2.DiscardUnknownFields();
-  EXPECT_EQ(0, message2.ByteSize());
+  EXPECT_EQ(0, message2.ByteSizeLong());
 
   // But when we pass it to the correct structure, all values are there.
   serialized.clear();

src/google/protobuf/proto3_arena_unittest.cc

@@ -138,7 +138,7 @@ TEST(Proto3ArenaTest, UnknownFields) {
   // We can modify this UnknownFieldSet.
   unknown_fields->AddVarint(1, 2);
   // And the unknown fields should be changed.
-  ASSERT_NE(original.ByteSize(), arena_message->ByteSize());
+  ASSERT_NE(original.ByteSizeLong(), arena_message->ByteSizeLong());
   ASSERT_FALSE(
       arena_message->GetReflection()->GetUnknownFields(*arena_message).empty());
 }
@@ -203,7 +203,7 @@ TEST(Proto3OptionalTest, OptionalFields) {
   msg.set_optional_int32(0);
   EXPECT_TRUE(msg.has_optional_int32());
 
-  string serialized;
+  std::string serialized;
   msg.SerializeToString(&serialized);
   EXPECT_GT(serialized.size(), 0);
 
@@ -236,7 +236,7 @@ TEST(Proto3OptionalTest, OptionalField) {
   msg.set_optional_int32(0);
   EXPECT_TRUE(msg.has_optional_int32());
 
-  string serialized;
+  std::string serialized;
   msg.SerializeToString(&serialized);
   EXPECT_GT(serialized.size(), 0);
 

src/google/protobuf/struct.pb.h

@@ -100,7 +100,7 @@ inline const std::string& NullValue_Name(T enum_t_value) {
     NullValue_descriptor(), enum_t_value);
 }
 inline bool NullValue_Parse(
-    const std::string& name, NullValue* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, NullValue* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<NullValue>(
     NullValue_descriptor(), name, value);
 }

src/google/protobuf/stubs/port.h

@@ -117,6 +117,8 @@
 namespace google {
 namespace protobuf {
 
+using ConstStringParam = const std::string &;
+
 typedef unsigned int uint;
 
 typedef int8_t int8;

src/google/protobuf/test_util_lite.cc

@@ -1351,7 +1351,7 @@ void TestUtilLite::ExpectExtensionsClear(
   std::string serialized;
   ASSERT_TRUE(message.SerializeToString(&serialized));
   EXPECT_EQ("", serialized);
-  EXPECT_EQ(0, message.ByteSize());
+  EXPECT_EQ(0, message.ByteSizeLong());
 
   // has_blah() should initially be false for all optional fields.
   EXPECT_FALSE(message.HasExtension(unittest::optional_int32_extension_lite));

src/google/protobuf/text_format_unittest.cc

@@ -55,6 +55,7 @@
 #include <google/protobuf/io/tokenizer.h>
 #include <google/protobuf/io/zero_copy_stream_impl.h>
 #include <google/protobuf/stubs/strutil.h>
+#include <gmock/gmock.h>
 #include <google/protobuf/testing/googletest.h>
 #include <gtest/gtest.h>
 #include <google/protobuf/stubs/substitute.h>
@@ -346,14 +347,13 @@ TEST_F(TextFormatTest, PrintUnknownMessage) {
   UnknownFieldSet unknown_fields;
   EXPECT_TRUE(unknown_fields.ParseFromString(data));
   EXPECT_TRUE(TextFormat::PrintUnknownFieldsToString(unknown_fields, &text));
-  EXPECT_EQ(
+  // Field 44 and 48 can be printed in any order.
-      "44: \"abc\"\n"
+  EXPECT_THAT(text, testing::HasSubstr("44: \"abc\"\n"
                                        "44: \"def\"\n"
-      "44: \"\"\n"
+                                       "44: \"\"\n"));
-      "48 {\n"
+  EXPECT_THAT(text, testing::HasSubstr("48 {\n"
                                        "  1: 123\n"
-      "}\n",
+                                       "}\n"));
-      text);
 }
 
