Refactor weak repeated message field code in order to support split repeated fields.

- Make WeakRepeatedPtrField arena constructible/destructor skippable.
- Add _internal_weak_$name$()/_internal_mutable_weak_$name$().

PiperOrigin-RevId: 530402675

src/google/protobuf/compiler/cpp/field_generators/message_field.cc

@@ -734,11 +734,7 @@ class RepeatedMessage : public FieldGeneratorBase {
 };
 
 void RepeatedMessage::GeneratePrivateMembers(io::Printer* p) const {
-  if (weak_) {
-    p->Emit("$pb$::WeakRepeatedPtrField< $Submsg$ > $name$_;\n");
-  } else {
-    p->Emit("$pb$::RepeatedPtrField< $Submsg$ > $name$_;\n");
-  }
+  p->Emit("$pb$::$Weak$RepeatedPtrField< $Submsg$ > $name$_;\n");
 }
 
 void RepeatedMessage::GenerateAccessorDeclarations(io::Printer* p) const {
@@ -752,10 +748,18 @@ void RepeatedMessage::GenerateAccessorDeclarations(io::Printer* p) const {
   format(
       "private:\n"
       "const $pb$::RepeatedPtrField<$Submsg$>& _internal_$name$() const;\n"
-      "$pb$::RepeatedPtrField<$Submsg$>* _internal_mutable_$name$();\n"
-      "public:\n");
-  format("$DEPRECATED$ const $Submsg$& ${1$$name$$}$(int index) const;\n",
-         field_);
+      "$pb$::RepeatedPtrField<$Submsg$>* _internal_mutable_$name$();\n");
+  if (weak_) {
+    format(
+        "const $pb$::WeakRepeatedPtrField<$Submsg$>& _internal_weak_$name$() "
+        "const;\n"
+        "$pb$::WeakRepeatedPtrField<$Submsg$>* "
+        "_internal_mutable_weak_$name$();\n");
+  }
+  format(
+      "public:\n"
+      "$DEPRECATED$ const $Submsg$& ${1$$name$$}$(int index) const;\n",
+      field_);
   format("$DEPRECATED$ $Submsg$* ${1$add_$name$$}$();\n",
          std::make_tuple(field_, GeneratedCodeInfo::Annotation::SET));
   format(
@@ -810,15 +814,28 @@ void RepeatedMessage::GenerateInlineAccessorDefinitions(io::Printer* p) const {
       "  return _internal_$name$();\n"
       "}\n");
 
-  p->Emit(
-      "inline const $pb$::RepeatedPtrField<$Submsg$>&\n"
-      "$classname$::_internal_$name$() const {\n"
-      "  return $field$$.weak$;\n"
-      "}\n"
-      "inline $pb$::RepeatedPtrField<$Submsg$>*\n"
-      "$classname$::_internal_mutable_$name$() {\n"
-      "  return &$field$$.weak$;\n"
-      "}\n");
+  p->Emit(R"cc(
+    inline const $pb$::RepeatedPtrField<$Submsg$>&
+    $classname$::_internal_$name$() const {
+      return $field$$.weak$;
+    }
+    inline $pb$::RepeatedPtrField<$Submsg$>*
+    $classname$::_internal_mutable_$name$() {
+      return &$field$$.weak$;
+    }
+  )cc");
+  if (weak_) {
+    p->Emit(R"cc(
+      inline const $pb$::WeakRepeatedPtrField<$Submsg$>&
+      $Msg$::_internal_weak_$name$() const {
+        return $field$;
+      }
+      inline $pb$::WeakRepeatedPtrField<$Submsg$>*
+      $Msg$::_internal_mutable_weak_$name$() {
+        return &$field$;
+      }
+    )cc");
+  }
 }
 
 void RepeatedMessage::GenerateClearingCode(io::Printer* p) const {
@@ -831,7 +848,9 @@ void RepeatedMessage::GenerateClearingCode(io::Printer* p) const {
 
 void RepeatedMessage::GenerateMergingCode(io::Printer* p) const {
   if (weak_) {
-    p->Emit("_this->$field_$.MergeFrom(from.$field_$);\n");
+    p->Emit(
+        "_this->_internal_mutable_weak_$name$()->MergeFrom(from._internal_weak_"
+        "$name$());\n");
   } else {
     p->Emit(
         "_this->_internal_mutable_$name$()->MergeFrom("
@@ -841,7 +860,9 @@ void RepeatedMessage::GenerateMergingCode(io::Printer* p) const {
 
