diff --git a/internal/testprotos/fuzz/fuzz.pb.go b/internal/testprotos/fuzz/fuzz.pb.go
index 21c10c8..64f5b2c 100644
--- a/internal/testprotos/fuzz/fuzz.pb.go
+++ b/internal/testprotos/fuzz/fuzz.pb.go
@@ -1,10 +1,10 @@
-// Code generated by protoc-gen-go. DO NOT EDIT.
-// source: fuzz/fuzz.proto
-
 // Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: fuzz/fuzz.proto
+
 package fuzz
 
 import (
diff --git a/internal/testprotos/fuzz/fuzz.proto b/internal/testprotos/fuzz/fuzz.proto
index 6a88009..7db8d19 100644
--- a/internal/testprotos/fuzz/fuzz.proto
+++ b/internal/testprotos/fuzz/fuzz.proto
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+syntax = "proto2";
+
 package goproto.proto.fuzz;
 
 import "test/test.proto";
diff --git a/internal/testprotos/required/required.pb.go b/internal/testprotos/required/required.pb.go
index 0316970..e2b1b87 100644
--- a/internal/testprotos/required/required.pb.go
+++ b/internal/testprotos/required/required.pb.go
@@ -5,7 +5,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: required/required.proto
 
-package required
+package goproto_proto_testrequired
 
 import (
 	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
@@ -808,33 +808,38 @@
 
 var file_required_required_proto_rawDesc = []byte{
 	0x0a, 0x17, 0x72, 0x65, 0x71, 0x75, 0x69, 0x72, 0x65, 0x64, 0x2f, 0x72, 0x65, 0x71, 0x75, 0x69,
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+	0x05, 0x67, 0x72, 0x6f, 0x75, 0x70, 0x1a, 0x15, 0x0a, 0x05, 0x47, 0x72, 0x6f, 0x75, 0x70, 0x12,
+	0x0c, 0x0a, 0x01, 0x76, 0x18, 0x01, 0x20, 0x01, 0x28, 0x05, 0x52, 0x01, 0x76,
 }
 
 var (
@@ -851,27 +856,27 @@
 
 var file_required_required_proto_msgTypes = make([]protoimpl.MessageInfo, 17)
 var file_required_required_proto_goTypes = []interface{}{
-	(*Int32)(nil),       // 0: Int32
-	(*Int64)(nil),       // 1: Int64
-	(*Uint32)(nil),      // 2: Uint32
-	(*Uint64)(nil),      // 3: Uint64
-	(*Sint32)(nil),      // 4: Sint32
-	(*Sint64)(nil),      // 5: Sint64
-	(*Fixed32)(nil),     // 6: Fixed32
-	(*Fixed64)(nil),     // 7: Fixed64
-	(*Float)(nil),       // 8: Float
-	(*Double)(nil),      // 9: Double
-	(*Bool)(nil),        // 10: Bool
-	(*String)(nil),      // 11: String
-	(*Bytes)(nil),       // 12: Bytes
-	(*Message)(nil),     // 13: Message
-	(*Group)(nil),       // 14: Group
-	(*Message_M)(nil),   // 15: Message.M
-	(*Group_Group)(nil), // 16: Group.Group
+	(*Int32)(nil),       // 0: goproto.proto.testrequired.Int32
+	(*Int64)(nil),       // 1: goproto.proto.testrequired.Int64
+	(*Uint32)(nil),      // 2: goproto.proto.testrequired.Uint32
+	(*Uint64)(nil),      // 3: goproto.proto.testrequired.Uint64
+	(*Sint32)(nil),      // 4: goproto.proto.testrequired.Sint32
+	(*Sint64)(nil),      // 5: goproto.proto.testrequired.Sint64
+	(*Fixed32)(nil),     // 6: goproto.proto.testrequired.Fixed32
+	(*Fixed64)(nil),     // 7: goproto.proto.testrequired.Fixed64
+	(*Float)(nil),       // 8: goproto.proto.testrequired.Float
+	(*Double)(nil),      // 9: goproto.proto.testrequired.Double
+	(*Bool)(nil),        // 10: goproto.proto.testrequired.Bool
+	(*String)(nil),      // 11: goproto.proto.testrequired.String
+	(*Bytes)(nil),       // 12: goproto.proto.testrequired.Bytes
+	(*Message)(nil),     // 13: goproto.proto.testrequired.Message
+	(*Group)(nil),       // 14: goproto.proto.testrequired.Group
+	(*Message_M)(nil),   // 15: goproto.proto.testrequired.Message.M
+	(*Group_Group)(nil), // 16: goproto.proto.testrequired.Group.Group
 }
 var file_required_required_proto_depIdxs = []int32{
-	15, // 0: Message.v:type_name -> Message.M
-	16, // 1: Group.group:type_name -> Group.Group
+	15, // 0: goproto.proto.testrequired.Message.v:type_name -> goproto.proto.testrequired.Message.M
+	16, // 1: goproto.proto.testrequired.Group.group:type_name -> goproto.proto.testrequired.Group.Group
 	2,  // [2:2] is the sub-list for method output_type
 	2,  // [2:2] is the sub-list for method input_type
 	2,  // [2:2] is the sub-list for extension type_name
diff --git a/internal/testprotos/required/required.proto b/internal/testprotos/required/required.proto
index 23d70af..911c525 100644
--- a/internal/testprotos/required/required.proto
+++ b/internal/testprotos/required/required.proto
@@ -4,6 +4,8 @@
 
 syntax = "proto2";
 
+package goproto.proto.testrequired;
+
 message Int32 {
   required int32 v = 1;
 }