 TEST_F(TextFormatTest, PrintDeeplyNestedUnknownMessage) {

src/google/protobuf/type.pb.h

@@ -121,7 +121,7 @@ inline const std::string& Field_Kind_Name(T enum_t_value) {
     Field_Kind_descriptor(), enum_t_value);
 }
 inline bool Field_Kind_Parse(
-    const std::string& name, Field_Kind* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, Field_Kind* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<Field_Kind>(
     Field_Kind_descriptor(), name, value);
 }
@@ -148,7 +148,7 @@ inline const std::string& Field_Cardinality_Name(T enum_t_value) {
     Field_Cardinality_descriptor(), enum_t_value);
 }
 inline bool Field_Cardinality_Parse(
-    const std::string& name, Field_Cardinality* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, Field_Cardinality* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<Field_Cardinality>(
     Field_Cardinality_descriptor(), name, value);
 }
@@ -173,7 +173,7 @@ inline const std::string& Syntax_Name(T enum_t_value) {
     Syntax_descriptor(), enum_t_value);
 }
 inline bool Syntax_Parse(
-    const std::string& name, Syntax* value) {
+    ::PROTOBUF_NAMESPACE_ID::ConstStringParam name, Syntax* value) {
   return ::PROTOBUF_NAMESPACE_ID::internal::ParseNamedEnum<Syntax>(
     Syntax_descriptor(), name, value);
 }
@@ -598,7 +598,7 @@ class PROTOBUF_EXPORT Field PROTOBUF_FINAL :
       "Incorrect type passed to function Kind_Name.");
     return Field_Kind_Name(enum_t_value);
   }
-  static inline bool Kind_Parse(const std::string& name,
+  static inline bool Kind_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       Kind* value) {
     return Field_Kind_Parse(name, value);
   }
@@ -632,7 +632,7 @@ class PROTOBUF_EXPORT Field PROTOBUF_FINAL :
       "Incorrect type passed to function Cardinality_Name.");
     return Field_Cardinality_Name(enum_t_value);
   }
-  static inline bool Cardinality_Parse(const std::string& name,
+  static inline bool Cardinality_Parse(::PROTOBUF_NAMESPACE_ID::ConstStringParam name,
       Cardinality* value) {
     return Field_Cardinality_Parse(name, value);
   }

src/google/protobuf/unknown_field_set_unittest.cc

@@ -37,6 +37,8 @@
 
 #include <google/protobuf/unknown_field_set.h>
 
+#include <unordered_set>
+
 #include <google/protobuf/stubs/callback.h>
 #include <google/protobuf/stubs/common.h>
 #include <google/protobuf/stubs/logging.h>
@@ -113,30 +115,32 @@ class UnknownFieldSetTest : public testing::Test {
 namespace {
 
 TEST_F(UnknownFieldSetTest, AllFieldsPresent) {
-  // All fields of TestAllTypes should be present, in numeric order (because
+  // Verifies the following:
-  // that's the order we parsed them in).  Fields that are not valid field
+  // --all unknown tags belong to TestAllTypes.
-  // numbers of TestAllTypes should NOT be present.
+  // --all fields in TestAllTypes is present in UnknownFieldSet except unset
+  //   oneof fields.
+  //
+  // Should handle repeated fields that may appear multiple times in
+  // UnknownFieldSet.
 
-  int pos = 0;
+  int non_oneof_count = 0;
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    if (!descriptor_->field(i)->containing_oneof()) {
+      non_oneof_count++;
+    }
+  }
 
-  for (int i = 0; i < 1000; i++) {
+  std::unordered_set<uint32> unknown_tags;
-    const FieldDescriptor* field = descriptor_->FindFieldByNumber(i);
+  for (int i = 0; i < unknown_fields_->field_count(); i++) {
-    if (field != NULL) {
+    unknown_tags.insert(unknown_fields_->field(i).number());
-      ASSERT_LT(pos, unknown_fields_->field_count());
-      // Do not check oneof field if it is not set.
-      if (field->containing_oneof() == NULL) {
-        EXPECT_EQ(i, unknown_fields_->field(pos++).number());
-      } else if (i == unknown_fields_->field(pos).number()) {
-        pos++;
   }
-      if (field->is_repeated()) {
+
-        // Should have a second instance.
+  for (uint32 t : unknown_tags) {
-        ASSERT_LT(pos, unknown_fields_->field_count());
+    EXPECT_NE(descriptor_->FindFieldByNumber(t), nullptr);
-        EXPECT_EQ(i, unknown_fields_->field(pos++).number());
   }
-    }
+
-  }
+  EXPECT_EQ(non_oneof_count + descriptor_->oneof_decl_count(),
-  EXPECT_EQ(unknown_fields_->field_count(), pos);
+            unknown_tags.size());
 }
 
