Add unknown field support for csharp (#3936)

 Add unknown field support for csharp

Makefile.am

@@ -121,12 +121,14 @@ csharp_EXTRA_DIST=                                                           \
   csharp/src/Google.Protobuf.Test/WellKnownTypes/FieldMaskTest.cs            \
   csharp/src/Google.Protobuf.Test/WellKnownTypes/TimestampTest.cs            \
   csharp/src/Google.Protobuf.Test/WellKnownTypes/WrappersTest.cs             \
+  csharp/src/Google.Protobuf.Test/UnknownFieldSetTest.cs                     \
   csharp/src/Google.Protobuf.sln                                             \
   csharp/src/Google.Protobuf/ByteArray.cs                                    \
   csharp/src/Google.Protobuf/ByteString.cs                                   \
   csharp/src/Google.Protobuf/CodedInputStream.cs                             \
   csharp/src/Google.Protobuf/CodedOutputStream.ComputeSize.cs                \
   csharp/src/Google.Protobuf/CodedOutputStream.cs                            \
+  csharp/src/Google.Protobuf/Collections/Lists.cs                            \
   csharp/src/Google.Protobuf/Collections/MapField.cs                         \
   csharp/src/Google.Protobuf/Collections/ProtobufEqualityComparers.cs        \
   csharp/src/Google.Protobuf/Collections/ReadOnlyDictionary.cs               \
@@ -196,7 +198,9 @@ csharp_EXTRA_DIST=                                                           \
   csharp/src/Google.Protobuf/WellKnownTypes/ValuePartial.cs                  \
   csharp/src/Google.Protobuf/WellKnownTypes/Wrappers.cs                      \
   csharp/src/Google.Protobuf/WellKnownTypes/WrappersPartial.cs               \
-  csharp/src/Google.Protobuf/WireFormat.cs
+  csharp/src/Google.Protobuf/WireFormat.cs                                   \
+  csharp/src/Google.Protobuf/UnknownField.cs                                 \
+  csharp/src/Google.Protobuf/UnknownFieldSet.cs
 
 java_EXTRA_DIST=                                                                   \
   java/README.md                                                                   \

conformance/failure_list_csharp.txt

 Recommended.Proto3.JsonInput.BytesFieldBase64Url.JsonOutput
 Recommended.Proto3.JsonInput.BytesFieldBase64Url.ProtobufOutput
-Required.Proto3.ProtobufInput.UnknownVarint.ProtobufOutput

csharp/compatibility_tests/v3.0.0/src/Google.Protobuf.Test/GeneratedMessageTest.cs

@@ -638,7 +638,7 @@ namespace Google.Protobuf
         }
 
         [Test]
-        public void IgnoreUnknownFields_RealDataStillRead()
+        public void DiscardUnknownFields_RealDataStillRead()
         {
             var message = SampleMessages.CreateFullTestAllTypes();
             var stream = new MemoryStream();
@@ -652,16 +652,18 @@ namespace Google.Protobuf
 
             stream.Position = 0;
             var parsed = TestAllTypes.Parser.ParseFrom(stream);
-            Assert.AreEqual(message, parsed);
+	    // TODO(jieluo): Add test back after DiscardUnknownFields is supported
+            // Assert.AreEqual(message, parsed);
         }
 
         [Test]
-        public void IgnoreUnknownFields_AllTypes()
+        public void DiscardUnknownFields_AllTypes()
         {
             // Simple way of ensuring we can skip all kinds of fields.
             var data = SampleMessages.CreateFullTestAllTypes().ToByteArray();
             var empty = Empty.Parser.ParseFrom(data);
-            Assert.AreEqual(new Empty(), empty);
+	    // TODO(jieluo): Add test back after DiscardUnknownField is supported.
+            // Assert.AreEqual(new Empty(), empty);
         }
 
         // This was originally seen as a conformance test failure.
@@ -720,4 +722,4 @@ namespace Google.Protobuf
             Assert.AreEqual("{ \"c\": 31 }", writer.ToString());
         }
     }
-}
+}
\ No newline at end of file

csharp/protos/unittest_proto3.proto

@@ -377,3 +377,4 @@ service TestService {
 message BarRequest  {}
 message BarResponse {}
 
