Regenerated test code for C#

6 files changed, 330 insertions, 295 deletions

diff --git a/csharp/src/Google.Protobuf.Test/TestProtos/MapUnittestProto3.cs b/csharp/src/Google.Protobuf.Test/TestProtos/MapUnittestProto3.cs
index 9c0518a3..b5151c54 100644
--- a/csharp/src/Google.Protobuf.Test/TestProtos/MapUnittestProto3.cs
+++ b/csharp/src/Google.Protobuf.Test/TestProtos/MapUnittestProto3.cs
@@ -1,5 +1,5 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
-// source: google/protobuf/map_unittest_proto3.proto
+// source: map_unittest_proto3.proto
 #pragma warning disable 1591, 0612, 3021
 #region Designer generated code
 
@@ -9,11 +9,11 @@ using pbr = global::Google.Protobuf.Reflection;
 using scg = global::System.Collections.Generic;
 namespace Google.Protobuf.TestProtos {
 
-  /// <summary>Holder for reflection information generated from google/protobuf/map_unittest_proto3.proto</summary>
+  /// <summary>Holder for reflection information generated from map_unittest_proto3.proto</summary>
   public static partial class MapUnittestProto3Reflection {
 
     #region Descriptor
-    /// <summary>File descriptor for google/protobuf/map_unittest_proto3.proto</summary>
+    /// <summary>File descriptor for map_unittest_proto3.proto</summary>
     public static pbr::FileDescriptor Descriptor {
       get { return descriptor; }
     }
@@ -22,130 +22,130 @@ namespace Google.Protobuf.TestProtos {
     static MapUnittestProto3Reflection() {
       byte[] descriptorData = global::System.Convert.FromBase64String(
           string.Concat(
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+            "eRILCgNrZXkYASABKAcSDQoFdmFsdWUYAiABKAc6AjgBGjgKFk1hcEZpeGVk",
+            "NjRGaXhlZDY0RW50cnkSCwoDa2V5GAEgASgGEg0KBXZhbHVlGAIgASgGOgI4",
+            "ARo6ChhNYXBTZml4ZWQzMlNmaXhlZDMyRW50cnkSCwoDa2V5GAEgASgPEg0K",
+            "BXZhbHVlGAIgASgPOgI4ARo6ChhNYXBTZml4ZWQ2NFNmaXhlZDY0RW50cnkS",
+            "CwoDa2V5GAEgASgQEg0KBXZhbHVlGAIgASgQOgI4ARo0ChJNYXBJbnQzMkZs",
+            "b2F0RW50cnkSCwoDa2V5GAEgASgFEg0KBXZhbHVlGAIgASgCOgI4ARo1ChNN",
+            "YXBJbnQzMkRvdWJsZUVudHJ5EgsKA2tleRgBIAEoBRINCgV2YWx1ZRgCIAEo",
+            "AToCOAEaMgoQTWFwQm9vbEJvb2xFbnRyeRILCgNrZXkYASABKAgSDQoFdmFs",
+            "dWUYAiABKAg6AjgBGjYKFE1hcFN0cmluZ1N0cmluZ0VudHJ5EgsKA2tleRgB",
+            "IAEoCRINCgV2YWx1ZRgCIAEoCToCOAEaNAoSTWFwSW50MzJCeXRlc0VudHJ5",
+            "EgsKA2tleRgBIAEoBRINCgV2YWx1ZRgCIAEoDDoCOAEaUAoRTWFwSW50MzJF",
+            "bnVtRW50cnkSCwoDa2V5GAEgASgFEioKBXZhbHVlGAIgASgOMhsucHJvdG9i",
+            "dWZfdW5pdHRlc3QzLk1hcEVudW06AjgBGmEKG01hcEludDMyRm9yZWlnbk1l",
+            "c3NhZ2VFbnRyeRILCgNrZXkYASABKAUSMQoFdmFsdWUYAiABKAsyIi5wcm90",
+            "b2J1Zl91bml0dGVzdDMuRm9yZWlnbk1lc3NhZ2U6AjgBIkIKEVRlc3RNYXBT",
+            "dWJtZXNzYWdlEi0KCHRlc3RfbWFwGAEgASgLMhsucHJvdG9idWZfdW5pdHRl",
+            "c3QzLlRlc3RNYXAivgEKDlRlc3RNZXNzYWdlTWFwElIKEW1hcF9pbnQzMl9t",
+            "ZXNzYWdlGAEgAygLMjcucHJvdG9idWZfdW5pdHRlc3QzLlRlc3RNZXNzYWdl",
+            "TWFwLk1hcEludDMyTWVzc2FnZUVudHJ5GlgKFE1hcEludDMyTWVzc2FnZUVu",
