all: update to protobuf-v3.9.1 and go-v1.11.13 and go-v1.12.9

A conformance test has been added for the text format.
Update our conformance runner to handle that format and
update with the list of current failures.

Change-Id: I36a271fcfbe328c4ee8c870caff4661659ad27ef
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/190517
Reviewed-by: Herbie Ong <herbie@google.com>
diff --git a/integration_test.go b/integration_test.go
index cc06bd8..ffe4b84 100644
--- a/integration_test.go
+++ b/integration_test.go
@@ -30,8 +30,8 @@
 var (
 	regenerate = flag.Bool("regenerate", false, "regenerate files")
 
-	protobufVersion = "3.7.1"
-	golangVersions  = []string{"1.9.7", "1.10.8", "1.11.6", "1.12.1"}
+	protobufVersion = "3.9.1"
+	golangVersions  = []string{"1.9.7", "1.10.8", "1.11.13", "1.12.9"}
 	golangLatest    = golangVersions[len(golangVersions)-1]
 
 	// purgeTimeout determines the maximum age of unused sub-directories.
@@ -89,9 +89,10 @@
 	t.Run("ConformanceTests", func(t *testing.T) {
 		driverPath := filepath.Join("internal", "cmd", "conformance")
 		driver := filepath.Join(driverPath, "conformance.sh")
-		failureList := filepath.Join(driverPath, "failure_list_go.txt")
+		failureList := filepath.Join(driverPath, "failure_list.txt")
+		textFailureList := filepath.Join(driverPath, "text_failure_list.txt")
 		runner := filepath.Join(protobufPath, "conformance", "conformance-test-runner")
-		mustRunCommand(t, runner, "--failure_list", failureList, "--enforce_recommended", driver)
+		mustRunCommand(t, runner, "--failure_list", failureList, "--text_format_failure_list", textFailureList, "--enforce_recommended", driver)
 	})
 	t.Run("GeneratedGoFiles", func(t *testing.T) {
 		diff := mustRunCommand(t, "go", "run", "-tags", "protolegacy", "./internal/cmd/generate-types")
diff --git a/internal/cmd/conformance/failure_list_go.txt b/internal/cmd/conformance/failure_list.txt
similarity index 100%
rename from internal/cmd/conformance/failure_list_go.txt
rename to internal/cmd/conformance/failure_list.txt
diff --git a/internal/cmd/conformance/main.go b/internal/cmd/conformance/main.go
index ea54a82..74286c3 100644
--- a/internal/cmd/conformance/main.go
+++ b/internal/cmd/conformance/main.go
@@ -13,6 +13,7 @@
 	"os"
 
 	"google.golang.org/protobuf/encoding/protojson"
+	"google.golang.org/protobuf/encoding/prototext"
 	"google.golang.org/protobuf/proto"
 
 	pb "google.golang.org/protobuf/internal/testprotos/conformance"
@@ -58,13 +59,14 @@
 	}
 }
 
-func handle(req *pb.ConformanceRequest) *pb.ConformanceResponse {
-	var err error
+func handle(req *pb.ConformanceRequest) (res *pb.ConformanceResponse) {
 	var msg proto.Message = &pb.TestAllTypesProto2{}
 	if req.GetMessageType() == "protobuf_test_messages.proto3.TestAllTypesProto3" {
 		msg = &pb.TestAllTypesProto3{}
 	}
 
+	// Unmarshal the test message.
+	var err error
 	switch p := req.Payload.(type) {
 	case *pb.ConformanceRequest_ProtobufPayload:
 		err = proto.Unmarshal(p.ProtobufPayload, msg)
@@ -72,6 +74,8 @@
 		err = protojson.UnmarshalOptions{
 			DiscardUnknown: req.TestCategory == pb.TestCategory_JSON_IGNORE_UNKNOWN_PARSING_TEST,
 		}.Unmarshal([]byte(p.JsonPayload), msg)
+	case *pb.ConformanceRequest_TextPayload:
+		err = prototext.Unmarshal([]byte(p.TextPayload), msg)
 	default:
 		return &pb.ConformanceResponse{
 			Result: &pb.ConformanceResponse_RuntimeError{
@@ -87,33 +91,28 @@
 		}
 	}
 
+	// Marshal the test message.
+	var b []byte
 	switch req.RequestedOutputFormat {
 	case pb.WireFormat_PROTOBUF:
-		p, err := proto.Marshal(msg)
-		if err != nil {
-			return &pb.ConformanceResponse{
-				Result: &pb.ConformanceResponse_SerializeError{
-					SerializeError: err.Error(),
-				},
-			}
-		}
-		return &pb.ConformanceResponse{
+		b, err = proto.Marshal(msg)
+		res = &pb.ConformanceResponse{
 			Result: &pb.ConformanceResponse_ProtobufPayload{
-				ProtobufPayload: p,
+				ProtobufPayload: b,
 			},
 		}
 	case pb.WireFormat_JSON:
-		p, err := protojson.Marshal(msg)
-		if err != nil {
-			return &pb.ConformanceResponse{
-				Result: &pb.ConformanceResponse_SerializeError{
-					SerializeError: err.Error(),
-				},
-			}
-		}
-		return &pb.ConformanceResponse{
+		b, err = protojson.Marshal(msg)
+		res = &pb.ConformanceResponse{
 			Result: &pb.ConformanceResponse_JsonPayload{
-				JsonPayload: string(p),
+				JsonPayload: string(b),
+			},
+		}
+	case pb.WireFormat_TEXT_FORMAT:
+		b, err = prototext.Marshal(msg)
+		res = &pb.ConformanceResponse{
+			Result: &pb.ConformanceResponse_TextPayload{
+				TextPayload: string(b),
 			},
 		}
 	default:
@@ -123,4 +122,12 @@
 			},
 		}
 	}
+	if err != nil {
+		return &pb.ConformanceResponse{
+			Result: &pb.ConformanceResponse_SerializeError{
+				SerializeError: err.Error(),
+			},
+		}
+	}
+	return res
 }
diff --git a/internal/cmd/conformance/text_failure_list.txt b/internal/cmd/conformance/text_failure_list.txt
new file mode 100644
index 0000000..4ca6f51
--- /dev/null
+++ b/internal/cmd/conformance/text_failure_list.txt
@@ -0,0 +1,13 @@
+Recommended.Proto3.ProtobufInput.GroupUnknownFields_Drop.TextFormatOutput
+Recommended.Proto3.ProtobufInput.MessageUnknownFields_Drop.TextFormatOutput
+Recommended.Proto3.ProtobufInput.MessageUnknownFields_Print.TextFormatOutput
+Recommended.Proto3.ProtobufInput.RepeatedUnknownFields_Drop.TextFormatOutput
+Recommended.Proto3.ProtobufInput.ScalarUnknownFields_Drop.TextFormatOutput
+Required.Proto3.TextFormatInput.FloatFieldLargerThanUint64.ProtobufOutput
+Required.Proto3.TextFormatInput.FloatFieldLargerThanUint64.TextFormatOutput
+Required.Proto3.TextFormatInput.FloatFieldMaxValue.ProtobufOutput
+Required.Proto3.TextFormatInput.FloatFieldMaxValue.TextFormatOutput
+Required.Proto3.TextFormatInput.FloatFieldNaNValue.ProtobufOutput
+Required.Proto3.TextFormatInput.FloatFieldNaNValue.TextFormatOutput
+Required.Proto3.TextFormatInput.FloatFieldTooLarge.ProtobufOutput
+Required.Proto3.TextFormatInput.FloatFieldTooLarge.TextFormatOutput
diff --git a/internal/testprotos/conformance/conformance.pb.go b/internal/testprotos/conformance/conformance.pb.go
index 020b87c..d4e89c7 100644
--- a/internal/testprotos/conformance/conformance.pb.go
+++ b/internal/testprotos/conformance/conformance.pb.go
@@ -242,6 +242,9 @@
 	TestCategory TestCategory `protobuf:"varint,5,opt,name=test_category,json=testCategory,proto3,enum=conformance.TestCategory" json:"test_category,omitempty"`
 	// Specify details for how to encode jspb.
 	JspbEncodingOptions *JspbEncodingConfig `protobuf:"bytes,6,opt,name=jspb_encoding_options,json=jspbEncodingOptions,proto3" json:"jspb_encoding_options,omitempty"`
+	// This can be used in json and text format. If true, testee should print
+	// unknown fields instead of ignore. This feature is optional.
+	PrintUnknownFields bool `protobuf:"varint,9,opt,name=print_unknown_fields,json=printUnknownFields,proto3" json:"print_unknown_fields,omitempty"`
 }
 