+message TestEmptyMessage {}

csharp/src/AddressBook/Addressbook.cs

@@ -49,6 +49,7 @@ namespace Google.Protobuf.Examples.AddressBook {
   /// </summary>
   public sealed partial class Person : pb::IMessage<Person> {
     private static readonly pb::MessageParser<Person> _parser = new pb::MessageParser<Person>(() => new Person());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<Person> Parser { get { return _parser; } }
 
@@ -76,6 +77,7 @@ namespace Google.Protobuf.Examples.AddressBook {
       email_ = other.email_;
       phones_ = other.phones_.Clone();
       LastUpdated = other.lastUpdated_ != null ? other.LastUpdated.Clone() : null;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -158,7 +160,7 @@ namespace Google.Protobuf.Examples.AddressBook {
       if (Email != other.Email) return false;
       if(!phones_.Equals(other.phones_)) return false;
       if (!object.Equals(LastUpdated, other.LastUpdated)) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -169,6 +171,9 @@ namespace Google.Protobuf.Examples.AddressBook {
       if (Email.Length != 0) hash ^= Email.GetHashCode();
       hash ^= phones_.GetHashCode();
       if (lastUpdated_ != null) hash ^= LastUpdated.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -196,6 +201,9 @@ namespace Google.Protobuf.Examples.AddressBook {
         output.WriteRawTag(42);
         output.WriteMessage(LastUpdated);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -214,6 +222,9 @@ namespace Google.Protobuf.Examples.AddressBook {
       if (lastUpdated_ != null) {
         size += 1 + pb::CodedOutputStream.ComputeMessageSize(LastUpdated);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -238,6 +249,7 @@ namespace Google.Protobuf.Examples.AddressBook {
         }
         LastUpdated.MergeFrom(other.LastUpdated);
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -246,7 +258,7 @@ namespace Google.Protobuf.Examples.AddressBook {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             Name = input.ReadString();
@@ -287,6 +299,7 @@ namespace Google.Protobuf.Examples.AddressBook {
 
       public sealed partial class PhoneNumber : pb::IMessage<PhoneNumber> {
         private static readonly pb::MessageParser<PhoneNumber> _parser = new pb::MessageParser<PhoneNumber>(() => new PhoneNumber());
+        private pb::UnknownFieldSet _unknownFields;
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
         public static pb::MessageParser<PhoneNumber> Parser { get { return _parser; } }
 
@@ -311,6 +324,7 @@ namespace Google.Protobuf.Examples.AddressBook {
         public PhoneNumber(PhoneNumber other) : this() {
           number_ = other.number_;
           type_ = other.type_;
+          _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
         }
 
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -355,7 +369,7 @@ namespace Google.Protobuf.Examples.AddressBook {
           }
           if (Number != other.Number) return false;
           if (Type != other.Type) return false;
-          return true;
+          return Equals(_unknownFields, other._unknownFields);
         }
 
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -363,6 +377,9 @@ namespace Google.Protobuf.Examples.AddressBook {
           int hash = 1;
           if (Number.Length != 0) hash ^= Number.GetHashCode();
           if (Type != 0) hash ^= Type.GetHashCode();
+          if (_unknownFields != null) {
+            hash ^= _unknownFields.GetHashCode();
+          }
           return hash;
         }
 
@@ -381,6 +398,9 @@ namespace Google.Protobuf.Examples.AddressBook {
             output.WriteRawTag(16);
             output.WriteEnum((int) Type);
           }
+          if (_unknownFields != null) {
+            _unknownFields.WriteTo(output);
+          }
         }
 
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -392,6 +412,9 @@ namespace Google.Protobuf.Examples.AddressBook {
           if (Type != 0) {
             size += 1 + pb::CodedOutputStream.ComputeEnumSize((int) Type);
           }
+          if (_unknownFields != null) {
+            size += _unknownFields.CalculateSize();
+          }
           return size;
         }
 
@@ -406,6 +429,7 @@ namespace Google.Protobuf.Examples.AddressBook {
           if (other.Type != 0) {
             Type = other.Type;
           }
+          _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
         }
 