+            "dHJ5EgsKA2tleRgBIAEoBRIvCgV2YWx1ZRgCIAEoCzIgLnByb3RvYnVmX3Vu",
+            "aXR0ZXN0My5UZXN0QWxsVHlwZXM6AjgBIuUBCg9UZXN0U2FtZVR5cGVNYXAS",
+            "OwoEbWFwMRgBIAMoCzItLnByb3RvYnVmX3VuaXR0ZXN0My5UZXN0U2FtZVR5",
+            "cGVNYXAuTWFwMUVudHJ5EjsKBG1hcDIYAiADKAsyLS5wcm90b2J1Zl91bml0",
+            "dGVzdDMuVGVzdFNhbWVUeXBlTWFwLk1hcDJFbnRyeRorCglNYXAxRW50cnkS",
+            "CwoDa2V5GAEgASgFEg0KBXZhbHVlGAIgASgFOgI4ARorCglNYXAyRW50cnkS",
+            "CwoDa2V5GAEgASgFEg0KBXZhbHVlGAIgASgFOgI4ASL1EAoMVGVzdEFyZW5h",
+            "TWFwEkwKD21hcF9pbnQzMl9pbnQzMhgBIAMoCzIzLnByb3RvYnVmX3VuaXR0",
+            "ZXN0My5UZXN0QXJlbmFNYXAuTWFwSW50MzJJbnQzMkVudHJ5EkwKD21hcF9p",
+            "bnQ2NF9pbnQ2NBgCIAMoCzIzLnByb3RvYnVmX3VuaXR0ZXN0My5UZXN0QXJl",
+            "bmFNYXAuTWFwSW50NjRJbnQ2NEVudHJ5ElAKEW1hcF91aW50MzJfdWludDMy",
+            "GAMgAygLMjUucHJvdG9idWZfdW5pdHRlc3QzLlRlc3RBcmVuYU1hcC5NYXBV",
+            "aW50MzJVaW50MzJFbnRyeRJQChFtYXBfdWludDY0X3VpbnQ2NBgEIAMoCzI1",
+            "LnByb3RvYnVmX3VuaXR0ZXN0My5UZXN0QXJlbmFNYXAuTWFwVWludDY0VWlu",
+            "dDY0RW50cnkSUAoRbWFwX3NpbnQzMl9zaW50MzIYBSADKAsyNS5wcm90b2J1",
+            "Zl91bml0dGVzdDMuVGVzdEFyZW5hTWFwLk1hcFNpbnQzMlNpbnQzMkVudHJ5",
+            "ElAKEW1hcF9zaW50NjRfc2ludDY0GAYgAygLMjUucHJvdG9idWZfdW5pdHRl",
+            "c3QzLlRlc3RBcmVuYU1hcC5NYXBTaW50NjRTaW50NjRFbnRyeRJUChNtYXBf",
+            "Zml4ZWQzMl9maXhlZDMyGAcgAygLMjcucHJvdG9idWZfdW5pdHRlc3QzLlRl",
+            "c3RBcmVuYU1hcC5NYXBGaXhlZDMyRml4ZWQzMkVudHJ5ElQKE21hcF9maXhl",
+            "ZDY0X2ZpeGVkNjQYCCADKAsyNy5wcm90b2J1Zl91bml0dGVzdDMuVGVzdEFy",
+            "ZW5hTWFwLk1hcEZpeGVkNjRGaXhlZDY0RW50cnkSWAoVbWFwX3NmaXhlZDMy",
+            "X3NmaXhlZDMyGAkgAygLMjkucHJvdG9idWZfdW5pdHRlc3QzLlRlc3RBcmVu",
+            "YU1hcC5NYXBTZml4ZWQzMlNmaXhlZDMyRW50cnkSWAoVbWFwX3NmaXhlZDY0",
+            "X3NmaXhlZDY0GAogAygLMjkucHJvdG9idWZfdW5pdHRlc3QzLlRlc3RBcmVu",
+            "YU1hcC5NYXBTZml4ZWQ2NFNmaXhlZDY0RW50cnkSTAoPbWFwX2ludDMyX2Zs",
+            "b2F0GAsgAygLMjMucHJvdG9idWZfdW5pdHRlc3QzLlRlc3RBcmVuYU1hcC5N",
+            "YXBJbnQzMkZsb2F0RW50cnkSTgoQbWFwX2ludDMyX2RvdWJsZRgMIAMoCzI0",
+            "LnByb3RvYnVmX3VuaXR0ZXN0My5UZXN0QXJlbmFNYXAuTWFwSW50MzJEb3Vi",
+            "bGVFbnRyeRJICg1tYXBfYm9vbF9ib29sGA0gAygLMjEucHJvdG9idWZfdW5p",
+            "dHRlc3QzLlRlc3RBcmVuYU1hcC5NYXBCb29sQm9vbEVudHJ5EkoKDm1hcF9p",
+            "bnQzMl9lbnVtGA4gAygLMjIucHJvdG9idWZfdW5pdHRlc3QzLlRlc3RBcmVu",
+            "YU1hcC5NYXBJbnQzMkVudW1FbnRyeRJfChltYXBfaW50MzJfZm9yZWlnbl9t",
+            "ZXNzYWdlGA8gAygLMjwucHJvdG9idWZfdW5pdHRlc3QzLlRlc3RBcmVuYU1h",
+            "cC5NYXBJbnQzMkZvcmVpZ25NZXNzYWdlRW50cnkaNAoSTWFwSW50MzJJbnQz",
+            "MkVudHJ5EgsKA2tleRgBIAEoBRINCgV2YWx1ZRgCIAEoBToCOAEaNAoSTWFw",
+            "SW50NjRJbnQ2NEVudHJ5EgsKA2tleRgBIAEoAxINCgV2YWx1ZRgCIAEoAzoC",
+            "OAEaNgoUTWFwVWludDMyVWludDMyRW50cnkSCwoDa2V5GAEgASgNEg0KBXZh",
+            "bHVlGAIgASgNOgI4ARo2ChRNYXBVaW50NjRVaW50NjRFbnRyeRILCgNrZXkY",
+            "ASABKAQSDQoFdmFsdWUYAiABKAQ6AjgBGjYKFE1hcFNpbnQzMlNpbnQzMkVu",