 func (x *ConformanceRequest) Reset() {
@@ -334,6 +337,13 @@
 	return nil
 }
 
+func (x *ConformanceRequest) GetPrintUnknownFields() bool {
+	if x != nil {
+		return x.PrintUnknownFields
+	}
+	return false
+}
+
 type isConformanceRequest_Payload interface {
 	isConformanceRequest_Payload()
 }
@@ -597,7 +607,7 @@
 	0x0b, 0x63, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x6e, 0x63, 0x65, 0x22, 0x26, 0x0a, 0x0a,
 	0x46, 0x61, 0x69, 0x6c, 0x75, 0x72, 0x65, 0x53, 0x65, 0x74, 0x12, 0x18, 0x0a, 0x07, 0x66, 0x61,
 	0x69, 0x6c, 0x75, 0x72, 0x65, 0x18, 0x01, 0x20, 0x03, 0x28, 0x09, 0x52, 0x07, 0x66, 0x61, 0x69,
-	0x6c, 0x75, 0x72, 0x65, 0x22, 0xc4, 0x03, 0x0a, 0x12, 0x43, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d,
+	0x6c, 0x75, 0x72, 0x65, 0x22, 0xf6, 0x03, 0x0a, 0x12, 0x43, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d,
 	0x61, 0x6e, 0x63, 0x65, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x12, 0x2b, 0x0a, 0x10, 0x70,
 	0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x5f, 0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18,
 	0x01, 0x20, 0x01, 0x28, 0x0c, 0x48, 0x00, 0x52, 0x0f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75,
@@ -625,54 +635,57 @@
 	0x66, 0x6f, 0x72, 0x6d, 0x61, 0x6e, 0x63, 0x65, 0x2e, 0x4a, 0x73, 0x70, 0x62, 0x45, 0x6e, 0x63,
 	0x6f, 0x64, 0x69, 0x6e, 0x67, 0x43, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x52, 0x13, 0x6a, 0x73, 0x70,
 	0x62, 0x45, 0x6e, 0x63, 0x6f, 0x64, 0x69, 0x6e, 0x67, 0x4f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x73,
-	0x42, 0x09, 0x0a, 0x07, 0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x22, 0xcc, 0x02, 0x0a, 0x13,
-	0x43, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x6e, 0x63, 0x65, 0x52, 0x65, 0x73, 0x70, 0x6f,
-	0x6e, 0x73, 0x65, 0x12, 0x21, 0x0a, 0x0b, 0x70, 0x61, 0x72, 0x73, 0x65, 0x5f, 0x65, 0x72, 0x72,
-	0x6f, 0x72, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52, 0x0a, 0x70, 0x61, 0x72, 0x73,
-	0x65, 0x45, 0x72, 0x72, 0x6f, 0x72, 0x12, 0x29, 0x0a, 0x0f, 0x73, 0x65, 0x72, 0x69, 0x61, 0x6c,
-	0x69, 0x7a, 0x65, 0x5f, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x18, 0x06, 0x20, 0x01, 0x28, 0x09, 0x48,
-	0x00, 0x52, 0x0e, 0x73, 0x65, 0x72, 0x69, 0x61, 0x6c, 0x69, 0x7a, 0x65, 0x45, 0x72, 0x72, 0x6f,
-	0x72, 0x12, 0x25, 0x0a, 0x0d, 0x72, 0x75, 0x6e, 0x74, 0x69, 0x6d, 0x65, 0x5f, 0x65, 0x72, 0x72,
-	0x6f, 0x72, 0x18, 0x02, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52, 0x0c, 0x72, 0x75, 0x6e, 0x74,
-	0x69, 0x6d, 0x65, 0x45, 0x72, 0x72, 0x6f, 0x72, 0x12, 0x2b, 0x0a, 0x10, 0x70, 0x72, 0x6f, 0x74,
-	0x6f, 0x62, 0x75, 0x66, 0x5f, 0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18, 0x03, 0x20, 0x01,
-	0x28, 0x0c, 0x48, 0x00, 0x52, 0x0f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x50, 0x61,
-	0x79, 0x6c, 0x6f, 0x61, 0x64, 0x12, 0x23, 0x0a, 0x0c, 0x6a, 0x73, 0x6f, 0x6e, 0x5f, 0x70, 0x61,
-	0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18, 0x04, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52, 0x0b, 0x6a,
-	0x73, 0x6f, 0x6e, 0x50, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x12, 0x1a, 0x0a, 0x07, 0x73, 0x6b,
-	0x69, 0x70, 0x70, 0x65, 0x64, 0x18, 0x05, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52, 0x07, 0x73,
-	0x6b, 0x69, 0x70, 0x70, 0x65, 0x64, 0x12, 0x23, 0x0a, 0x0c, 0x6a, 0x73, 0x70, 0x62, 0x5f, 0x70,
-	0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18, 0x07, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52, 0x0b,
-	0x6a, 0x73, 0x70, 0x62, 0x50, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x12, 0x23, 0x0a, 0x0c, 0x74,
-	0x65, 0x78, 0x74, 0x5f, 0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18, 0x08, 0x20, 0x01, 0x28,
-	0x09, 0x48, 0x00, 0x52, 0x0b, 0x74, 0x65, 0x78, 0x74, 0x50, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64,
-	0x42, 0x08, 0x0a, 0x06, 0x72, 0x65, 0x73, 0x75, 0x6c, 0x74, 0x22, 0x4e, 0x0a, 0x12, 0x4a, 0x73,
-	0x70, 0x62, 0x45, 0x6e, 0x63, 0x6f, 0x64, 0x69, 0x6e, 0x67, 0x43, 0x6f, 0x6e, 0x66, 0x69, 0x67,
-	0x12, 0x38, 0x0a, 0x19, 0x75, 0x73, 0x65, 0x5f, 0x6a, 0x73, 0x70, 0x62, 0x5f, 0x61, 0x72, 0x72,
-	0x61, 0x79, 0x5f, 0x61, 0x6e, 0x79, 0x5f, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x18, 0x01, 0x20,
-	0x01, 0x28, 0x08, 0x52, 0x15, 0x75, 0x73, 0x65, 0x4a, 0x73, 0x70, 0x62, 0x41, 0x72, 0x72, 0x61,
-	0x79, 0x41, 0x6e, 0x79, 0x46, 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x2a, 0x50, 0x0a, 0x0a, 0x57, 0x69,
-	0x72, 0x65, 0x46, 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x12, 0x0f, 0x0a, 0x0b, 0x55, 0x4e, 0x53, 0x50,
-	0x45, 0x43, 0x49, 0x46, 0x49, 0x45, 0x44, 0x10, 0x00, 0x12, 0x0c, 0x0a, 0x08, 0x50, 0x52, 0x4f,
-	0x54, 0x4f, 0x42, 0x55, 0x46, 0x10, 0x01, 0x12, 0x08, 0x0a, 0x04, 0x4a, 0x53, 0x4f, 0x4e, 0x10,
-	0x02, 0x12, 0x08, 0x0a, 0x04, 0x4a, 0x53, 0x50, 0x42, 0x10, 0x03, 0x12, 0x0f, 0x0a, 0x0b, 0x54,
-	0x45, 0x58, 0x54, 0x5f, 0x46, 0x4f, 0x52, 0x4d, 0x41, 0x54, 0x10, 0x04, 0x2a, 0x8f, 0x01, 0x0a,
-	0x0c, 0x54, 0x65, 0x73, 0x74, 0x43, 0x61, 0x74, 0x65, 0x67, 0x6f, 0x72, 0x79, 0x12, 0x14, 0x0a,
-	0x10, 0x55, 0x4e, 0x53, 0x50, 0x45, 0x43, 0x49, 0x46, 0x49, 0x45, 0x44, 0x5f, 0x54, 0x45, 0x53,
-	0x54, 0x10, 0x00, 0x12, 0x0f, 0x0a, 0x0b, 0x42, 0x49, 0x4e, 0x41, 0x52, 0x59, 0x5f, 0x54, 0x45,
-	0x53, 0x54, 0x10, 0x01, 0x12, 0x0d, 0x0a, 0x09, 0x4a, 0x53, 0x4f, 0x4e, 0x5f, 0x54, 0x45, 0x53,
-	0x54, 0x10, 0x02, 0x12, 0x24, 0x0a, 0x20, 0x4a, 0x53, 0x4f, 0x4e, 0x5f, 0x49, 0x47, 0x4e, 0x4f,
-	0x52, 0x45, 0x5f, 0x55, 0x4e, 0x4b, 0x4e, 0x4f, 0x57, 0x4e, 0x5f, 0x50, 0x41, 0x52, 0x53, 0x49,
-	0x4e, 0x47, 0x5f, 0x54, 0x45, 0x53, 0x54, 0x10, 0x03, 0x12, 0x0d, 0x0a, 0x09, 0x4a, 0x53, 0x50,
-	0x42, 0x5f, 0x54, 0x45, 0x53, 0x54, 0x10, 0x04, 0x12, 0x14, 0x0a, 0x10, 0x54, 0x45, 0x58, 0x54,
-	0x5f, 0x46, 0x4f, 0x52, 0x4d, 0x41, 0x54, 0x5f, 0x54, 0x45, 0x53, 0x54, 0x10, 0x05, 0x42, 0x5d,
-	0x0a, 0x1f, 0x63, 0x6f, 0x6d, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f,
-	0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x63, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x6e, 0x63,