 TEST_F(UnknownFieldSetTest, Varint) {
@@ -246,7 +250,7 @@ TEST_F(UnknownFieldSetTest, SerializeViaReflection) {
   {
     io::StringOutputStream raw_output(&data);
     io::CodedOutputStream output(&raw_output);
-    int size = WireFormat::ByteSize(empty_message_);
+    size_t size = WireFormat::ByteSize(empty_message_);
     WireFormat::SerializeWithCachedSizes(empty_message_, size, &output);
     ASSERT_FALSE(output.HadError());
   }
@@ -536,29 +540,29 @@ TEST_F(UnknownFieldSetTest, SpaceUsed) {
 
   // Make sure an unknown field set has zero space used until a field is
   // actually added.
-  int base_size = empty_message.SpaceUsed();
+  size_t base_size = empty_message.SpaceUsedLong();
   UnknownFieldSet* unknown_fields = empty_message.mutable_unknown_fields();
-  EXPECT_EQ(base_size, empty_message.SpaceUsed());
+  EXPECT_EQ(base_size, empty_message.SpaceUsedLong());
 
-  // Make sure each thing we add to the set increases the SpaceUsed().
+  // Make sure each thing we add to the set increases the SpaceUsedLong().
   unknown_fields->AddVarint(1, 0);
-  EXPECT_LT(base_size, empty_message.SpaceUsed());
+  EXPECT_LT(base_size, empty_message.SpaceUsedLong());
-  base_size = empty_message.SpaceUsed();
+  base_size = empty_message.SpaceUsedLong();
 
   std::string* str = unknown_fields->AddLengthDelimited(1);
-  EXPECT_LT(base_size, empty_message.SpaceUsed());
+  EXPECT_LT(base_size, empty_message.SpaceUsedLong());
-  base_size = empty_message.SpaceUsed();
+  base_size = empty_message.SpaceUsedLong();
 
   str->assign(sizeof(std::string) + 1, 'x');
-  EXPECT_LT(base_size, empty_message.SpaceUsed());
+  EXPECT_LT(base_size, empty_message.SpaceUsedLong());
-  base_size = empty_message.SpaceUsed();
+  base_size = empty_message.SpaceUsedLong();
 
   UnknownFieldSet* group = unknown_fields->AddGroup(1);
-  EXPECT_LT(base_size, empty_message.SpaceUsed());
+  EXPECT_LT(base_size, empty_message.SpaceUsedLong());
-  base_size = empty_message.SpaceUsed();
+  base_size = empty_message.SpaceUsedLong();
 
   group->AddVarint(1, 0);
-  EXPECT_LT(base_size, empty_message.SpaceUsed());
+  EXPECT_LT(base_size, empty_message.SpaceUsedLong());
 }
 
 

src/google/protobuf/util/field_mask_util_test.cc

@@ -46,7 +46,7 @@ namespace util {
 
 class SnakeCaseCamelCaseTest : public ::testing::Test {
  protected:
-  string SnakeCaseToCamelCase(const std::string& input) {
+  std::string SnakeCaseToCamelCase(const std::string& input) {
     std::string output;
     if (FieldMaskUtil::SnakeCaseToCamelCase(input, &output)) {
       return output;
@@ -55,7 +55,7 @@ class SnakeCaseCamelCaseTest : public ::testing::Test {
     }
   }
 
-  string CamelCaseToSnakeCase(const std::string& input) {
+  std::string CamelCaseToSnakeCase(const std::string& input) {
     std::string output;
     if (FieldMaskUtil::CamelCaseToSnakeCase(input, &output)) {
       return output;

src/google/protobuf/util/json_util.cc

@@ -145,8 +145,8 @@ class StatusErrorListener : public converter::ErrorListener {
                     StringPiece value) override {
     status_ = util::Status(
         util::error::INVALID_ARGUMENT,
-        StrCat(GetLocString(loc), ": invalid value ", string(value),
+        StrCat(GetLocString(loc), ": invalid value ", std::string(value),
-                     " for type ", string(type_name)));
+                     " for type ", std::string(type_name)));
   }
 
   void MissingField(const converter::LocationTrackerInterface& loc,

src/google/protobuf/util/message_differencer_unittest.cc

@@ -1205,7 +1205,7 @@ TEST(MessageDifferencerTest, RepeatedFieldSmartSetTest_PreviouslyMatch) {
   *msg2.add_rm() = elem1_2;
   *msg2.add_rm() = elem2_2;
 