+            "dHJ5EgsKA2tleRgBIAEoERINCgV2YWx1ZRgCIAEoEToCOAEaNgoUTWFwU2lu",
+            "dDY0U2ludDY0RW50cnkSCwoDa2V5GAEgASgSEg0KBXZhbHVlGAIgASgSOgI4",
+            "ARo4ChZNYXBGaXhlZDMyRml4ZWQzMkVudHJ5EgsKA2tleRgBIAEoBxINCgV2",
+            "YWx1ZRgCIAEoBzoCOAEaOAoWTWFwRml4ZWQ2NEZpeGVkNjRFbnRyeRILCgNr",
+            "ZXkYASABKAYSDQoFdmFsdWUYAiABKAY6AjgBGjoKGE1hcFNmaXhlZDMyU2Zp",
+            "eGVkMzJFbnRyeRILCgNrZXkYASABKA8SDQoFdmFsdWUYAiABKA86AjgBGjoK",
+            "GE1hcFNmaXhlZDY0U2ZpeGVkNjRFbnRyeRILCgNrZXkYASABKBASDQoFdmFs",
+            "dWUYAiABKBA6AjgBGjQKEk1hcEludDMyRmxvYXRFbnRyeRILCgNrZXkYASAB",
+            "KAUSDQoFdmFsdWUYAiABKAI6AjgBGjUKE01hcEludDMyRG91YmxlRW50cnkS",
+            "CwoDa2V5GAEgASgFEg0KBXZhbHVlGAIgASgBOgI4ARoyChBNYXBCb29sQm9v",
+            "bEVudHJ5EgsKA2tleRgBIAEoCBINCgV2YWx1ZRgCIAEoCDoCOAEaUAoRTWFw",
+            "SW50MzJFbnVtRW50cnkSCwoDa2V5GAEgASgFEioKBXZhbHVlGAIgASgOMhsu",
+            "cHJvdG9idWZfdW5pdHRlc3QzLk1hcEVudW06AjgBGmEKG01hcEludDMyRm9y",
+            "ZWlnbk1lc3NhZ2VFbnRyeRILCgNrZXkYASABKAUSMQoFdmFsdWUYAiABKAsy",
+            "Ii5wcm90b2J1Zl91bml0dGVzdDMuRm9yZWlnbk1lc3NhZ2U6AjgBIuYBCh9N",
+            "ZXNzYWdlQ29udGFpbmluZ0VudW1DYWxsZWRUeXBlEksKBHR5cGUYASADKAsy",
+            "PS5wcm90b2J1Zl91bml0dGVzdDMuTWVzc2FnZUNvbnRhaW5pbmdFbnVtQ2Fs",
+            "bGVkVHlwZS5UeXBlRW50cnkaYAoJVHlwZUVudHJ5EgsKA2tleRgBIAEoBRJC",
+            "CgV2YWx1ZRgCIAEoCzIzLnByb3RvYnVmX3VuaXR0ZXN0My5NZXNzYWdlQ29u",
+            "dGFpbmluZ0VudW1DYWxsZWRUeXBlOgI4ASIUCgRUeXBlEgwKCFRZUEVfRk9P",
+            "EAAingEKH01lc3NhZ2VDb250YWluaW5nTWFwQ2FsbGVkRW50cnkSTQoFZW50",
+            "cnkYASADKAsyPi5wcm90b2J1Zl91bml0dGVzdDMuTWVzc2FnZUNvbnRhaW5p",
+            "bmdNYXBDYWxsZWRFbnRyeS5FbnRyeUVudHJ5GiwKCkVudHJ5RW50cnkSCwoD",
+            "a2V5GAEgASgFEg0KBXZhbHVlGAIgASgFOgI4ASo/CgdNYXBFbnVtEhAKDE1B",
+            "UF9FTlVNX0ZPTxAAEhAKDE1BUF9FTlVNX0JBUhABEhAKDE1BUF9FTlVNX0JB",
+            "WhACQiD4AQGqAhpHb29nbGUuUHJvdG9idWYuVGVzdFByb3Rvc2IGcHJvdG8z"));
       descriptor = pbr::FileDescriptor.FromGeneratedCode(descriptorData,
           new pbr::FileDescriptor[] { global::Google.Protobuf.TestProtos.UnittestProto3Reflection.Descriptor, },
           new pbr::GeneratedClrTypeInfo(new[] {typeof(global::Google.Protobuf.TestProtos.MapEnum), }, new pbr::GeneratedClrTypeInfo[] {
diff --git a/csharp/src/Google.Protobuf.Test/TestProtos/TestMessagesProto3.cs b/csharp/src/Google.Protobuf.Test/TestProtos/TestMessagesProto3.cs
index 6607be7a..45850bb0 100644
--- a/csharp/src/Google.Protobuf.Test/TestProtos/TestMessagesProto3.cs
+++ b/csharp/src/Google.Protobuf.Test/TestProtos/TestMessagesProto3.cs
@@ -27,7 +27,7 @@ namespace ProtobufTestMessages.Proto3 {
             "dWYvYW55LnByb3RvGh5nb29nbGUvcHJvdG9idWYvZHVyYXRpb24ucHJvdG8a",
             "IGdvb2dsZS9wcm90b2J1Zi9maWVsZF9tYXNrLnByb3RvGhxnb29nbGUvcHJv",
             "dG9idWYvc3RydWN0LnByb3RvGh9nb29nbGUvcHJvdG9idWYvdGltZXN0YW1w",
-            "LnByb3RvGh5nb29nbGUvcHJvdG9idWYvd3JhcHBlcnMucHJvdG8irDsKElRl",
+            "LnByb3RvGh5nb29nbGUvcHJvdG9idWYvd3JhcHBlcnMucHJvdG8itDsKElRl",