-	0x65, 0x5a, 0x3a, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61, 0x6e, 0x67,
-	0x2e, 0x6f, 0x72, 0x67, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2f, 0x69, 0x6e,
-	0x74, 0x65, 0x72, 0x6e, 0x61, 0x6c, 0x2f, 0x74, 0x65, 0x73, 0x74, 0x70, 0x72, 0x6f, 0x74, 0x6f,
-	0x73, 0x2f, 0x63, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x6e, 0x63, 0x65, 0x62, 0x06, 0x70,
-	0x72, 0x6f, 0x74, 0x6f, 0x33,
+	0x12, 0x30, 0x0a, 0x14, 0x70, 0x72, 0x69, 0x6e, 0x74, 0x5f, 0x75, 0x6e, 0x6b, 0x6e, 0x6f, 0x77,
+	0x6e, 0x5f, 0x66, 0x69, 0x65, 0x6c, 0x64, 0x73, 0x18, 0x09, 0x20, 0x01, 0x28, 0x08, 0x52, 0x12,
+	0x70, 0x72, 0x69, 0x6e, 0x74, 0x55, 0x6e, 0x6b, 0x6e, 0x6f, 0x77, 0x6e, 0x46, 0x69, 0x65, 0x6c,
+	0x64, 0x73, 0x42, 0x09, 0x0a, 0x07, 0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x22, 0xcc, 0x02,
+	0x0a, 0x13, 0x43, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x6e, 0x63, 0x65, 0x52, 0x65, 0x73,
+	0x70, 0x6f, 0x6e, 0x73, 0x65, 0x12, 0x21, 0x0a, 0x0b, 0x70, 0x61, 0x72, 0x73, 0x65, 0x5f, 0x65,
+	0x72, 0x72, 0x6f, 0x72, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52, 0x0a, 0x70, 0x61,
+	0x72, 0x73, 0x65, 0x45, 0x72, 0x72, 0x6f, 0x72, 0x12, 0x29, 0x0a, 0x0f, 0x73, 0x65, 0x72, 0x69,
+	0x61, 0x6c, 0x69, 0x7a, 0x65, 0x5f, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x18, 0x06, 0x20, 0x01, 0x28,
+	0x09, 0x48, 0x00, 0x52, 0x0e, 0x73, 0x65, 0x72, 0x69, 0x61, 0x6c, 0x69, 0x7a, 0x65, 0x45, 0x72,
+	0x72, 0x6f, 0x72, 0x12, 0x25, 0x0a, 0x0d, 0x72, 0x75, 0x6e, 0x74, 0x69, 0x6d, 0x65, 0x5f, 0x65,
+	0x72, 0x72, 0x6f, 0x72, 0x18, 0x02, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52, 0x0c, 0x72, 0x75,
+	0x6e, 0x74, 0x69, 0x6d, 0x65, 0x45, 0x72, 0x72, 0x6f, 0x72, 0x12, 0x2b, 0x0a, 0x10, 0x70, 0x72,
+	0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x5f, 0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18, 0x03,
+	0x20, 0x01, 0x28, 0x0c, 0x48, 0x00, 0x52, 0x0f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66,
+	0x50, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x12, 0x23, 0x0a, 0x0c, 0x6a, 0x73, 0x6f, 0x6e, 0x5f,
+	0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18, 0x04, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52,
+	0x0b, 0x6a, 0x73, 0x6f, 0x6e, 0x50, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x12, 0x1a, 0x0a, 0x07,
+	0x73, 0x6b, 0x69, 0x70, 0x70, 0x65, 0x64, 0x18, 0x05, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00, 0x52,
+	0x07, 0x73, 0x6b, 0x69, 0x70, 0x70, 0x65, 0x64, 0x12, 0x23, 0x0a, 0x0c, 0x6a, 0x73, 0x70, 0x62,
+	0x5f, 0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18, 0x07, 0x20, 0x01, 0x28, 0x09, 0x48, 0x00,
+	0x52, 0x0b, 0x6a, 0x73, 0x70, 0x62, 0x50, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x12, 0x23, 0x0a,
+	0x0c, 0x74, 0x65, 0x78, 0x74, 0x5f, 0x70, 0x61, 0x79, 0x6c, 0x6f, 0x61, 0x64, 0x18, 0x08, 0x20,
+	0x01, 0x28, 0x09, 0x48, 0x00, 0x52, 0x0b, 0x74, 0x65, 0x78, 0x74, 0x50, 0x61, 0x79, 0x6c, 0x6f,
+	0x61, 0x64, 0x42, 0x08, 0x0a, 0x06, 0x72, 0x65, 0x73, 0x75, 0x6c, 0x74, 0x22, 0x4e, 0x0a, 0x12,
+	0x4a, 0x73, 0x70, 0x62, 0x45, 0x6e, 0x63, 0x6f, 0x64, 0x69, 0x6e, 0x67, 0x43, 0x6f, 0x6e, 0x66,
+	0x69, 0x67, 0x12, 0x38, 0x0a, 0x19, 0x75, 0x73, 0x65, 0x5f, 0x6a, 0x73, 0x70, 0x62, 0x5f, 0x61,
+	0x72, 0x72, 0x61, 0x79, 0x5f, 0x61, 0x6e, 0x79, 0x5f, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x18,
+	0x01, 0x20, 0x01, 0x28, 0x08, 0x52, 0x15, 0x75, 0x73, 0x65, 0x4a, 0x73, 0x70, 0x62, 0x41, 0x72,
+	0x72, 0x61, 0x79, 0x41, 0x6e, 0x79, 0x46, 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x2a, 0x50, 0x0a, 0x0a,
+	0x57, 0x69, 0x72, 0x65, 0x46, 0x6f, 0x72, 0x6d, 0x61, 0x74, 0x12, 0x0f, 0x0a, 0x0b, 0x55, 0x4e,
+	0x53, 0x50, 0x45, 0x43, 0x49, 0x46, 0x49, 0x45, 0x44, 0x10, 0x00, 0x12, 0x0c, 0x0a, 0x08, 0x50,
+	0x52, 0x4f, 0x54, 0x4f, 0x42, 0x55, 0x46, 0x10, 0x01, 0x12, 0x08, 0x0a, 0x04, 0x4a, 0x53, 0x4f,
+	0x4e, 0x10, 0x02, 0x12, 0x08, 0x0a, 0x04, 0x4a, 0x53, 0x50, 0x42, 0x10, 0x03, 0x12, 0x0f, 0x0a,
+	0x0b, 0x54, 0x45, 0x58, 0x54, 0x5f, 0x46, 0x4f, 0x52, 0x4d, 0x41, 0x54, 0x10, 0x04, 0x2a, 0x8f,
+	0x01, 0x0a, 0x0c, 0x54, 0x65, 0x73, 0x74, 0x43, 0x61, 0x74, 0x65, 0x67, 0x6f, 0x72, 0x79, 0x12,
+	0x14, 0x0a, 0x10, 0x55, 0x4e, 0x53, 0x50, 0x45, 0x43, 0x49, 0x46, 0x49, 0x45, 0x44, 0x5f, 0x54,
+	0x45, 0x53, 0x54, 0x10, 0x00, 0x12, 0x0f, 0x0a, 0x0b, 0x42, 0x49, 0x4e, 0x41, 0x52, 0x59, 0x5f,
+	0x54, 0x45, 0x53, 0x54, 0x10, 0x01, 0x12, 0x0d, 0x0a, 0x09, 0x4a, 0x53, 0x4f, 0x4e, 0x5f, 0x54,
+	0x45, 0x53, 0x54, 0x10, 0x02, 0x12, 0x24, 0x0a, 0x20, 0x4a, 0x53, 0x4f, 0x4e, 0x5f, 0x49, 0x47,
+	0x4e, 0x4f, 0x52, 0x45, 0x5f, 0x55, 0x4e, 0x4b, 0x4e, 0x4f, 0x57, 0x4e, 0x5f, 0x50, 0x41, 0x52,
+	0x53, 0x49, 0x4e, 0x47, 0x5f, 0x54, 0x45, 0x53, 0x54, 0x10, 0x03, 0x12, 0x0d, 0x0a, 0x09, 0x4a,
+	0x53, 0x50, 0x42, 0x5f, 0x54, 0x45, 0x53, 0x54, 0x10, 0x04, 0x12, 0x14, 0x0a, 0x10, 0x54, 0x45,
+	0x58, 0x54, 0x5f, 0x46, 0x4f, 0x52, 0x4d, 0x41, 0x54, 0x5f, 0x54, 0x45, 0x53, 0x54, 0x10, 0x05,
+	0x42, 0x5d, 0x0a, 0x1f, 0x63, 0x6f, 0x6d, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70,
+	0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x63, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61,
+	0x6e, 0x63, 0x65, 0x5a, 0x3a, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61,
+	0x6e, 0x67, 0x2e, 0x6f, 0x72, 0x67, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2f,
+	0x69, 0x6e, 0x74, 0x65, 0x72, 0x6e, 0x61, 0x6c, 0x2f, 0x74, 0x65, 0x73, 0x74, 0x70, 0x72, 0x6f,
+	0x74, 0x6f, 0x73, 0x2f, 0x63, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x6e, 0x63, 0x65, 0x62,
+	0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
diff --git a/internal/testprotos/conformance/test_messages_proto2.pb.go b/internal/testprotos/conformance/test_messages_proto2.pb.go
index d93595f..60b7614 100644
--- a/internal/testprotos/conformance/test_messages_proto2.pb.go
+++ b/internal/testprotos/conformance/test_messages_proto2.pb.go
@@ -33,6 +33,8 @@
 // - conformance tests
 //
 