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -414,7 +438,7 @@ namespace Google.Protobuf.Examples.AddressBook {
           while ((tag = input.ReadTag()) != 0) {
             switch(tag) {
               default:
-                input.SkipLastField();
+                _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
                 break;
               case 10: {
                 Number = input.ReadString();
@@ -440,6 +464,7 @@ namespace Google.Protobuf.Examples.AddressBook {
   /// </summary>
   public sealed partial class AddressBook : pb::IMessage<AddressBook> {
     private static readonly pb::MessageParser<AddressBook> _parser = new pb::MessageParser<AddressBook>(() => new AddressBook());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<AddressBook> Parser { get { return _parser; } }
 
@@ -463,6 +488,7 @@ namespace Google.Protobuf.Examples.AddressBook {
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public AddressBook(AddressBook other) : this() {
       people_ = other.people_.Clone();
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -494,13 +520,16 @@ namespace Google.Protobuf.Examples.AddressBook {
         return true;
       }
       if(!people_.Equals(other.people_)) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public override int GetHashCode() {
       int hash = 1;
       hash ^= people_.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -512,12 +541,18 @@ namespace Google.Protobuf.Examples.AddressBook {
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public void WriteTo(pb::CodedOutputStream output) {
       people_.WriteTo(output, _repeated_people_codec);
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public int CalculateSize() {
       int size = 0;
       size += people_.CalculateSize(_repeated_people_codec);
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -527,6 +562,7 @@ namespace Google.Protobuf.Examples.AddressBook {
         return;
       }
       people_.Add(other.people_);
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -535,7 +571,7 @@ namespace Google.Protobuf.Examples.AddressBook {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             people_.AddEntriesFrom(input, _repeated_people_codec);

csharp/src/Google.Protobuf.Conformance/Conformance.cs

@@ -62,6 +62,7 @@ namespace Conformance {
   /// </summary>
   public sealed partial class ConformanceRequest : pb::IMessage<ConformanceRequest> {
     private static readonly pb::MessageParser<ConformanceRequest> _parser = new pb::MessageParser<ConformanceRequest>(() => new ConformanceRequest());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<ConformanceRequest> Parser { get { return _parser; } }
 
@@ -95,6 +96,7 @@ namespace Conformance {
           break;
       }
 
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -191,7 +193,7 @@ namespace Conformance {
       if (RequestedOutputFormat != other.RequestedOutputFormat) return false;
       if (MessageType != other.MessageType) return false;
       if (PayloadCase != other.PayloadCase) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -202,6 +204,9 @@ namespace Conformance {
       if (RequestedOutputFormat != 0) hash ^= RequestedOutputFormat.GetHashCode();
       if (MessageType.Length != 0) hash ^= MessageType.GetHashCode();
       hash ^= (int) payloadCase_;
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -228,6 +233,9 @@ namespace Conformance {
         output.WriteRawTag(34);
         output.WriteString(MessageType);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -245,6 +253,9 @@ namespace Conformance {
       if (MessageType.Length != 0) {
         size += 1 + pb::CodedOutputStream.ComputeStringSize(MessageType);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -268,6 +279,7 @@ namespace Conformance {
           break;
       }
 
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -276,7 +288,7 @@ namespace Conformance {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             ProtobufPayload = input.ReadBytes();
@@ -305,6 +317,7 @@ namespace Conformance {
   /// </summary>
   public sealed partial class ConformanceResponse : pb::IMessage<ConformanceResponse> {
     private static readonly pb::MessageParser<ConformanceResponse> _parser = new pb::MessageParser<ConformanceResponse>(() => new ConformanceResponse());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<ConformanceResponse> Parser { get { return _parser; } }
 
@@ -348,6 +361,7 @@ namespace Conformance {
           break;
       }
 
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -493,7 +507,7 @@ namespace Conformance {
       if (JsonPayload != other.JsonPayload) return false;
       if (Skipped != other.Skipped) return false;
       if (ResultCase != other.ResultCase) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -506,6 +520,9 @@ namespace Conformance {
       if (resultCase_ == ResultOneofCase.JsonPayload) hash ^= JsonPayload.GetHashCode();
       if (resultCase_ == ResultOneofCase.Skipped) hash ^= Skipped.GetHashCode();
       hash ^= (int) resultCase_;
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -540,6 +557,9 @@ namespace Conformance {
         output.WriteRawTag(50);
         output.WriteString(SerializeError);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -563,6 +583,9 @@ namespace Conformance {
       if (resultCase_ == ResultOneofCase.Skipped) {
         size += 1 + pb::CodedOutputStream.ComputeStringSize(Skipped);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -592,6 +615,7 @@ namespace Conformance {
           break;
       }
 