 void RepeatedMessage::GenerateSwappingCode(io::Printer* p) const {
   if (weak_) {
-    p->Emit("$field_$.InternalSwap(&other->$field_$);\n");
+    p->Emit(
+        "_internal_mutable_weak_$name$()->InternalSwap(other->_internal_"
+        "mutable_weak_$name$());\n");
   } else {
     p->Emit(
         "_internal_mutable_$name$()->InternalSwap(other->_internal_mutable_"
@@ -854,11 +875,7 @@ void RepeatedMessage::GenerateConstructorCode(io::Printer* p) const {
 }
 
 void RepeatedMessage::GenerateDestructorCode(io::Printer* p) const {
-  if (weak_) {
-    p->Emit("$field_$.~WeakRepeatedPtrField();\n");
-  } else {
-    p->Emit("_internal_mutable_$name$()->~RepeatedPtrField();\n");
-  }
+  p->Emit("$field_$.~$Weak$RepeatedPtrField();\n");
 }
 
 void RepeatedMessage::GenerateSerializeWithCachedSizesToArray(

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

@@ -706,7 +706,7 @@ CodeGeneratorRequest::~CodeGeneratorRequest() {
 inline void CodeGeneratorRequest::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _internal_mutable_file_to_generate()->~RepeatedPtrField();
-  _internal_mutable_proto_file()->~RepeatedPtrField();
+  _impl_.proto_file_.~RepeatedPtrField();
   _impl_.parameter_.Destroy();
   if (this != internal_default_instance()) delete _impl_.compiler_version_;
 }
@@ -1422,7 +1422,7 @@ CodeGeneratorResponse::~CodeGeneratorResponse() {
 
 inline void CodeGeneratorResponse::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
-  _internal_mutable_file()->~RepeatedPtrField();
+  _impl_.file_.~RepeatedPtrField();
   _impl_.error_.Destroy();
 }
 

src/google/protobuf/descriptor.pb.cc

@@ -1875,7 +1875,7 @@ FileDescriptorSet::~FileDescriptorSet() {
 
 inline void FileDescriptorSet::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
-  _internal_mutable_file()->~RepeatedPtrField();
+  _impl_.file_.~RepeatedPtrField();
 }
 
 void FileDescriptorSet::SetCachedSize(int size) const {
@@ -2177,10 +2177,10 @@ FileDescriptorProto::~FileDescriptorProto() {
 inline void FileDescriptorProto::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _internal_mutable_dependency()->~RepeatedPtrField();
-  _internal_mutable_message_type()->~RepeatedPtrField();
-  _internal_mutable_enum_type()->~RepeatedPtrField();
-  _internal_mutable_service()->~RepeatedPtrField();
-  _internal_mutable_extension()->~RepeatedPtrField();
+  _impl_.message_type_.~RepeatedPtrField();
+  _impl_.enum_type_.~RepeatedPtrField();
+  _impl_.service_.~RepeatedPtrField();
+  _impl_.extension_.~RepeatedPtrField();
   _impl_.public_dependency_.~RepeatedField();
   _impl_.weak_dependency_.~RepeatedField();
   _impl_.name_.Destroy();
@@ -3389,13 +3389,13 @@ DescriptorProto::~DescriptorProto() {
 
 inline void DescriptorProto::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
-  _internal_mutable_field()->~RepeatedPtrField();
-  _internal_mutable_nested_type()->~RepeatedPtrField();
-  _internal_mutable_enum_type()->~RepeatedPtrField();
-  _internal_mutable_extension_range()->~RepeatedPtrField();
-  _internal_mutable_extension()->~RepeatedPtrField();
-  _internal_mutable_oneof_decl()->~RepeatedPtrField();
-  _internal_mutable_reserved_range()->~RepeatedPtrField();
+  _impl_.field_.~RepeatedPtrField();
+  _impl_.nested_type_.~RepeatedPtrField();
+  _impl_.enum_type_.~RepeatedPtrField();
+  _impl_.extension_range_.~RepeatedPtrField();
+  _impl_.extension_.~RepeatedPtrField();
+  _impl_.oneof_decl_.~RepeatedPtrField();
+  _impl_.reserved_range_.~RepeatedPtrField();
   _internal_mutable_reserved_name()->~RepeatedPtrField();
   _impl_.name_.Destroy();
   if (this != internal_default_instance()) delete _impl_.options_;
@@ -4346,8 +4346,8 @@ ExtensionRangeOptions::~ExtensionRangeOptions() {
 inline void ExtensionRangeOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
-  _internal_mutable_declaration()->~RepeatedPtrField();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.declaration_.~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
 }
 