+// LINT: ALLOW_GROUPS
+
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: google/protobuf/test_messages_proto2.proto
 
@@ -1052,6 +1054,88 @@
 	return 0
 }
 
+type UnknownToTestAllTypes struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	OptionalInt32  *int32                               `protobuf:"varint,1001,opt,name=optional_int32,json=optionalInt32" json:"optional_int32,omitempty"`
+	OptionalString *string                              `protobuf:"bytes,1002,opt,name=optional_string,json=optionalString" json:"optional_string,omitempty"`
+	NestedMessage  *ForeignMessageProto2                `protobuf:"bytes,1003,opt,name=nested_message,json=nestedMessage" json:"nested_message,omitempty"`
+	Optionalgroup  *UnknownToTestAllTypes_OptionalGroup `protobuf:"group,1004,opt,name=OptionalGroup,json=optionalgroup" json:"optionalgroup,omitempty"`
+	OptionalBool   *bool                                `protobuf:"varint,1006,opt,name=optional_bool,json=optionalBool" json:"optional_bool,omitempty"`
+	RepeatedInt32  []int32                              `protobuf:"varint,1011,rep,name=repeated_int32,json=repeatedInt32" json:"repeated_int32,omitempty"`
+}
+
+func (x *UnknownToTestAllTypes) Reset() {
+	*x = UnknownToTestAllTypes{}
+}
+
+func (x *UnknownToTestAllTypes) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*UnknownToTestAllTypes) ProtoMessage() {}
+
+func (x *UnknownToTestAllTypes) ProtoReflect() protoreflect.Message {
+	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[2]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use UnknownToTestAllTypes.ProtoReflect.Descriptor instead.
+func (*UnknownToTestAllTypes) Descriptor() ([]byte, []int) {
+	return file_google_protobuf_test_messages_proto2_proto_rawDescGZIP(), []int{2}
+}
+
+func (x *UnknownToTestAllTypes) GetOptionalInt32() int32 {
+	if x != nil && x.OptionalInt32 != nil {
+		return *x.OptionalInt32
+	}
+	return 0
+}
+
+func (x *UnknownToTestAllTypes) GetOptionalString() string {
+	if x != nil && x.OptionalString != nil {
+		return *x.OptionalString
+	}
+	return ""
+}
+
+func (x *UnknownToTestAllTypes) GetNestedMessage() *ForeignMessageProto2 {
+	if x != nil {
+		return x.NestedMessage
+	}
+	return nil
+}
+
+func (x *UnknownToTestAllTypes) GetOptionalgroup() *UnknownToTestAllTypes_OptionalGroup {
+	if x != nil {
+		return x.Optionalgroup
+	}
+	return nil
+}
+
+func (x *UnknownToTestAllTypes) GetOptionalBool() bool {
+	if x != nil && x.OptionalBool != nil {
+		return *x.OptionalBool
+	}
+	return false
+}
+
+func (x *UnknownToTestAllTypes) GetRepeatedInt32() []int32 {
+	if x != nil {
+		return x.RepeatedInt32
+	}
+	return nil
+}
+
 type TestAllTypesProto2_NestedMessage struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
@@ -1072,7 +1156,7 @@
 func (*TestAllTypesProto2_NestedMessage) ProtoMessage() {}
 
 func (x *TestAllTypesProto2_NestedMessage) ProtoReflect() protoreflect.Message {
-	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[2]
+	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[3]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -1123,7 +1207,7 @@
 func (*TestAllTypesProto2_Data) ProtoMessage() {}
 
 func (x *TestAllTypesProto2_Data) ProtoReflect() protoreflect.Message {
-	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[22]
+	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[23]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -1172,7 +1256,7 @@
 func (*TestAllTypesProto2_MessageSetCorrect) ProtoMessage() {}
 
 func (x *TestAllTypesProto2_MessageSetCorrect) ProtoReflect() protoreflect.Message {
-	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[23]
+	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[24]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -1216,7 +1300,7 @@
 func (*TestAllTypesProto2_MessageSetCorrectExtension1) ProtoMessage() {}
 
 func (x *TestAllTypesProto2_MessageSetCorrectExtension1) ProtoReflect() protoreflect.Message {
-	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[24]
+	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[25]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -1258,7 +1342,7 @@
 func (*TestAllTypesProto2_MessageSetCorrectExtension2) ProtoMessage() {}
 
 func (x *TestAllTypesProto2_MessageSetCorrectExtension2) ProtoReflect() protoreflect.Message {
-	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[25]
+	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[26]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -1281,6 +1365,48 @@
 	return 0
 }
 