-  string diff_report;
+  std::string diff_report;
   util::MessageDifferencer differencer;
   differencer.ReportDifferencesToString(&diff_report);
   differencer.set_repeated_field_comparison(
@@ -2385,7 +2385,7 @@ class ComparisonTest : public testing::Test {
 
   void field_as_set(const std::string& field) { set_field_ = field; }
 
-  void field_as_map(const string& field, const std::string& key) {
+  void field_as_map(const std::string& field, const std::string& key) {
     map_field_ = field;
     map_key_ = key;
   }
@@ -3198,11 +3198,13 @@ TEST_F(ComparisonTest, EquivalentIgnoresUnknown) {
 }
 
 TEST_F(ComparisonTest, MapTest) {
-  Map<string, std::string>& map1 = *map_proto1_.mutable_map_string_string();
+  Map<std::string, std::string>& map1 =
+      *map_proto1_.mutable_map_string_string();
   map1["key1"] = "1";
   map1["key2"] = "2";
   map1["key3"] = "3";
-  Map<string, std::string>& map2 = *map_proto2_.mutable_map_string_string();
+  Map<std::string, std::string>& map2 =
+      *map_proto2_.mutable_map_string_string();
   map2["key3"] = "0";
   map2["key2"] = "2";
   map2["key1"] = "1";
@@ -3212,11 +3214,13 @@ TEST_F(ComparisonTest, MapTest) {
 }
 
 TEST_F(ComparisonTest, MapIgnoreKeyTest) {
-  Map<string, std::string>& map1 = *map_proto1_.mutable_map_string_string();
+  Map<std::string, std::string>& map1 =
+      *map_proto1_.mutable_map_string_string();
   map1["key1"] = "1";
   map1["key2"] = "2";
   map1["key3"] = "3";
-  Map<string, std::string>& map2 = *map_proto2_.mutable_map_string_string();
+  Map<std::string, std::string>& map2 =
+      *map_proto2_.mutable_map_string_string();
   map2["key4"] = "2";
   map2["key5"] = "3";
   map2["key6"] = "1";

src/google/protobuf/util/type_resolver_util.cc

@@ -305,7 +305,7 @@ class DescriptorPoolTypeResolver : public TypeResolver {
     return url_prefix_ + "/" + descriptor->full_name();
   }
 
-  Status ParseTypeUrl(const string& type_url, std::string* type_name) {
+  Status ParseTypeUrl(const std::string& type_url, std::string* type_name) {
     if (type_url.substr(0, url_prefix_.size() + 1) != url_prefix_ + "/") {
       return Status(
           util::error::INVALID_ARGUMENT,

src/google/protobuf/util/type_resolver_util_test.cc

@@ -158,7 +158,7 @@ class DescriptorPoolTypeResolverTest : public testing::Test {
     return false;
   }
 
-  string GetTypeUrl(std::string full_name) {
+  std::string GetTypeUrl(std::string full_name) {
     return kUrlPrefix + std::string("/") + full_name;
   }
 

src/google/protobuf/wire_format_unittest.cc

@@ -38,6 +38,7 @@
 #include <google/protobuf/stubs/common.h>
 #include <google/protobuf/stubs/logging.h>
 #include <google/protobuf/test_util.h>
+#include <google/protobuf/test_util2.h>
 #include <google/protobuf/unittest.pb.h>
 #include <google/protobuf/unittest_mset.pb.h>
 #include <google/protobuf/unittest_mset_wire_format.pb.h>
@@ -48,12 +49,15 @@
 #include <google/protobuf/descriptor.h>
 #include <google/protobuf/wire_format_lite.h>
 #include <google/protobuf/testing/googletest.h>
+#include <gmock/gmock.h>
 #include <gtest/gtest.h>
 #include <google/protobuf/stubs/casts.h>
 #include <google/protobuf/stubs/strutil.h>
 #include <google/protobuf/stubs/stl_util.h>
 
+// clang-format off
 #include <google/protobuf/port_def.inc>
+// clang-format on
 
 namespace google {
 namespace protobuf {
@@ -209,8 +213,16 @@ TEST(WireFormatTest, OneofOnlySetLast) {
   source.set_foo_int(100);
   source.set_foo_string("101");
 