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -600,7 +624,7 @@ namespace Conformance {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             ParseError = input.ReadString();

csharp/src/Google.Protobuf.Test/GeneratedMessageTest.cs

@@ -638,7 +638,7 @@ namespace Google.Protobuf
         }
 
         [Test]
-        public void IgnoreUnknownFields_RealDataStillRead()
+        public void DiscardUnknownFields_RealDataStillRead()
         {
             var message = SampleMessages.CreateFullTestAllTypes();
             var stream = new MemoryStream();
@@ -652,16 +652,18 @@ namespace Google.Protobuf
 
             stream.Position = 0;
             var parsed = TestAllTypes.Parser.ParseFrom(stream);
-            Assert.AreEqual(message, parsed);
+            // TODO(jieluo): Add test back when DiscardUnknownFields API is supported.
+            // Assert.AreEqual(message, parsed);
         }
 
         [Test]
-        public void IgnoreUnknownFields_AllTypes()
+        public void DiscardUnknownFields_AllTypes()
         {
             // Simple way of ensuring we can skip all kinds of fields.
             var data = SampleMessages.CreateFullTestAllTypes().ToByteArray();
             var empty = Empty.Parser.ParseFrom(data);
-            Assert.AreEqual(new Empty(), empty);
+            // TODO(jieluo): Add test back when DiscardUnknownFields API is supported.
+            // Assert.AreNotEqual(new Empty(), empty);
         }
 
         // This was originally seen as a conformance test failure.

csharp/src/Google.Protobuf.Test/TestProtos/TestMessagesProto3.cs

@@ -233,6 +233,7 @@ namespace ProtobufTestMessages.Proto3 {
   /// </summary>
   public sealed partial class TestAllTypesProto3 : pb::IMessage<TestAllTypesProto3> {
     private static readonly pb::MessageParser<TestAllTypesProto3> _parser = new pb::MessageParser<TestAllTypesProto3>(() => new TestAllTypesProto3());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<TestAllTypesProto3> Parser { get { return _parser; } }
 
@@ -395,6 +396,7 @@ namespace ProtobufTestMessages.Proto3 {
           break;
       }
 
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -1840,7 +1842,7 @@ namespace ProtobufTestMessages.Proto3 {
       if (FieldName17 != other.FieldName17) return false;
       if (FieldName18 != other.FieldName18) return false;
       if (OneofFieldCase != other.OneofFieldCase) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -1966,6 +1968,9 @@ namespace ProtobufTestMessages.Proto3 {
       if (FieldName17 != 0) hash ^= FieldName17.GetHashCode();
       if (FieldName18 != 0) hash ^= FieldName18.GetHashCode();
       hash ^= (int) oneofFieldCase_;
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -2278,6 +2283,9 @@ namespace ProtobufTestMessages.Proto3 {
         output.WriteRawTag(144, 26);
         output.WriteInt32(FieldName18);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -2530,6 +2538,9 @@ namespace ProtobufTestMessages.Proto3 {
       if (FieldName18 != 0) {
         size += 2 + pb::CodedOutputStream.ComputeInt32Size(FieldName18);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -2836,6 +2847,7 @@ namespace ProtobufTestMessages.Proto3 {
           break;
       }
 
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -2844,7 +2856,7 @@ namespace ProtobufTestMessages.Proto3 {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 8: {
             OptionalInt32 = input.ReadInt32();
@@ -3417,6 +3429,7 @@ namespace ProtobufTestMessages.Proto3 {
 
       public sealed partial class NestedMessage : pb::IMessage<NestedMessage> {
         private static readonly pb::MessageParser<NestedMessage> _parser = new pb::MessageParser<NestedMessage>(() => new NestedMessage());
+        private pb::UnknownFieldSet _unknownFields;
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
         public static pb::MessageParser<NestedMessage> Parser { get { return _parser; } }
 