+type UnknownToTestAllTypes_OptionalGroup struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	A *int32 `protobuf:"varint,1,opt,name=a" json:"a,omitempty"`
+}
+
+func (x *UnknownToTestAllTypes_OptionalGroup) Reset() {
+	*x = UnknownToTestAllTypes_OptionalGroup{}
+}
+
+func (x *UnknownToTestAllTypes_OptionalGroup) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*UnknownToTestAllTypes_OptionalGroup) ProtoMessage() {}
+
+func (x *UnknownToTestAllTypes_OptionalGroup) ProtoReflect() protoreflect.Message {
+	mi := &file_google_protobuf_test_messages_proto2_proto_msgTypes[27]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use UnknownToTestAllTypes_OptionalGroup.ProtoReflect.Descriptor instead.
+func (*UnknownToTestAllTypes_OptionalGroup) Descriptor() ([]byte, []int) {
+	return file_google_protobuf_test_messages_proto2_proto_rawDescGZIP(), []int{2, 0}
+}
+
+func (x *UnknownToTestAllTypes_OptionalGroup) GetA() int32 {
+	if x != nil && x.A != nil {
+		return *x.A
+	}
+	return 0
+}
+
 var file_google_protobuf_test_messages_proto2_proto_extDescs = []protoiface.ExtensionDescV1{
 	{
 		ExtendedType:  (*TestAllTypesProto2)(nil),
@@ -1329,7 +1455,7 @@
 	0x66, 0x2f, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x73, 0x5f,
 	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x1d, 0x70, 0x72,
 	0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x5f, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x6d, 0x65, 0x73, 0x73,
-	0x61, 0x67, 0x65, 0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x22, 0xc4, 0x40, 0x0a, 0x12,
+	0x61, 0x67, 0x65, 0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x22, 0xcc, 0x40, 0x0a, 0x12,
 	0x54, 0x65, 0x73, 0x74, 0x41, 0x6c, 0x6c, 0x54, 0x79, 0x70, 0x65, 0x73, 0x50, 0x72, 0x6f, 0x74,
 	0x6f, 0x32, 0x12, 0x25, 0x0a, 0x0e, 0x6f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x5f, 0x69,
 	0x6e, 0x74, 0x33, 0x32, 0x18, 0x01, 0x20, 0x01, 0x28, 0x05, 0x52, 0x0d, 0x6f, 0x70, 0x74, 0x69,
@@ -1846,26 +1972,53 @@
 	0x01, 0x12, 0x07, 0x0a, 0x03, 0x42, 0x41, 0x5a, 0x10, 0x02, 0x12, 0x10, 0x0a, 0x03, 0x4e, 0x45,
 	0x47, 0x10, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x01, 0x2a, 0x05, 0x08, 0x78,
 	0x10, 0xc9, 0x01, 0x42, 0x0d, 0x0a, 0x0b, 0x6f, 0x6e, 0x65, 0x6f, 0x66, 0x5f, 0x66, 0x69, 0x65,
-	0x6c, 0x64, 0x22, 0x24, 0x0a, 0x14, 0x46, 0x6f, 0x72, 0x65, 0x69, 0x67, 0x6e, 0x4d, 0x65, 0x73,
-	0x73, 0x61, 0x67, 0x65, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x12, 0x0c, 0x0a, 0x01, 0x63, 0x18,
-	0x01, 0x20, 0x01, 0x28, 0x05, 0x52, 0x01, 0x63, 0x2a, 0x46, 0x0a, 0x11, 0x46, 0x6f, 0x72, 0x65,
-	0x69, 0x67, 0x6e, 0x45, 0x6e, 0x75, 0x6d, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x12, 0x0f, 0x0a,
-	0x0b, 0x46, 0x4f, 0x52, 0x45, 0x49, 0x47, 0x4e, 0x5f, 0x46, 0x4f, 0x4f, 0x10, 0x00, 0x12, 0x0f,
-	0x0a, 0x0b, 0x46, 0x4f, 0x52, 0x45, 0x49, 0x47, 0x4e, 0x5f, 0x42, 0x41, 0x52, 0x10, 0x01, 0x12,
-	0x0f, 0x0a, 0x0b, 0x46, 0x4f, 0x52, 0x45, 0x49, 0x47, 0x4e, 0x5f, 0x42, 0x41, 0x5a, 0x10, 0x02,
-	0x3a, 0x5a, 0x0a, 0x0f, 0x65, 0x78, 0x74, 0x65, 0x6e, 0x73, 0x69, 0x6f, 0x6e, 0x5f, 0x69, 0x6e,
-	0x74, 0x33, 0x32, 0x12, 0x31, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x5f, 0x74,
-	0x65, 0x73, 0x74, 0x5f, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x73, 0x2e, 0x70, 0x72, 0x6f,
-	0x74, 0x6f, 0x32, 0x2e, 0x54, 0x65, 0x73, 0x74, 0x41, 0x6c, 0x6c, 0x54, 0x79, 0x70, 0x65, 0x73,
-	0x50, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x18, 0x78, 0x20, 0x01, 0x28, 0x05, 0x52, 0x0e, 0x65, 0x78,
-	0x74, 0x65, 0x6e, 0x73, 0x69, 0x6f, 0x6e, 0x49, 0x6e, 0x74, 0x33, 0x32, 0x42, 0x6b, 0x0a, 0x28,
-	0x63, 0x6f, 0x6d, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f,
-	0x62, 0x75, 0x66, 0x5f, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65,
-	0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x48, 0x01, 0x5a, 0x3a, 0x67, 0x6f, 0x6f, 0x67,
-	0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61, 0x6e, 0x67, 0x2e, 0x6f, 0x72, 0x67, 0x2f, 0x70, 0x72,
-	0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2f, 0x69, 0x6e, 0x74, 0x65, 0x72, 0x6e, 0x61, 0x6c, 0x2f,
-	0x74, 0x65, 0x73, 0x74, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x73, 0x2f, 0x63, 0x6f, 0x6e, 0x66, 0x6f,
-	0x72, 0x6d, 0x61, 0x6e, 0x63, 0x65, 0xf8, 0x01, 0x01,
+	0x6c, 0x64, 0x4a, 0x06, 0x08, 0xe8, 0x07, 0x10, 0x90, 0x4e, 0x22, 0x24, 0x0a, 0x14, 0x46, 0x6f,
+	0x72, 0x65, 0x69, 0x67, 0x6e, 0x4d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x50, 0x72, 0x6f, 0x74,
+	0x6f, 0x32, 0x12, 0x0c, 0x0a, 0x01, 0x63, 0x18, 0x01, 0x20, 0x01, 0x28, 0x05, 0x52, 0x01, 0x63,
+	0x22, 0x9e, 0x03, 0x0a, 0x15, 0x55, 0x6e, 0x6b, 0x6e, 0x6f, 0x77, 0x6e, 0x54, 0x6f, 0x54, 0x65,
+	0x73, 0x74, 0x41, 0x6c, 0x6c, 0x54, 0x79, 0x70, 0x65, 0x73, 0x12, 0x26, 0x0a, 0x0e, 0x6f, 0x70,
+	0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x5f, 0x69, 0x6e, 0x74, 0x33, 0x32, 0x18, 0xe9, 0x07, 0x20,
+	0x01, 0x28, 0x05, 0x52, 0x0d, 0x6f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x49, 0x6e, 0x74,
+	0x33, 0x32, 0x12, 0x28, 0x0a, 0x0f, 0x6f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x5f, 0x73,
+	0x74, 0x72, 0x69, 0x6e, 0x67, 0x18, 0xea, 0x07, 0x20, 0x01, 0x28, 0x09, 0x52, 0x0e, 0x6f, 0x70,
+	0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x53, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x12, 0x5b, 0x0a, 0x0e,
+	0x6e, 0x65, 0x73, 0x74, 0x65, 0x64, 0x5f, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x18, 0xeb,
+	0x07, 0x20, 0x01, 0x28, 0x0b, 0x32, 0x33, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66,
+	0x5f, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x73, 0x2e, 0x70,
+	0x72, 0x6f, 0x74, 0x6f, 0x32, 0x2e, 0x46, 0x6f, 0x72, 0x65, 0x69, 0x67, 0x6e, 0x4d, 0x65, 0x73,
+	0x73, 0x61, 0x67, 0x65, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x52, 0x0d, 0x6e, 0x65, 0x73, 0x74,
+	0x65, 0x64, 0x4d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x12, 0x69, 0x0a, 0x0d, 0x6f, 0x70, 0x74,
+	0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x67, 0x72, 0x6f, 0x75, 0x70, 0x18, 0xec, 0x07, 0x20, 0x01, 0x28,
+	0x0a, 0x32, 0x42, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x5f, 0x74, 0x65, 0x73,
+	0x74, 0x5f, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f,
+	0x32, 0x2e, 0x55, 0x6e, 0x6b, 0x6e, 0x6f, 0x77, 0x6e, 0x54, 0x6f, 0x54, 0x65, 0x73, 0x74, 0x41,
+	0x6c, 0x6c, 0x54, 0x79, 0x70, 0x65, 0x73, 0x2e, 0x4f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c,
+	0x47, 0x72, 0x6f, 0x75, 0x70, 0x52, 0x0d, 0x6f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x67,
+	0x72, 0x6f, 0x75, 0x70, 0x12, 0x24, 0x0a, 0x0d, 0x6f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c,
+	0x5f, 0x62, 0x6f, 0x6f, 0x6c, 0x18, 0xee, 0x07, 0x20, 0x01, 0x28, 0x08, 0x52, 0x0c, 0x6f, 0x70,
+	0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x42, 0x6f, 0x6f, 0x6c, 0x12, 0x26, 0x0a, 0x0e, 0x72, 0x65,
+	0x70, 0x65, 0x61, 0x74, 0x65, 0x64, 0x5f, 0x69, 0x6e, 0x74, 0x33, 0x32, 0x18, 0xf3, 0x07, 0x20,
+	0x03, 0x28, 0x05, 0x52, 0x0d, 0x72, 0x65, 0x70, 0x65, 0x61, 0x74, 0x65, 0x64, 0x49, 0x6e, 0x74,
+	0x33, 0x32, 0x1a, 0x1d, 0x0a, 0x0d, 0x4f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x61, 0x6c, 0x47, 0x72,
+	0x6f, 0x75, 0x70, 0x12, 0x0c, 0x0a, 0x01, 0x61, 0x18, 0x01, 0x20, 0x01, 0x28, 0x05, 0x52, 0x01,
+	0x61, 0x2a, 0x46, 0x0a, 0x11, 0x46, 0x6f, 0x72, 0x65, 0x69, 0x67, 0x6e, 0x45, 0x6e, 0x75, 0x6d,
+	0x50, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x12, 0x0f, 0x0a, 0x0b, 0x46, 0x4f, 0x52, 0x45, 0x49, 0x47,
+	0x4e, 0x5f, 0x46, 0x4f, 0x4f, 0x10, 0x00, 0x12, 0x0f, 0x0a, 0x0b, 0x46, 0x4f, 0x52, 0x45, 0x49,
+	0x47, 0x4e, 0x5f, 0x42, 0x41, 0x52, 0x10, 0x01, 0x12, 0x0f, 0x0a, 0x0b, 0x46, 0x4f, 0x52, 0x45,
+	0x49, 0x47, 0x4e, 0x5f, 0x42, 0x41, 0x5a, 0x10, 0x02, 0x3a, 0x5a, 0x0a, 0x0f, 0x65, 0x78, 0x74,
+	0x65, 0x6e, 0x73, 0x69, 0x6f, 0x6e, 0x5f, 0x69, 0x6e, 0x74, 0x33, 0x32, 0x12, 0x31, 0x2e, 0x70,
+	0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x5f, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x6d, 0x65, 0x73,
+	0x73, 0x61, 0x67, 0x65, 0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x2e, 0x54, 0x65, 0x73,
+	0x74, 0x41, 0x6c, 0x6c, 0x54, 0x79, 0x70, 0x65, 0x73, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x18,
+	0x78, 0x20, 0x01, 0x28, 0x05, 0x52, 0x0e, 0x65, 0x78, 0x74, 0x65, 0x6e, 0x73, 0x69, 0x6f, 0x6e,
+	0x49, 0x6e, 0x74, 0x33, 0x32, 0x42, 0x6b, 0x0a, 0x28, 0x63, 0x6f, 0x6d, 0x2e, 0x67, 0x6f, 0x6f,
+	0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x5f, 0x74, 0x65, 0x73,
+	0x74, 0x5f, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f,
+	0x32, 0x48, 0x01, 0x5a, 0x3a, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x67, 0x6f, 0x6c, 0x61,
+	0x6e, 0x67, 0x2e, 0x6f, 0x72, 0x67, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2f,
+	0x69, 0x6e, 0x74, 0x65, 0x72, 0x6e, 0x61, 0x6c, 0x2f, 0x74, 0x65, 0x73, 0x74, 0x70, 0x72, 0x6f,
+	0x74, 0x6f, 0x73, 0x2f, 0x63, 0x6f, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61, 0x6e, 0x63, 0x65, 0xf8,
+	0x01, 0x01,
 }
 