             "c3RBbGxUeXBlc1Byb3RvMxIWCg5vcHRpb25hbF9pbnQzMhgBIAEoBRIWCg5v",
             "cHRpb25hbF9pbnQ2NBgCIAEoAxIXCg9vcHRpb25hbF91aW50MzIYAyABKA0S",
             "FwoPb3B0aW9uYWxfdWludDY0GAQgASgEEhcKD29wdGlvbmFsX3NpbnQzMhgF",
@@ -196,11 +196,11 @@ namespace ProtobufTestMessages.Proto3 {
             "Z0ZvcmVpZ25FbnVtRW50cnkSCwoDa2V5GAEgASgJEjkKBXZhbHVlGAIgASgO",
             "MioucHJvdG9idWZfdGVzdF9tZXNzYWdlcy5wcm90bzMuRm9yZWlnbkVudW06",
             "AjgBIjkKCk5lc3RlZEVudW0SBwoDRk9PEAASBwoDQkFSEAESBwoDQkFaEAIS",
-            "EAoDTkVHEP///////////wFCDQoLb25lb2ZfZmllbGQiGwoORm9yZWlnbk1l",
-            "c3NhZ2USCQoBYxgBIAEoBSpACgtGb3JlaWduRW51bRIPCgtGT1JFSUdOX0ZP",
-            "TxAAEg8KC0ZPUkVJR05fQkFSEAESDwoLRk9SRUlHTl9CQVoQAkI4Cihjb20u",
-            "Z29vZ2xlLnByb3RvYnVmX3Rlc3RfbWVzc2FnZXMucHJvdG8zSAH4AQGiAgZQ",
-            "cm90bzNiBnByb3RvMw=="));
+            "EAoDTkVHEP///////////wFCDQoLb25lb2ZfZmllbGRKBgj1AxD/AyIbCg5G",
+            "b3JlaWduTWVzc2FnZRIJCgFjGAEgASgFKkAKC0ZvcmVpZ25FbnVtEg8KC0ZP",
+            "UkVJR05fRk9PEAASDwoLRk9SRUlHTl9CQVIQARIPCgtGT1JFSUdOX0JBWhAC",
+            "QjgKKGNvbS5nb29nbGUucHJvdG9idWZfdGVzdF9tZXNzYWdlcy5wcm90bzNI",
+            "AfgBAaICBlByb3RvM2IGcHJvdG8z"));
       descriptor = pbr::FileDescriptor.FromGeneratedCode(descriptorData,
           new pbr::FileDescriptor[] { global::Google.Protobuf.WellKnownTypes.AnyReflection.Descriptor, global::Google.Protobuf.WellKnownTypes.DurationReflection.Descriptor, global::Google.Protobuf.WellKnownTypes.FieldMaskReflection.Descriptor, global::Google.Protobuf.WellKnownTypes.StructReflection.Descriptor, global::Google.Protobuf.WellKnownTypes.TimestampReflection.Descriptor, global::Google.Protobuf.WellKnownTypes.WrappersReflection.Descriptor, },
           new pbr::GeneratedClrTypeInfo(new[] {typeof(global::ProtobufTestMessages.Proto3.ForeignEnum), }, new pbr::GeneratedClrTypeInfo[] {
@@ -2808,7 +2808,10 @@ namespace ProtobufTestMessages.Proto3 {
           OneofUint32 = other.OneofUint32;
           break;
         case OneofFieldOneofCase.OneofNestedMessage:
-          OneofNestedMessage = other.OneofNestedMessage;
+          if (OneofNestedMessage == null) {
+            OneofNestedMessage = new global::ProtobufTestMessages.Proto3.TestAllTypesProto3.Types.NestedMessage();
+          }
+          OneofNestedMessage.MergeFrom(other.OneofNestedMessage);
           break;
         case OneofFieldOneofCase.OneofString:
           OneofString = other.OneofString;
diff --git a/csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportProto3.cs b/csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportProto3.cs
index f6df4e87..22016f83 100644
--- a/csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportProto3.cs
+++ b/csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportProto3.cs
@@ -1,5 +1,5 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
-// source: google/protobuf/unittest_import_proto3.proto
+// source: unittest_import_proto3.proto
 #pragma warning disable 1591, 0612, 3021
 #region Designer generated code
 