-  // Serialize and parse to oneof message.
+  // Serialize and parse to oneof message. Generated serializer may not order
-  source.SerializeToString(&data);
+  // fields in tag order. Use WireFormat::SerializeWithCachedSizes instead as
+  // it sorts fields beforehand.
+  {
+    io::StringOutputStream raw_output(&data);
+    io::CodedOutputStream output(&raw_output);
+    WireFormat::SerializeWithCachedSizes(source, source.ByteSizeLong(),
+                                         &output);
+    ASSERT_FALSE(output.HadError());
+  }
   io::ArrayInputStream raw_input(data.data(), data.size());
   io::CodedInputStream input(&raw_input);
   WireFormat::ParseAndMergePartial(&input, &oneof_dest);
@@ -224,9 +236,9 @@ TEST(WireFormatTest, ByteSize) {
   unittest::TestAllTypes message;
   TestUtil::SetAllFields(&message);
 
-  EXPECT_EQ(message.ByteSize(), WireFormat::ByteSize(message));
+  EXPECT_EQ(message.ByteSizeLong(), WireFormat::ByteSize(message));
   message.Clear();
-  EXPECT_EQ(0, message.ByteSize());
+  EXPECT_EQ(0, message.ByteSizeLong());
   EXPECT_EQ(0, WireFormat::ByteSize(message));
 }
 
@@ -234,9 +246,9 @@ TEST(WireFormatTest, ByteSizeExtensions) {
   unittest::TestAllExtensions message;
   TestUtil::SetAllExtensions(&message);
 
-  EXPECT_EQ(message.ByteSize(), WireFormat::ByteSize(message));
+  EXPECT_EQ(message.ByteSizeLong(), WireFormat::ByteSize(message));
   message.Clear();
-  EXPECT_EQ(0, message.ByteSize());
+  EXPECT_EQ(0, message.ByteSizeLong());
   EXPECT_EQ(0, WireFormat::ByteSize(message));
 }
 
@@ -244,9 +256,9 @@ TEST(WireFormatTest, ByteSizePacked) {
   unittest::TestPackedTypes message;
   TestUtil::SetPackedFields(&message);
 
-  EXPECT_EQ(message.ByteSize(), WireFormat::ByteSize(message));
+  EXPECT_EQ(message.ByteSizeLong(), WireFormat::ByteSize(message));
   message.Clear();
-  EXPECT_EQ(0, message.ByteSize());
+  EXPECT_EQ(0, message.ByteSizeLong());
   EXPECT_EQ(0, WireFormat::ByteSize(message));
 }
 
@@ -254,9 +266,9 @@ TEST(WireFormatTest, ByteSizePackedExtensions) {
   unittest::TestPackedExtensions message;
   TestUtil::SetPackedExtensions(&message);
 
-  EXPECT_EQ(message.ByteSize(), WireFormat::ByteSize(message));
+  EXPECT_EQ(message.ByteSizeLong(), WireFormat::ByteSize(message));
   message.Clear();
-  EXPECT_EQ(0, message.ByteSize());
+  EXPECT_EQ(0, message.ByteSizeLong());
   EXPECT_EQ(0, WireFormat::ByteSize(message));
 }
 
@@ -264,10 +276,10 @@ TEST(WireFormatTest, ByteSizeOneof) {
   unittest::TestOneof2 message;
   TestUtil::SetOneof1(&message);
 
-  EXPECT_EQ(message.ByteSize(), WireFormat::ByteSize(message));
+  EXPECT_EQ(message.ByteSizeLong(), WireFormat::ByteSize(message));
   message.Clear();
 
-  EXPECT_EQ(0, message.ByteSize());
+  EXPECT_EQ(0, message.ByteSizeLong());
   EXPECT_EQ(0, WireFormat::ByteSize(message));
 }
 
@@ -277,7 +289,7 @@ TEST(WireFormatTest, Serialize) {
   std::string dynamic_data;
 
   TestUtil::SetAllFields(&message);
-  int size = message.ByteSize();
+  size_t size = message.ByteSizeLong();
 
   // Serialize using the generated code.
   {
@@ -295,10 +307,9 @@ TEST(WireFormatTest, Serialize) {
     ASSERT_FALSE(output.HadError());
   }
 
-  // Should be the same.
+  // Should parse to the same message.
-  // Don't use EXPECT_EQ here because we're comparing raw binary data and
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, generated_data));
-  // we really don't want it dumped to stdout on failure.
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, dynamic_data));
-  EXPECT_TRUE(dynamic_data == generated_data);
 }
 
 TEST(WireFormatTest, SerializeExtensions) {
@@ -307,7 +318,7 @@ TEST(WireFormatTest, SerializeExtensions) {
   std::string dynamic_data;
 
   TestUtil::SetAllExtensions(&message);
-  int size = message.ByteSize();
+  size_t size = message.ByteSizeLong();
 