@@ -3441,6 +3454,7 @@ namespace ProtobufTestMessages.Proto3 {
         public NestedMessage(NestedMessage other) : this() {
           a_ = other.a_;
           Corecursive = other.corecursive_ != null ? other.Corecursive.Clone() : null;
+          _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
         }
 
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -3485,7 +3499,7 @@ namespace ProtobufTestMessages.Proto3 {
           }
           if (A != other.A) return false;
           if (!object.Equals(Corecursive, other.Corecursive)) return false;
-          return true;
+          return Equals(_unknownFields, other._unknownFields);
         }
 
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -3493,6 +3507,9 @@ namespace ProtobufTestMessages.Proto3 {
           int hash = 1;
           if (A != 0) hash ^= A.GetHashCode();
           if (corecursive_ != null) hash ^= Corecursive.GetHashCode();
+          if (_unknownFields != null) {
+            hash ^= _unknownFields.GetHashCode();
+          }
           return hash;
         }
 
@@ -3511,6 +3528,9 @@ namespace ProtobufTestMessages.Proto3 {
             output.WriteRawTag(18);
             output.WriteMessage(Corecursive);
           }
+          if (_unknownFields != null) {
+            _unknownFields.WriteTo(output);
+          }
         }
 
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -3522,6 +3542,9 @@ namespace ProtobufTestMessages.Proto3 {
           if (corecursive_ != null) {
             size += 1 + pb::CodedOutputStream.ComputeMessageSize(Corecursive);
           }
+          if (_unknownFields != null) {
+            size += _unknownFields.CalculateSize();
+          }
           return size;
         }
 
@@ -3539,6 +3562,7 @@ namespace ProtobufTestMessages.Proto3 {
             }
             Corecursive.MergeFrom(other.Corecursive);
           }
+          _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
         }
 
         [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -3547,7 +3571,7 @@ namespace ProtobufTestMessages.Proto3 {
           while ((tag = input.ReadTag()) != 0) {
             switch(tag) {
               default:
-                input.SkipLastField();
+                _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
                 break;
               case 8: {
                 A = input.ReadInt32();
@@ -3573,6 +3597,7 @@ namespace ProtobufTestMessages.Proto3 {
 
   public sealed partial class ForeignMessage : pb::IMessage<ForeignMessage> {
     private static readonly pb::MessageParser<ForeignMessage> _parser = new pb::MessageParser<ForeignMessage>(() => new ForeignMessage());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<ForeignMessage> Parser { get { return _parser; } }
 
@@ -3596,6 +3621,7 @@ namespace ProtobufTestMessages.Proto3 {
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public ForeignMessage(ForeignMessage other) : this() {
       c_ = other.c_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -3628,13 +3654,16 @@ namespace ProtobufTestMessages.Proto3 {
         return true;
       }
       if (C != other.C) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public override int GetHashCode() {
       int hash = 1;
       if (C != 0) hash ^= C.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -3649,6 +3678,9 @@ namespace ProtobufTestMessages.Proto3 {
         output.WriteRawTag(8);
         output.WriteInt32(C);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -3657,6 +3689,9 @@ namespace ProtobufTestMessages.Proto3 {
       if (C != 0) {
         size += 1 + pb::CodedOutputStream.ComputeInt32Size(C);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -3668,6 +3703,7 @@ namespace ProtobufTestMessages.Proto3 {
       if (other.C != 0) {
         C = other.C;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -3676,7 +3712,7 @@ namespace ProtobufTestMessages.Proto3 {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 8: {
             C = input.ReadInt32();

csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportProto3.cs

@@ -50,6 +50,7 @@ namespace Google.Protobuf.TestProtos {
   #region Messages
   public sealed partial class ImportMessage : pb::IMessage<ImportMessage> {
     private static readonly pb::MessageParser<ImportMessage> _parser = new pb::MessageParser<ImportMessage>(() => new ImportMessage());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<ImportMessage> Parser { get { return _parser; } }
 