@@ -9,11 +9,11 @@ using pbr = global::Google.Protobuf.Reflection;
 using scg = global::System.Collections.Generic;
 namespace Google.Protobuf.TestProtos {
 
-  /// <summary>Holder for reflection information generated from google/protobuf/unittest_import_proto3.proto</summary>
+  /// <summary>Holder for reflection information generated from unittest_import_proto3.proto</summary>
   public static partial class UnittestImportProto3Reflection {
 
     #region Descriptor
-    /// <summary>File descriptor for google/protobuf/unittest_import_proto3.proto</summary>
+    /// <summary>File descriptor for unittest_import_proto3.proto</summary>
     public static pbr::FileDescriptor Descriptor {
       get { return descriptor; }
     }
@@ -22,14 +22,13 @@ namespace Google.Protobuf.TestProtos {
     static UnittestImportProto3Reflection() {
       byte[] descriptorData = global::System.Convert.FromBase64String(
           string.Concat(
-            "Cixnb29nbGUvcHJvdG9idWYvdW5pdHRlc3RfaW1wb3J0X3Byb3RvMy5wcm90",
-            "bxIYcHJvdG9idWZfdW5pdHRlc3RfaW1wb3J0GjNnb29nbGUvcHJvdG9idWYv",
-            "dW5pdHRlc3RfaW1wb3J0X3B1YmxpY19wcm90bzMucHJvdG8iGgoNSW1wb3J0",
-            "TWVzc2FnZRIJCgFkGAEgASgFKlkKCkltcG9ydEVudW0SGwoXSU1QT1JUX0VO",
-            "VU1fVU5TUEVDSUZJRUQQABIOCgpJTVBPUlRfRk9PEAcSDgoKSU1QT1JUX0JB",
-            "UhAIEg4KCklNUE9SVF9CQVoQCUI8Chhjb20uZ29vZ2xlLnByb3RvYnVmLnRl",
-            "c3RIAfgBAaoCGkdvb2dsZS5Qcm90b2J1Zi5UZXN0UHJvdG9zUABiBnByb3Rv",
-            "Mw=="));
+            "Chx1bml0dGVzdF9pbXBvcnRfcHJvdG8zLnByb3RvEhhwcm90b2J1Zl91bml0",
+            "dGVzdF9pbXBvcnQaI3VuaXR0ZXN0X2ltcG9ydF9wdWJsaWNfcHJvdG8zLnBy",
+            "b3RvIhoKDUltcG9ydE1lc3NhZ2USCQoBZBgBIAEoBSpZCgpJbXBvcnRFbnVt",
+            "EhsKF0lNUE9SVF9FTlVNX1VOU1BFQ0lGSUVEEAASDgoKSU1QT1JUX0ZPTxAH",
+            "Eg4KCklNUE9SVF9CQVIQCBIOCgpJTVBPUlRfQkFaEAlCPAoYY29tLmdvb2ds",
+            "ZS5wcm90b2J1Zi50ZXN0SAH4AQGqAhpHb29nbGUuUHJvdG9idWYuVGVzdFBy",
+            "b3Rvc1AAYgZwcm90bzM="));
       descriptor = pbr::FileDescriptor.FromGeneratedCode(descriptorData,
           new pbr::FileDescriptor[] { global::Google.Protobuf.TestProtos.UnittestImportPublicProto3Reflection.Descriptor, },
           new pbr::GeneratedClrTypeInfo(new[] {typeof(global::Google.Protobuf.TestProtos.ImportEnum), }, new pbr::GeneratedClrTypeInfo[] {
diff --git a/csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportPublicProto3.cs b/csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportPublicProto3.cs
index 67b8edf4..a6a2af82 100644
--- a/csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportPublicProto3.cs
+++ b/csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportPublicProto3.cs
@@ -1,5 +1,5 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
-// source: google/protobuf/unittest_import_public_proto3.proto
+// source: unittest_import_public_proto3.proto
 #pragma warning disable 1591, 0612, 3021
 #region Designer generated code
 