   // Serialize using the generated code.
   {
@@ -325,10 +336,9 @@ TEST(WireFormatTest, SerializeExtensions) {
     ASSERT_FALSE(output.HadError());
   }
 
-  // Should be the same.
+  // Should parse to the same message.
-  // Don't use EXPECT_EQ here because we're comparing raw binary data and
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, generated_data));
-  // we really don't want it dumped to stdout on failure.
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, dynamic_data));
-  EXPECT_TRUE(dynamic_data == generated_data);
 }
 
 TEST(WireFormatTest, SerializeFieldsAndExtensions) {
@@ -337,7 +347,7 @@ TEST(WireFormatTest, SerializeFieldsAndExtensions) {
   std::string dynamic_data;
 
   TestUtil::SetAllFieldsAndExtensions(&message);
-  int size = message.ByteSize();
+  size_t size = message.ByteSizeLong();
 
   // Serialize using the generated code.
   {
@@ -355,14 +365,9 @@ TEST(WireFormatTest, SerializeFieldsAndExtensions) {
     ASSERT_FALSE(output.HadError());
   }
 
-  // Should be the same.
+  // Should parse to the same message.
-  // Don't use EXPECT_EQ here because we're comparing raw binary data and
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, generated_data));
-  // we really don't want it dumped to stdout on failure.
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, dynamic_data));
-  EXPECT_TRUE(dynamic_data == generated_data);
-
-  // Should output in canonical order.
-  TestUtil::ExpectAllFieldsAndExtensionsInOrder(dynamic_data);
-  TestUtil::ExpectAllFieldsAndExtensionsInOrder(generated_data);
 }
 
 TEST(WireFormatTest, SerializeOneof) {
@@ -371,7 +376,7 @@ TEST(WireFormatTest, SerializeOneof) {
   std::string dynamic_data;
 
   TestUtil::SetOneof1(&message);
-  int size = message.ByteSize();
+  size_t size = message.ByteSizeLong();
 
   // Serialize using the generated code.
   {
@@ -389,10 +394,9 @@ TEST(WireFormatTest, SerializeOneof) {
     ASSERT_FALSE(output.HadError());
   }
 
-  // Should be the same.
+  // Should parse to the same message.
-  // Don't use EXPECT_EQ here because we're comparing raw binary data and
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, generated_data));
-  // we really don't want it dumped to stdout on failure.
+  EXPECT_TRUE(TestUtil::EqualsToSerialized(message, dynamic_data));
-  EXPECT_TRUE(dynamic_data == generated_data);
 }
 
 TEST(WireFormatTest, ParseMultipleExtensionRanges) {
@@ -482,7 +486,7 @@ TEST(WireFormatTest, SerializeMessageSetVariousWaysAreEqual) {
   message_set.mutable_unknown_fields()->AddLengthDelimited(kUnknownTypeId,
                                                            "bar");
 
-  int size = message_set.ByteSize();
+  size_t size = message_set.ByteSizeLong();
   EXPECT_EQ(size, message_set.GetCachedSize());
   ASSERT_EQ(size, WireFormat::ByteSize(message_set));
 
@@ -595,7 +599,7 @@ TEST(WireFormatTest, ParseMessageSetWithReverseTagOrder) {
     WireFormatLite::WriteTag(WireFormatLite::kMessageSetMessageNumber,
                              WireFormatLite::WIRETYPE_LENGTH_DELIMITED,
                              &coded_output);
-    coded_output.WriteVarint32(message.ByteSize());
+    coded_output.WriteVarint32(message.ByteSizeLong());
     message.SerializeWithCachedSizes(&coded_output);
     // Write the type id.
     uint32 type_id = message.GetDescriptor()->extension(0)->number();
@@ -989,7 +993,7 @@ class Proto3PrimitiveRepeatedWireFormatTest : public ::testing::Test {
   void TestSerialization(Proto* message, const std::string& expected) {
     SetProto3PrimitiveRepeatedFields(message);
 
-    int size = message->ByteSize();
+    size_t size = message->ByteSizeLong();
 
     // Serialize using the generated code.
     std::string generated_data;
@@ -999,7 +1003,7 @@ class Proto3PrimitiveRepeatedWireFormatTest : public ::testing::Test {
       message->SerializeWithCachedSizes(&output);
       ASSERT_FALSE(output.HadError());
     }
-    EXPECT_TRUE(expected == generated_data);
+    EXPECT_TRUE(TestUtil::EqualsToSerialized(*message, generated_data));
 
     // Serialize using the dynamic code.
     std::string dynamic_data;