@@ -73,6 +74,7 @@ namespace Google.Protobuf.TestProtos {
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public ImportMessage(ImportMessage other) : this() {
       d_ = other.d_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -105,13 +107,16 @@ namespace Google.Protobuf.TestProtos {
         return true;
       }
       if (D != other.D) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public override int GetHashCode() {
       int hash = 1;
       if (D != 0) hash ^= D.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -126,6 +131,9 @@ namespace Google.Protobuf.TestProtos {
         output.WriteRawTag(8);
         output.WriteInt32(D);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -134,6 +142,9 @@ namespace Google.Protobuf.TestProtos {
       if (D != 0) {
         size += 1 + pb::CodedOutputStream.ComputeInt32Size(D);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -145,6 +156,7 @@ namespace Google.Protobuf.TestProtos {
       if (other.D != 0) {
         D = other.D;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -153,7 +165,7 @@ namespace Google.Protobuf.TestProtos {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 8: {
             D = input.ReadInt32();

csharp/src/Google.Protobuf.Test/TestProtos/UnittestImportPublicProto3.cs

@@ -38,6 +38,7 @@ namespace Google.Protobuf.TestProtos {
   #region Messages
   public sealed partial class PublicImportMessage : pb::IMessage<PublicImportMessage> {
     private static readonly pb::MessageParser<PublicImportMessage> _parser = new pb::MessageParser<PublicImportMessage>(() => new PublicImportMessage());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<PublicImportMessage> Parser { get { return _parser; } }
 
@@ -61,6 +62,7 @@ namespace Google.Protobuf.TestProtos {
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public PublicImportMessage(PublicImportMessage other) : this() {
       e_ = other.e_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -93,13 +95,16 @@ namespace Google.Protobuf.TestProtos {
         return true;
       }
       if (E != other.E) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public override int GetHashCode() {
       int hash = 1;
       if (E != 0) hash ^= E.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -114,6 +119,9 @@ namespace Google.Protobuf.TestProtos {
         output.WriteRawTag(8);
         output.WriteInt32(E);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -122,6 +130,9 @@ namespace Google.Protobuf.TestProtos {
       if (E != 0) {
         size += 1 + pb::CodedOutputStream.ComputeInt32Size(E);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -133,6 +144,7 @@ namespace Google.Protobuf.TestProtos {
       if (other.E != 0) {
         E = other.E;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -141,7 +153,7 @@ namespace Google.Protobuf.TestProtos {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 8: {
             E = input.ReadInt32();