 var (
@@ -1881,84 +2034,88 @@
 }
 
 var file_google_protobuf_test_messages_proto2_proto_enumTypes = make([]protoimpl.EnumInfo, 2)
-var file_google_protobuf_test_messages_proto2_proto_msgTypes = make([]protoimpl.MessageInfo, 26)
+var file_google_protobuf_test_messages_proto2_proto_msgTypes = make([]protoimpl.MessageInfo, 28)
 var file_google_protobuf_test_messages_proto2_proto_goTypes = []interface{}{
 	(ForeignEnumProto2)(0),                   // 0: protobuf_test_messages.proto2.ForeignEnumProto2
 	(TestAllTypesProto2_NestedEnum)(0),       // 1: protobuf_test_messages.proto2.TestAllTypesProto2.NestedEnum
 	(*TestAllTypesProto2)(nil),               // 2: protobuf_test_messages.proto2.TestAllTypesProto2
 	(*ForeignMessageProto2)(nil),             // 3: protobuf_test_messages.proto2.ForeignMessageProto2
-	(*TestAllTypesProto2_NestedMessage)(nil), // 4: protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
-	nil,                                      // 5: protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32Int32Entry
-	nil,                                      // 6: protobuf_test_messages.proto2.TestAllTypesProto2.MapInt64Int64Entry
-	nil,                                      // 7: protobuf_test_messages.proto2.TestAllTypesProto2.MapUint32Uint32Entry
-	nil,                                      // 8: protobuf_test_messages.proto2.TestAllTypesProto2.MapUint64Uint64Entry
-	nil,                                      // 9: protobuf_test_messages.proto2.TestAllTypesProto2.MapSint32Sint32Entry
-	nil,                                      // 10: protobuf_test_messages.proto2.TestAllTypesProto2.MapSint64Sint64Entry
-	nil,                                      // 11: protobuf_test_messages.proto2.TestAllTypesProto2.MapFixed32Fixed32Entry
-	nil,                                      // 12: protobuf_test_messages.proto2.TestAllTypesProto2.MapFixed64Fixed64Entry
-	nil,                                      // 13: protobuf_test_messages.proto2.TestAllTypesProto2.MapSfixed32Sfixed32Entry
-	nil,                                      // 14: protobuf_test_messages.proto2.TestAllTypesProto2.MapSfixed64Sfixed64Entry
-	nil,                                      // 15: protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32FloatEntry
-	nil,                                      // 16: protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32DoubleEntry
-	nil,                                      // 17: protobuf_test_messages.proto2.TestAllTypesProto2.MapBoolBoolEntry
-	nil,                                      // 18: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringStringEntry
-	nil,                                      // 19: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringBytesEntry
-	nil,                                      // 20: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedMessageEntry
-	nil,                                      // 21: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignMessageEntry
-	nil,                                      // 22: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedEnumEntry
-	nil,                                      // 23: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignEnumEntry
-	(*TestAllTypesProto2_Data)(nil),          // 24: protobuf_test_messages.proto2.TestAllTypesProto2.Data
-	(*TestAllTypesProto2_MessageSetCorrect)(nil),           // 25: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrect
-	(*TestAllTypesProto2_MessageSetCorrectExtension1)(nil), // 26: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension1
-	(*TestAllTypesProto2_MessageSetCorrectExtension2)(nil), // 27: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension2
+	(*UnknownToTestAllTypes)(nil),            // 4: protobuf_test_messages.proto2.UnknownToTestAllTypes
+	(*TestAllTypesProto2_NestedMessage)(nil), // 5: protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
+	nil,                                      // 6: protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32Int32Entry
+	nil,                                      // 7: protobuf_test_messages.proto2.TestAllTypesProto2.MapInt64Int64Entry
+	nil,                                      // 8: protobuf_test_messages.proto2.TestAllTypesProto2.MapUint32Uint32Entry
+	nil,                                      // 9: protobuf_test_messages.proto2.TestAllTypesProto2.MapUint64Uint64Entry
+	nil,                                      // 10: protobuf_test_messages.proto2.TestAllTypesProto2.MapSint32Sint32Entry
+	nil,                                      // 11: protobuf_test_messages.proto2.TestAllTypesProto2.MapSint64Sint64Entry
+	nil,                                      // 12: protobuf_test_messages.proto2.TestAllTypesProto2.MapFixed32Fixed32Entry
+	nil,                                      // 13: protobuf_test_messages.proto2.TestAllTypesProto2.MapFixed64Fixed64Entry
+	nil,                                      // 14: protobuf_test_messages.proto2.TestAllTypesProto2.MapSfixed32Sfixed32Entry
+	nil,                                      // 15: protobuf_test_messages.proto2.TestAllTypesProto2.MapSfixed64Sfixed64Entry
+	nil,                                      // 16: protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32FloatEntry
+	nil,                                      // 17: protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32DoubleEntry
+	nil,                                      // 18: protobuf_test_messages.proto2.TestAllTypesProto2.MapBoolBoolEntry
+	nil,                                      // 19: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringStringEntry
+	nil,                                      // 20: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringBytesEntry
+	nil,                                      // 21: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedMessageEntry
+	nil,                                      // 22: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignMessageEntry
+	nil,                                      // 23: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedEnumEntry
+	nil,                                      // 24: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignEnumEntry
+	(*TestAllTypesProto2_Data)(nil),          // 25: protobuf_test_messages.proto2.TestAllTypesProto2.Data
+	(*TestAllTypesProto2_MessageSetCorrect)(nil),           // 26: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrect
+	(*TestAllTypesProto2_MessageSetCorrectExtension1)(nil), // 27: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension1
+	(*TestAllTypesProto2_MessageSetCorrectExtension2)(nil), // 28: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension2
+	(*UnknownToTestAllTypes_OptionalGroup)(nil),            // 29: protobuf_test_messages.proto2.UnknownToTestAllTypes.OptionalGroup
 }
 var file_google_protobuf_test_messages_proto2_proto_depIdxs = []int32{
-	4,  // 0: protobuf_test_messages.proto2.TestAllTypesProto2.optional_nested_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
+	5,  // 0: protobuf_test_messages.proto2.TestAllTypesProto2.optional_nested_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
 	3,  // 1: protobuf_test_messages.proto2.TestAllTypesProto2.optional_foreign_message:type_name -> protobuf_test_messages.proto2.ForeignMessageProto2
 	1,  // 2: protobuf_test_messages.proto2.TestAllTypesProto2.optional_nested_enum:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedEnum
 	0,  // 3: protobuf_test_messages.proto2.TestAllTypesProto2.optional_foreign_enum:type_name -> protobuf_test_messages.proto2.ForeignEnumProto2
 	2,  // 4: protobuf_test_messages.proto2.TestAllTypesProto2.recursive_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2
-	4,  // 5: protobuf_test_messages.proto2.TestAllTypesProto2.repeated_nested_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
+	5,  // 5: protobuf_test_messages.proto2.TestAllTypesProto2.repeated_nested_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
 	3,  // 6: protobuf_test_messages.proto2.TestAllTypesProto2.repeated_foreign_message:type_name -> protobuf_test_messages.proto2.ForeignMessageProto2
 	1,  // 7: protobuf_test_messages.proto2.TestAllTypesProto2.repeated_nested_enum:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedEnum
 	0,  // 8: protobuf_test_messages.proto2.TestAllTypesProto2.repeated_foreign_enum:type_name -> protobuf_test_messages.proto2.ForeignEnumProto2
-	5,  // 9: protobuf_test_messages.proto2.TestAllTypesProto2.map_int32_int32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32Int32Entry
-	6,  // 10: protobuf_test_messages.proto2.TestAllTypesProto2.map_int64_int64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapInt64Int64Entry
-	7,  // 11: protobuf_test_messages.proto2.TestAllTypesProto2.map_uint32_uint32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapUint32Uint32Entry
-	8,  // 12: protobuf_test_messages.proto2.TestAllTypesProto2.map_uint64_uint64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapUint64Uint64Entry
-	9,  // 13: protobuf_test_messages.proto2.TestAllTypesProto2.map_sint32_sint32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapSint32Sint32Entry
-	10, // 14: protobuf_test_messages.proto2.TestAllTypesProto2.map_sint64_sint64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapSint64Sint64Entry
-	11, // 15: protobuf_test_messages.proto2.TestAllTypesProto2.map_fixed32_fixed32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapFixed32Fixed32Entry
-	12, // 16: protobuf_test_messages.proto2.TestAllTypesProto2.map_fixed64_fixed64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapFixed64Fixed64Entry
-	13, // 17: protobuf_test_messages.proto2.TestAllTypesProto2.map_sfixed32_sfixed32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapSfixed32Sfixed32Entry
-	14, // 18: protobuf_test_messages.proto2.TestAllTypesProto2.map_sfixed64_sfixed64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapSfixed64Sfixed64Entry
-	15, // 19: protobuf_test_messages.proto2.TestAllTypesProto2.map_int32_float:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32FloatEntry
-	16, // 20: protobuf_test_messages.proto2.TestAllTypesProto2.map_int32_double:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32DoubleEntry
-	17, // 21: protobuf_test_messages.proto2.TestAllTypesProto2.map_bool_bool:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapBoolBoolEntry
-	18, // 22: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_string:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringStringEntry
-	19, // 23: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_bytes:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringBytesEntry
-	20, // 24: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_nested_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedMessageEntry
-	21, // 25: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_foreign_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignMessageEntry
-	22, // 26: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_nested_enum:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedEnumEntry
-	23, // 27: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_foreign_enum:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignEnumEntry
-	4,  // 28: protobuf_test_messages.proto2.TestAllTypesProto2.oneof_nested_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
+	6,  // 9: protobuf_test_messages.proto2.TestAllTypesProto2.map_int32_int32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32Int32Entry
+	7,  // 10: protobuf_test_messages.proto2.TestAllTypesProto2.map_int64_int64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapInt64Int64Entry
+	8,  // 11: protobuf_test_messages.proto2.TestAllTypesProto2.map_uint32_uint32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapUint32Uint32Entry
+	9,  // 12: protobuf_test_messages.proto2.TestAllTypesProto2.map_uint64_uint64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapUint64Uint64Entry
+	10, // 13: protobuf_test_messages.proto2.TestAllTypesProto2.map_sint32_sint32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapSint32Sint32Entry
+	11, // 14: protobuf_test_messages.proto2.TestAllTypesProto2.map_sint64_sint64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapSint64Sint64Entry
+	12, // 15: protobuf_test_messages.proto2.TestAllTypesProto2.map_fixed32_fixed32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapFixed32Fixed32Entry
+	13, // 16: protobuf_test_messages.proto2.TestAllTypesProto2.map_fixed64_fixed64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapFixed64Fixed64Entry
+	14, // 17: protobuf_test_messages.proto2.TestAllTypesProto2.map_sfixed32_sfixed32:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapSfixed32Sfixed32Entry
+	15, // 18: protobuf_test_messages.proto2.TestAllTypesProto2.map_sfixed64_sfixed64:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapSfixed64Sfixed64Entry
+	16, // 19: protobuf_test_messages.proto2.TestAllTypesProto2.map_int32_float:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32FloatEntry
+	17, // 20: protobuf_test_messages.proto2.TestAllTypesProto2.map_int32_double:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapInt32DoubleEntry
+	18, // 21: protobuf_test_messages.proto2.TestAllTypesProto2.map_bool_bool:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapBoolBoolEntry
+	19, // 22: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_string:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringStringEntry
+	20, // 23: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_bytes:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringBytesEntry
+	21, // 24: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_nested_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedMessageEntry
+	22, // 25: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_foreign_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignMessageEntry
+	23, // 26: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_nested_enum:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedEnumEntry
+	24, // 27: protobuf_test_messages.proto2.TestAllTypesProto2.map_string_foreign_enum:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignEnumEntry
+	5,  // 28: protobuf_test_messages.proto2.TestAllTypesProto2.oneof_nested_message:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
 	1,  // 29: protobuf_test_messages.proto2.TestAllTypesProto2.oneof_enum:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedEnum
-	24, // 30: protobuf_test_messages.proto2.TestAllTypesProto2.data:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.Data
-	2,  // 31: protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage.corecursive:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2
-	4,  // 32: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedMessageEntry.value:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
-	3,  // 33: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignMessageEntry.value:type_name -> protobuf_test_messages.proto2.ForeignMessageProto2
-	1,  // 34: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedEnumEntry.value:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedEnum
-	0,  // 35: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignEnumEntry.value:type_name -> protobuf_test_messages.proto2.ForeignEnumProto2
-	2,  // 36: protobuf_test_messages.proto2.extension_int32:extendee -> protobuf_test_messages.proto2.TestAllTypesProto2
-	25, // 37: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension1.message_set_extension:extendee -> protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrect
-	25, // 38: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension2.message_set_extension:extendee -> protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrect
-	26, // 39: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension1.message_set_extension:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension1
-	27, // 40: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension2.message_set_extension:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension2
-	41, // [41:41] is the sub-list for method output_type
-	41, // [41:41] is the sub-list for method input_type
-	39, // [39:41] is the sub-list for extension type_name
-	36, // [36:39] is the sub-list for extension extendee
-	0,  // [0:36] is the sub-list for field type_name
+	25, // 30: protobuf_test_messages.proto2.TestAllTypesProto2.data:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.Data
+	3,  // 31: protobuf_test_messages.proto2.UnknownToTestAllTypes.nested_message:type_name -> protobuf_test_messages.proto2.ForeignMessageProto2
+	29, // 32: protobuf_test_messages.proto2.UnknownToTestAllTypes.optionalgroup:type_name -> protobuf_test_messages.proto2.UnknownToTestAllTypes.OptionalGroup
+	2,  // 33: protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage.corecursive:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2
+	5,  // 34: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedMessageEntry.value:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedMessage
+	3,  // 35: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignMessageEntry.value:type_name -> protobuf_test_messages.proto2.ForeignMessageProto2
+	1,  // 36: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringNestedEnumEntry.value:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.NestedEnum
+	0,  // 37: protobuf_test_messages.proto2.TestAllTypesProto2.MapStringForeignEnumEntry.value:type_name -> protobuf_test_messages.proto2.ForeignEnumProto2
+	2,  // 38: protobuf_test_messages.proto2.extension_int32:extendee -> protobuf_test_messages.proto2.TestAllTypesProto2
+	26, // 39: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension1.message_set_extension:extendee -> protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrect
+	26, // 40: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension2.message_set_extension:extendee -> protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrect
+	27, // 41: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension1.message_set_extension:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension1
+	28, // 42: protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension2.message_set_extension:type_name -> protobuf_test_messages.proto2.TestAllTypesProto2.MessageSetCorrectExtension2
+	43, // [43:43] is the sub-list for method output_type
+	43, // [43:43] is the sub-list for method input_type
+	41, // [41:43] is the sub-list for extension type_name
+	38, // [38:41] is the sub-list for extension extendee
+	0,  // [0:38] is the sub-list for field type_name
 }
 