 void ExtensionRangeOptions::SetCachedSize(int size) const {
@@ -5844,8 +5844,8 @@ EnumDescriptorProto::~EnumDescriptorProto() {
 
 inline void EnumDescriptorProto::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
-  _internal_mutable_value()->~RepeatedPtrField();
-  _internal_mutable_reserved_range()->~RepeatedPtrField();
+  _impl_.value_.~RepeatedPtrField();
+  _impl_.reserved_range_.~RepeatedPtrField();
   _internal_mutable_reserved_name()->~RepeatedPtrField();
   _impl_.name_.Destroy();
   if (this != internal_default_instance()) delete _impl_.options_;
@@ -6533,7 +6533,7 @@ ServiceDescriptorProto::~ServiceDescriptorProto() {
 
 inline void ServiceDescriptorProto::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
-  _internal_mutable_method()->~RepeatedPtrField();
+  _impl_.method_.~RepeatedPtrField();
   _impl_.name_.Destroy();
   if (this != internal_default_instance()) delete _impl_.options_;
 }
@@ -7521,7 +7521,7 @@ FileOptions::~FileOptions() {
 inline void FileOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
   _impl_.java_package_.Destroy();
   _impl_.java_outer_classname_.Destroy();
   _impl_.go_package_.Destroy();
@@ -8431,7 +8431,7 @@ MessageOptions::~MessageOptions() {
 inline void MessageOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
 }
 
 void MessageOptions::SetCachedSize(int size) const {
@@ -8869,7 +8869,7 @@ inline void FieldOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
   _internal_mutable_targets()->~RepeatedField();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
 }
 
 void FieldOptions::SetCachedSize(int size) const {
@@ -9426,7 +9426,7 @@ OneofOptions::~OneofOptions() {
 inline void OneofOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
 }
 
 void OneofOptions::SetCachedSize(int size) const {
@@ -9661,7 +9661,7 @@ EnumOptions::~EnumOptions() {
 inline void EnumOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
 }
 
 void EnumOptions::SetCachedSize(int size) const {
@@ -9976,7 +9976,7 @@ EnumValueOptions::~EnumValueOptions() {
 inline void EnumValueOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
 }
 
 void EnumValueOptions::SetCachedSize(int size) const {
@@ -10228,7 +10228,7 @@ ServiceOptions::~ServiceOptions() {
 inline void ServiceOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
 }
 
 void ServiceOptions::SetCachedSize(int size) const {
@@ -10489,7 +10489,7 @@ MethodOptions::~MethodOptions() {
 inline void MethodOptions::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
   _impl_._extensions_.~ExtensionSet();
-  _internal_mutable_uninterpreted_option()->~RepeatedPtrField();
+  _impl_.uninterpreted_option_.~RepeatedPtrField();
 }
 
 void MethodOptions::SetCachedSize(int size) const {
@@ -11127,7 +11127,7 @@ UninterpretedOption::~UninterpretedOption() {
 
 inline void UninterpretedOption::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
-  _internal_mutable_name()->~RepeatedPtrField();
+  _impl_.name_.~RepeatedPtrField();
   _impl_.identifier_value_.Destroy();
   _impl_.string_value_.Destroy();
   _impl_.aggregate_value_.Destroy();
@@ -11925,7 +11925,7 @@ SourceCodeInfo::~SourceCodeInfo() {
 
 inline void SourceCodeInfo::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
-  _internal_mutable_location()->~RepeatedPtrField();
+  _impl_.location_.~RepeatedPtrField();
 }
 
 void SourceCodeInfo::SetCachedSize(int size) const {
@@ -12490,7 +12490,7 @@ GeneratedCodeInfo::~GeneratedCodeInfo() {
 
 inline void GeneratedCodeInfo::SharedDtor() {
   ABSL_DCHECK(GetArenaForAllocation() == nullptr);
-  _internal_mutable_annotation()->~RepeatedPtrField();
+  _impl_.annotation_.~RepeatedPtrField();
 }
 
 void GeneratedCodeInfo::SetCachedSize(int size) const {

src/google/protobuf/implicit_weak_message.h

@@ -152,6 +152,9 @@ class ImplicitWeakTypeHandler {
 
 template <typename T>
 struct WeakRepeatedPtrField {
+  using InternalArenaConstructable_ = void;
+  using DestructorSkippable_ = void;
+
   using TypeHandler = internal::ImplicitWeakTypeHandler<T>;
   constexpr WeakRepeatedPtrField() : weak() {}
   explicit WeakRepeatedPtrField(Arena* arena) : weak(arena) {}