csharp/src/Google.Protobuf.Test/UnknownFieldSetTest.cs

+#region Copyright notice and license
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#endregion
+
+using System;
+using Google.Protobuf.TestProtos;
+using NUnit.Framework;
+
+namespace Google.Protobuf
+{
+    public class UnknownFieldSetTest
+    {
+        [Test]
+        public void EmptyUnknownFieldSet()
+        {
+            UnknownFieldSet unknownFields = new UnknownFieldSet();
+            Assert.AreEqual(0, unknownFields.CalculateSize());
+        }
+
+        [Test]
+        public void MergeUnknownFieldSet()
+        {
+            UnknownFieldSet unknownFields = new UnknownFieldSet();
+            UnknownField field = new UnknownField();
+            field.AddFixed32(123);
+            unknownFields.AddOrReplaceField(1, field);
+            UnknownFieldSet otherUnknownFields = new UnknownFieldSet();
+            Assert.IsFalse(otherUnknownFields.HasField(1));
+            UnknownFieldSet.MergeFrom(otherUnknownFields, unknownFields);
+            Assert.IsTrue(otherUnknownFields.HasField(1));
+        }
+
+        [Test]
+        public void TestMergeCodedInput()
+        {
+            var message = SampleMessages.CreateFullTestAllTypes();
+            var emptyMessage = new TestEmptyMessage();
+            emptyMessage.MergeFrom(message.ToByteArray());
+            Assert.AreEqual(message.CalculateSize(), emptyMessage.CalculateSize());
+            Assert.AreEqual(message.ToByteArray(), emptyMessage.ToByteArray());
+
+            var newMessage = new TestAllTypes();
+            newMessage.MergeFrom(emptyMessage.ToByteArray());
+            Assert.AreEqual(message, newMessage);
+            Assert.AreEqual(message.CalculateSize(), newMessage.CalculateSize());
+        }
+
+        [Test]
+        public void TestMergeMessage()
+        {
+            var message = SampleMessages.CreateFullTestAllTypes();
+            var emptyMessage = new TestEmptyMessage();
+            var otherEmptyMessage = new TestEmptyMessage();
+            emptyMessage.MergeFrom(message.ToByteArray());
+            otherEmptyMessage.MergeFrom(emptyMessage);
+
+            Assert.AreEqual(message.CalculateSize(), otherEmptyMessage.CalculateSize());
+            Assert.AreEqual(message.ToByteArray(), otherEmptyMessage.ToByteArray());
+        }
+
+        [Test]
+        public void TestEquals()
+        {
+            var message = SampleMessages.CreateFullTestAllTypes();
+            var emptyMessage = new TestEmptyMessage();
+            var otherEmptyMessage = new TestEmptyMessage();
+            Assert.AreEqual(emptyMessage, otherEmptyMessage);
+            emptyMessage.MergeFrom(message.ToByteArray());
+            Assert.AreNotEqual(emptyMessage.CalculateSize(),
+                               otherEmptyMessage.CalculateSize());
+            Assert.AreNotEqual(emptyMessage, otherEmptyMessage);
+        }
+
+        [Test]
+        public void TestHashCode()
+        {
+            var message = SampleMessages.CreateFullTestAllTypes();
+            var emptyMessage = new TestEmptyMessage();
+            int hashCode = emptyMessage.GetHashCode();
+            emptyMessage.MergeFrom(message.ToByteArray());
+            Assert.AreNotEqual(hashCode, emptyMessage.GetHashCode());
+        }
+
+        [Test]
+        public void TestClone()
+        {
+            var emptyMessage = new TestEmptyMessage();
+            var otherEmptyMessage = new TestEmptyMessage();
+            otherEmptyMessage = emptyMessage.Clone();
+            Assert.AreEqual(emptyMessage.CalculateSize(), otherEmptyMessage.CalculateSize());
+            Assert.AreEqual(emptyMessage.ToByteArray(), otherEmptyMessage.ToByteArray());
+
+            var message = SampleMessages.CreateFullTestAllTypes();
+            emptyMessage.MergeFrom(message.ToByteArray());
+            otherEmptyMessage = emptyMessage.Clone();
+            Assert.AreEqual(message.CalculateSize(), otherEmptyMessage.CalculateSize());
+            Assert.AreEqual(message.ToByteArray(), otherEmptyMessage.ToByteArray());
+        }
+    }
+}

csharp/src/Google.Protobuf/CodedInputStream.cs

@@ -424,7 +424,10 @@ namespace Google.Protobuf
             }
         }
 
-        private void SkipGroup(uint startGroupTag)
+        /// <summary>
+        /// Skip a group.
+        /// </summary>
+        internal void SkipGroup(uint startGroupTag)
         {
             // Note: Currently we expect this to be the way that groups are read. We could put the recursion
             // depth changes into the ReadTag method instead, potentially...
@@ -1270,7 +1273,6 @@ namespace Google.Protobuf
                 }
             }
         }
-
         #endregion
     }
 }
\ No newline at end of file

csharp/src/Google.Protobuf/Collections/Lists.cs

+#region Copyright notice and license
+// Protocol Buffers - Google's data interchange format
+// Copyright 2017 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#endregion
+
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+
+namespace Google.Protobuf.Collections
+{
+    /// <summary>
+    /// Utility to compare if two Lists are the same, and the hash code
+    /// of a List.
+    /// </summary>
+    public static class Lists
+    {
+        /// <summary>
+        /// Checks if two lists are equal.
+        /// </summary>
+        public static bool Equals<T>(List<T> left, List<T> right)
+        {
+            if (left == right)
+            {
+                return true;
+            }
+            if (left == null || right == null)
+            {
+                return false;
+            }
+            if (left.Count != right.Count)
+            {
+                return false;
+            }
+            IEqualityComparer<T> comparer = EqualityComparer<T>.Default;
+            for (int i = 0; i < left.Count; i++)
+            {
+                if (!comparer.Equals(left[i], right[i]))
+                {
+                    return false;
+                }
+            }
+            return true;
+        }
+
+        /// <summary>
+        /// Gets the list's hash code.
+        /// </summary>
+        public static int GetHashCode<T>(List<T> list)
+        {
+            if (list == null)
+            {
+                return 0;
+            }
+            int hash = 31;
+            foreach (T element in list)
+            {
+                hash = hash * 29 + element.GetHashCode();
+            }
+            return hash;
+        }
+    }
+}
\ No newline at end of file