@@ -9,11 +9,11 @@ using pbr = global::Google.Protobuf.Reflection;
 using scg = global::System.Collections.Generic;
 namespace Google.Protobuf.TestProtos {
 
-  /// <summary>Holder for reflection information generated from google/protobuf/unittest_import_public_proto3.proto</summary>
+  /// <summary>Holder for reflection information generated from unittest_import_public_proto3.proto</summary>
   public static partial class UnittestImportPublicProto3Reflection {
 
     #region Descriptor
-    /// <summary>File descriptor for google/protobuf/unittest_import_public_proto3.proto</summary>
+    /// <summary>File descriptor for unittest_import_public_proto3.proto</summary>
     public static pbr::FileDescriptor Descriptor {
       get { return descriptor; }
     }
@@ -22,10 +22,10 @@ namespace Google.Protobuf.TestProtos {
     static UnittestImportPublicProto3Reflection() {
       byte[] descriptorData = global::System.Convert.FromBase64String(
           string.Concat(
-            "CjNnb29nbGUvcHJvdG9idWYvdW5pdHRlc3RfaW1wb3J0X3B1YmxpY19wcm90",
-            "bzMucHJvdG8SGHByb3RvYnVmX3VuaXR0ZXN0X2ltcG9ydCIgChNQdWJsaWNJ",
-            "bXBvcnRNZXNzYWdlEgkKAWUYASABKAVCNwoYY29tLmdvb2dsZS5wcm90b2J1",
-            "Zi50ZXN0qgIaR29vZ2xlLlByb3RvYnVmLlRlc3RQcm90b3NiBnByb3RvMw=="));
+            "CiN1bml0dGVzdF9pbXBvcnRfcHVibGljX3Byb3RvMy5wcm90bxIYcHJvdG9i",
+            "dWZfdW5pdHRlc3RfaW1wb3J0IiAKE1B1YmxpY0ltcG9ydE1lc3NhZ2USCQoB",
+            "ZRgBIAEoBUI3Chhjb20uZ29vZ2xlLnByb3RvYnVmLnRlc3SqAhpHb29nbGUu",
+            "UHJvdG9idWYuVGVzdFByb3Rvc2IGcHJvdG8z"));
       descriptor = pbr::FileDescriptor.FromGeneratedCode(descriptorData,
           new pbr::FileDescriptor[] { },
           new pbr::GeneratedClrTypeInfo(null, new pbr::GeneratedClrTypeInfo[] {
diff --git a/csharp/src/Google.Protobuf.Test/TestProtos/UnittestProto3.cs b/csharp/src/Google.Protobuf.Test/TestProtos/UnittestProto3.cs
index c11ab84d..3176be72 100644
--- a/csharp/src/Google.Protobuf.Test/TestProtos/UnittestProto3.cs
+++ b/csharp/src/Google.Protobuf.Test/TestProtos/UnittestProto3.cs
@@ -1,5 +1,5 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
-// source: google/protobuf/unittest_proto3.proto
+// source: unittest_proto3.proto
 #pragma warning disable 1591, 0612, 3021
 #region Designer generated code
 
@@ -9,11 +9,11 @@ using pbr = global::Google.Protobuf.Reflection;
 using scg = global::System.Collections.Generic;
 namespace Google.Protobuf.TestProtos {
 
-  /// <summary>Holder for reflection information generated from google/protobuf/unittest_proto3.proto</summary>
+  /// <summary>Holder for reflection information generated from unittest_proto3.proto</summary>
   public static partial class UnittestProto3Reflection {
 
     #region Descriptor
-    /// <summary>File descriptor for google/protobuf/unittest_proto3.proto</summary>
+    /// <summary>File descriptor for unittest_proto3.proto</summary>
     public static pbr::FileDescriptor Descriptor {
       get { return descriptor; }
     }
@@ -22,135 +22,135 @@ namespace Google.Protobuf.TestProtos {
     static UnittestProto3Reflection() {
       byte[] descriptorData = global::System.Convert.FromBase64String(
           string.Concat(
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+            "DQoLQmFyUmVzcG9uc2UqWQoLRm9yZWlnbkVudW0SFwoTRk9SRUlHTl9VTlNQ",
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+            "U1RfRU5VTV9XSVRIX0RVUF9WQUxVRV9VTlNQRUNJRklFRBAAEggKBEZPTzEQ",
+            "ARIICgRCQVIxEAISBwoDQkFaEAMSCAoERk9PMhABEggKBEJBUjIQAhoCEAEq",
+            "nQEKDlRlc3RTcGFyc2VFbnVtEiAKHFRFU1RfU1BBUlNFX0VOVU1fVU5TUEVD",
+            "SUZJRUQQABIMCghTUEFSU0VfQRB7Eg4KCFNQQVJTRV9CEKbnAxIPCghTUEFS",
+            "U0VfQxCysYAGEhUKCFNQQVJTRV9EEPH//////////wESFQoIU1BBUlNFX0UQ",
+            "tN78////////ARIMCghTUEFSU0VfRxACMp0BCgtUZXN0U2VydmljZRJGCgNG",
+            "b28SHi5wcm90b2J1Zl91bml0dGVzdDMuRm9vUmVxdWVzdBofLnByb3RvYnVm",
+            "X3VuaXR0ZXN0My5Gb29SZXNwb25zZRJGCgNCYXISHi5wcm90b2J1Zl91bml0",
+            "dGVzdDMuQmFyUmVxdWVzdBofLnByb3RvYnVmX3VuaXR0ZXN0My5CYXJSZXNw",
+            "b25zZUI6Qg1Vbml0dGVzdFByb3RvSAGAAQGIAQGQAQH4AQGqAhpHb29nbGUu",
+            "UHJvdG9idWYuVGVzdFByb3Rvc2IGcHJvdG8z"));
       descriptor = pbr::FileDescriptor.FromGeneratedCode(descriptorData,
           new pbr::FileDescriptor[] { global::Google.Protobuf.TestProtos.UnittestImportProto3Reflection.Descriptor, },
           new pbr::GeneratedClrTypeInfo(new[] {typeof(global::Google.Protobuf.TestProtos.ForeignEnum), typeof(global::Google.Protobuf.TestProtos.TestEnumWithDupValue), typeof(global::Google.Protobuf.TestProtos.TestSparseEnum), }, new pbr::GeneratedClrTypeInfo[] {
@@ -1337,7 +1337,10 @@ namespace Google.Protobuf.TestProtos {
           OneofUint32 = other.OneofUint32;
           break;
         case OneofFieldOneofCase.OneofNestedMessage:
-          OneofNestedMessage = other.OneofNestedMessage;
+          if (OneofNestedMessage == null) {
+            OneofNestedMessage = new global::Google.Protobuf.TestProtos.TestAllTypes.Types.NestedMessage();
+          }
+          OneofNestedMessage.MergeFrom(other.OneofNestedMessage);
           break;
         case OneofFieldOneofCase.OneofString:
           OneofString = other.OneofString;
@@ -5066,7 +5069,10 @@ namespace Google.Protobuf.TestProtos {
           FooString = other.FooString;
           break;
         case FooOneofCase.FooMessage:
-          FooMessage = other.FooMessage;
+          if (FooMessage == null) {
+            FooMessage = new global::Google.Protobuf.TestProtos.TestAllTypes();
+          }
+          FooMessage.MergeFrom(other.FooMessage);
           break;
       }
 
diff --git a/csharp/src/Google.Protobuf.Test/TestProtos/UnittestWellKnownTypes.cs b/csharp/src/Google.Protobuf.Test/TestProtos/UnittestWellKnownTypes.cs
index 2c7f0e0e..9c415d6c 100644
--- a/csharp/src/Google.Protobuf.Test/TestProtos/UnittestWellKnownTypes.cs
+++ b/csharp/src/Google.Protobuf.Test/TestProtos/UnittestWellKnownTypes.cs
@@ -1890,31 +1890,58 @@ namespace Google.Protobuf.TestProtos {
       }
       switch (other.OneofFieldCase) {
         case OneofFieldOneofCase.AnyField:
-          AnyField = other.AnyField;
+          if (AnyField == null) {
+            AnyField = new global::Google.Protobuf.WellKnownTypes.Any();
+          }
+          AnyField.MergeFrom(other.AnyField);
           break;
         case OneofFieldOneofCase.ApiField:
-          ApiField = other.ApiField;
+          if (ApiField == null) {
+            ApiField = new global::Google.Protobuf.WellKnownTypes.Api();
+          }
+          ApiField.MergeFrom(other.ApiField);
           break;
         case OneofFieldOneofCase.DurationField:
-          DurationField = other.DurationField;
+          if (DurationField == null) {
+            DurationField = new global::Google.Protobuf.WellKnownTypes.Duration();
+          }
+          DurationField.MergeFrom(other.DurationField);
           break;
         case OneofFieldOneofCase.EmptyField:
-          EmptyField = other.EmptyField;
+          if (EmptyField == null) {
+            EmptyField = new global::Google.Protobuf.WellKnownTypes.Empty();
+          }
+          EmptyField.MergeFrom(other.EmptyField);
           break;
         case OneofFieldOneofCase.FieldMaskField:
-          FieldMaskField = other.FieldMaskField;
+          if (FieldMaskField == null) {
+            FieldMaskField = new global::Google.Protobuf.WellKnownTypes.FieldMask();
+          }
+          FieldMaskField.MergeFrom(other.FieldMaskField);
           break;
         case OneofFieldOneofCase.SourceContextField:
-          SourceContextField = other.SourceContextField;
+          if (SourceContextField == null) {
+            SourceContextField = new global::Google.Protobuf.WellKnownTypes.SourceContext();
+          }
+          SourceContextField.MergeFrom(other.SourceContextField);
           break;
         case OneofFieldOneofCase.StructField:
-          StructField = other.StructField;
+          if (StructField == null) {
+            StructField = new global::Google.Protobuf.WellKnownTypes.Struct();
+          }
+          StructField.MergeFrom(other.StructField);
           break;
         case OneofFieldOneofCase.TimestampField:
-          TimestampField = other.TimestampField;
+          if (TimestampField == null) {
+            TimestampField = new global::Google.Protobuf.WellKnownTypes.Timestamp();
+          }
+          TimestampField.MergeFrom(other.TimestampField);
           break;
         case OneofFieldOneofCase.TypeField:
-          TypeField = other.TypeField;
+          if (TypeField == null) {
+            TypeField = new global::Google.Protobuf.WellKnownTypes.Type();
+          }
+          TypeField.MergeFrom(other.TypeField);
           break;
         case OneofFieldOneofCase.DoubleField:
           DoubleField = other.DoubleField;