 func init() { file_google_protobuf_test_messages_proto2_proto_init() }
@@ -1994,6 +2151,18 @@
 			}
 		}
 		file_google_protobuf_test_messages_proto2_proto_msgTypes[2].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*UnknownToTestAllTypes); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_google_protobuf_test_messages_proto2_proto_msgTypes[3].Exporter = func(v interface{}, i int) interface{} {
 			switch v := v.(*TestAllTypesProto2_NestedMessage); i {
 			case 0:
 				return &v.state
@@ -2005,7 +2174,7 @@
 				return nil
 			}
 		}
-		file_google_protobuf_test_messages_proto2_proto_msgTypes[22].Exporter = func(v interface{}, i int) interface{} {
+		file_google_protobuf_test_messages_proto2_proto_msgTypes[23].Exporter = func(v interface{}, i int) interface{} {
 			switch v := v.(*TestAllTypesProto2_Data); i {
 			case 0:
 				return &v.state
@@ -2017,7 +2186,7 @@
 				return nil
 			}
 		}
-		file_google_protobuf_test_messages_proto2_proto_msgTypes[23].Exporter = func(v interface{}, i int) interface{} {
+		file_google_protobuf_test_messages_proto2_proto_msgTypes[24].Exporter = func(v interface{}, i int) interface{} {
 			switch v := v.(*TestAllTypesProto2_MessageSetCorrect); i {
 			case 0:
 				return &v.state
@@ -2031,7 +2200,7 @@
 				return nil
 			}
 		}
-		file_google_protobuf_test_messages_proto2_proto_msgTypes[24].Exporter = func(v interface{}, i int) interface{} {
+		file_google_protobuf_test_messages_proto2_proto_msgTypes[25].Exporter = func(v interface{}, i int) interface{} {
 			switch v := v.(*TestAllTypesProto2_MessageSetCorrectExtension1); i {
 			case 0:
 				return &v.state
@@ -2043,7 +2212,7 @@
 				return nil
 			}
 		}
-		file_google_protobuf_test_messages_proto2_proto_msgTypes[25].Exporter = func(v interface{}, i int) interface{} {
+		file_google_protobuf_test_messages_proto2_proto_msgTypes[26].Exporter = func(v interface{}, i int) interface{} {
 			switch v := v.(*TestAllTypesProto2_MessageSetCorrectExtension2); i {
 			case 0:
 				return &v.state
@@ -2055,6 +2224,18 @@
 				return nil
 			}
 		}
+		file_google_protobuf_test_messages_proto2_proto_msgTypes[27].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*UnknownToTestAllTypes_OptionalGroup); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
 	}
 	file_google_protobuf_test_messages_proto2_proto_msgTypes[0].OneofWrappers = []interface{}{
 		(*TestAllTypesProto2_OneofUint32)(nil),
@@ -2073,7 +2254,7 @@
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_google_protobuf_test_messages_proto2_proto_rawDesc,
 			NumEnums:      2,
-			NumMessages:   26,
+			NumMessages:   28,
 			NumExtensions: 3,
 			NumServices:   0,
 		},
diff --git a/types/descriptorpb/descriptor.pb.go b/types/descriptorpb/descriptor.pb.go
index 30d77cc..ed41f31 100644
--- a/types/descriptorpb/descriptor.pb.go
+++ b/types/descriptorpb/descriptor.pb.go
@@ -1384,8 +1384,8 @@
 	// determining the namespace.
 	PhpNamespace *string `protobuf:"bytes,41,opt,name=php_namespace,json=phpNamespace" json:"php_namespace,omitempty"`
 	// Use this option to change the namespace of php generated metadata classes.
-	// Default is empty. When this option is empty, the proto file name will be used
-	// for determining the namespace.
+	// Default is empty. When this option is empty, the proto file name will be
+	// used for determining the namespace.
 	PhpMetadataNamespace *string `protobuf:"bytes,44,opt,name=php_metadata_namespace,json=phpMetadataNamespace" json:"php_metadata_namespace,omitempty"`
 	// Use this option to change the package of ruby generated classes. Default
 	// is empty. When this option is not set, the package name will be used for
@@ -1642,7 +1642,7 @@
 	//
 	// Implementations may choose not to generate the map_entry=true message, but
 	// use a native map in the target language to hold the keys and values.
-	// The reflection APIs in such implementions still need to work as
+	// The reflection APIs in such implementations still need to work as
 	// if the field is a repeated message field.
 	//
 	// NOTE: Do not set the option in .proto files. Always use the maps syntax
@@ -2388,7 +2388,7 @@
 	//   beginning of the "extend" block and is shared by all extensions within
 	//   the block.
 	// - Just because a location's span is a subset of some other location's span
-	//   does not mean that it is a descendent.  For example, a "group" defines
+	//   does not mean that it is a descendant.  For example, a "group" defines
 	//   both a type and a field in a single declaration.  Thus, the locations
 	//   corresponding to the type and field and their components will overlap.
 	// - Code which tries to interpret locations should probably be designed to
@@ -2483,8 +2483,8 @@
 	sizeCache     protoimpl.SizeCache
 	unknownFields protoimpl.UnknownFields
 
-	Start   *int32                 `protobuf:"varint,1,opt,name=start" json:"start,omitempty"`
-	End     *int32                 `protobuf:"varint,2,opt,name=end" json:"end,omitempty"`
+	Start   *int32                 `protobuf:"varint,1,opt,name=start" json:"start,omitempty"` // Inclusive.
+	End     *int32                 `protobuf:"varint,2,opt,name=end" json:"end,omitempty"`     // Exclusive.
 	Options *ExtensionRangeOptions `protobuf:"bytes,3,opt,name=options" json:"options,omitempty"`
 }
 
diff --git a/types/known/timestamppb/timestamp.pb.go b/types/known/timestamppb/timestamp.pb.go
index 27fa027..c1a50aa 100644
--- a/types/known/timestamppb/timestamp.pb.go
+++ b/types/known/timestamppb/timestamp.pb.go
@@ -113,11 +113,13 @@
 // 01:30 UTC on January 15, 2017.
 //
 // In JavaScript, one can convert a Date object to this format using the
-// standard [toISOString()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString)
+// standard
+// [toISOString()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString)
 // method. In Python, a standard `datetime.datetime` object can be converted
-// to this format using [`strftime`](https://docs.python.org/2/library/time.html#time.strftime)
-// with the time format spec '%Y-%m-%dT%H:%M:%S.%fZ'. Likewise, in Java, one
-// can use the Joda Time's [`ISODateTimeFormat.dateTime()`](
+// to this format using
+// [`strftime`](https://docs.python.org/2/library/time.html#time.strftime) with
+// the time format spec '%Y-%m-%dT%H:%M:%S.%fZ'. Likewise, in Java, one can use
+// the Joda Time's [`ISODateTimeFormat.dateTime()`](
 // http://www.joda.org/joda-time/apidocs/org/joda/time/format/ISODateTimeFormat.html#dateTime%2D%2D
 // ) to obtain a formatter capable of generating timestamps in this format.
 //