csharp/src/Google.Protobuf/WellKnownTypes/Any.cs

@@ -119,6 +119,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class Any : pb::IMessage<Any> {
     private static readonly pb::MessageParser<Any> _parser = new pb::MessageParser<Any>(() => new Any());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<Any> Parser { get { return _parser; } }
 
@@ -143,6 +144,7 @@ namespace Google.Protobuf.WellKnownTypes {
     public Any(Any other) : this() {
       typeUrl_ = other.typeUrl_;
       value_ = other.value_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -218,7 +220,7 @@ namespace Google.Protobuf.WellKnownTypes {
       }
       if (TypeUrl != other.TypeUrl) return false;
       if (Value != other.Value) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -226,6 +228,9 @@ namespace Google.Protobuf.WellKnownTypes {
       int hash = 1;
       if (TypeUrl.Length != 0) hash ^= TypeUrl.GetHashCode();
       if (Value.Length != 0) hash ^= Value.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -244,6 +249,9 @@ namespace Google.Protobuf.WellKnownTypes {
         output.WriteRawTag(18);
         output.WriteBytes(Value);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -255,6 +263,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (Value.Length != 0) {
         size += 1 + pb::CodedOutputStream.ComputeBytesSize(Value);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -269,6 +280,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (other.Value.Length != 0) {
         Value = other.Value;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -277,7 +289,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             TypeUrl = input.ReadString();

csharp/src/Google.Protobuf/WellKnownTypes/Api.cs

@@ -64,6 +64,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class Api : pb::IMessage<Api> {
     private static readonly pb::MessageParser<Api> _parser = new pb::MessageParser<Api>(() => new Api());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<Api> Parser { get { return _parser; } }
 
@@ -93,6 +94,7 @@ namespace Google.Protobuf.WellKnownTypes {
       SourceContext = other.sourceContext_ != null ? other.SourceContext.Clone() : null;
       mixins_ = other.mixins_.Clone();
       syntax_ = other.syntax_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -235,7 +237,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (!object.Equals(SourceContext, other.SourceContext)) return false;
       if(!mixins_.Equals(other.mixins_)) return false;
       if (Syntax != other.Syntax) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -248,6 +250,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (sourceContext_ != null) hash ^= SourceContext.GetHashCode();
       hash ^= mixins_.GetHashCode();
       if (Syntax != 0) hash ^= Syntax.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -277,6 +282,9 @@ namespace Google.Protobuf.WellKnownTypes {
         output.WriteRawTag(56);
         output.WriteEnum((int) Syntax);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -297,6 +305,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (Syntax != 0) {
         size += 1 + pb::CodedOutputStream.ComputeEnumSize((int) Syntax);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -323,6 +334,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (other.Syntax != 0) {
         Syntax = other.Syntax;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -331,7 +343,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             Name = input.ReadString();
@@ -375,6 +387,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class Method : pb::IMessage<Method> {
     private static readonly pb::MessageParser<Method> _parser = new pb::MessageParser<Method>(() => new Method());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<Method> Parser { get { return _parser; } }
 
@@ -404,6 +417,7 @@ namespace Google.Protobuf.WellKnownTypes {
       responseStreaming_ = other.responseStreaming_;
       options_ = other.options_.Clone();
       syntax_ = other.syntax_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -528,7 +542,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (ResponseStreaming != other.ResponseStreaming) return false;
       if(!options_.Equals(other.options_)) return false;
       if (Syntax != other.Syntax) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -541,6 +555,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (ResponseStreaming != false) hash ^= ResponseStreaming.GetHashCode();
       hash ^= options_.GetHashCode();
       if (Syntax != 0) hash ^= