Fix toproto behavior for groups and required under editions

PiperOrigin-RevId: 619359463

upb/util/BUILD

@@ -18,6 +18,8 @@ cc_library(
     hdrs = ["def_to_proto.h"],
     visibility = ["//visibility:public"],
     deps = [
+        "//upb:base",
+        "//upb:descriptor_upb_proto",
         "//upb:port",
         "//upb:reflection",
         "//upb/reflection:internal",
@@ -64,11 +66,15 @@ cc_test(
     srcs = ["def_to_proto_test.cc"],
     deps = [
         ":def_to_proto",
+        ":def_to_proto_editions_test_upb_proto",
+        ":def_to_proto_editions_test_upb_proto_reflection",
         ":def_to_proto_test_lib",
         ":def_to_proto_test_upb_proto",
         ":def_to_proto_test_upb_proto_reflection",
         "//:protobuf",
         "//src/google/protobuf/util:differencer",
+        "//upb:base",
+        "//upb:descriptor_upb_proto",
         "//upb:descriptor_upb_proto_reflection",
         "//upb:mem",
         "//upb:reflection",
@@ -108,6 +114,21 @@ cc_library(
     ],
 )
 
+proto_library(
+    name = "def_to_proto_editions_test_proto",
+    srcs = ["def_to_proto_editions_test.proto"],
+)
+
+upb_c_proto_library(
+    name = "def_to_proto_editions_test_upb_proto",
+    deps = ["def_to_proto_editions_test_proto"],
+)
+
+upb_proto_reflection_library(
+    name = "def_to_proto_editions_test_upb_proto_reflection",
+    deps = ["def_to_proto_editions_test_proto"],
+)
+
 proto_library(
     name = "required_fields_test_proto",
     srcs = [

upb/util/def_to_proto.c

@@ -10,7 +10,10 @@
 #include <inttypes.h>
 #include <math.h>
 
+#include "google/protobuf/descriptor.upb.h"
+#include "upb/base/descriptor_constants.h"
 #include "upb/port/vsnprintf_compat.h"
+#include "upb/reflection/def.h"
 #include "upb/reflection/enum_reserved_range.h"
 #include "upb/reflection/extension_range.h"
 #include "upb/reflection/internal/field_def.h"
@@ -218,8 +221,20 @@ static google_protobuf_FieldDescriptorProto* fielddef_toproto(upb_ToProto_Contex
   google_protobuf_FieldDescriptorProto_set_name(proto,
                                        strviewdup(ctx, upb_FieldDef_Name(f)));
   google_protobuf_FieldDescriptorProto_set_number(proto, upb_FieldDef_Number(f));
-  google_protobuf_FieldDescriptorProto_set_label(proto, upb_FieldDef_Label(f));
-  google_protobuf_FieldDescriptorProto_set_type(proto, upb_FieldDef_Type(f));
+
+  if (upb_FieldDef_IsRequired(f) &&
+      upb_FileDef_Edition(upb_FieldDef_File(f)) >= UPB_DESC(EDITION_2023)) {
+    google_protobuf_FieldDescriptorProto_set_label(
+        proto, UPB_DESC(FieldDescriptorProto_LABEL_OPTIONAL));
+  } else {
+    google_protobuf_FieldDescriptorProto_set_label(proto, upb_FieldDef_Label(f));
+  }
+  if (upb_FieldDef_Type(f) == kUpb_FieldType_Group &&
+      upb_FileDef_Edition(upb_FieldDef_File(f)) >= UPB_DESC(EDITION_2023)) {
+    google_protobuf_FieldDescriptorProto_set_type(proto, kUpb_FieldType_Message);
+  } else {
+    google_protobuf_FieldDescriptorProto_set_type(proto, upb_FieldDef_Type(f));
+  }
 
   if (upb_FieldDef_HasJsonName(f)) {
     google_protobuf_FieldDescriptorProto_set_json_name(

upb/util/def_to_proto_editions_test.proto

@@ -0,0 +1,8 @@
+edition = "2023";
+
+package pkg;
+
+message EditionsMessage {
+  int32 required_field = 1 [features.field_presence = LEGACY_REQUIRED];
+  EditionsMessage delimited_field = 2 [features.message_encoding = DELIMITED];
+}

upb/util/def_to_proto_test.cc

@@ -7,18 +7,22 @@
 
 #include "upb/util/def_to_proto.h"
 
+#include <cstddef>
 #include <memory>
 #include <string>
 
 #include "google/protobuf/descriptor.pb.h"
+#include "google/protobuf/descriptor.upb.h"
 #include "google/protobuf/descriptor.upbdefs.h"
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 #include "google/protobuf/dynamic_message.h"
 #include "google/protobuf/util/message_differencer.h"
+#include "upb/base/string_view.h"
 #include "upb/mem/arena.hpp"
 #include "upb/reflection/def.hpp"
 #include "upb/test/parse_text_proto.h"
+#include "upb/util/def_to_proto_editions_test.upbdefs.h"
 #include "upb/util/def_to_proto_test.h"
 #include "upb/util/def_to_proto_test.upbdefs.h"
 
@@ -115,6 +119,29 @@ TEST(DefToProto, Test) {
   CheckFile(file, file_desc);
 }
 
+// Verifies that editions don't leak out legacy feature APIs (e.g. TYPE_GROUP
+// and LABEL_REQUIRED):
+//   serialized descriptor -> upb def -> serialized descriptor
+TEST(DefToProto, TestEditionsLegacyFeatures) {
+  upb::Arena arena;
+  upb::DefPool defpool;
+  upb_StringView test_file_desc =
+      upb_util_def_to_proto_editions_test_proto_upbdefinit
+          .descriptor;
+  const auto* file = google_protobuf_FileDescriptorProto_parse(
+      test_file_desc.data, test_file_desc.size, arena.ptr());
+
+  size_t size;
+  const auto* messages = google_protobuf_FileDescriptorProto_message_type(file, &size);
+  ASSERT_EQ(size, 1);
+  const auto* fields = google_protobuf_DescriptorProto_field(messages[0], &size);
+  ASSERT_EQ(size, 2);
+  EXPECT_EQ(google_protobuf_FieldDescriptorProto_label(fields[0]),
+            google_protobuf_FieldDescriptorProto_LABEL_OPTIONAL);
+  EXPECT_EQ(google_protobuf_FieldDescriptorProto_type(fields[1]),
+            google_protobuf_FieldDescriptorProto_TYPE_MESSAGE);
+}
+
 // Like the previous test, but uses a message layout built at runtime.
 TEST(DefToProto, TestRuntimeReflection) {
   upb::Arena arena;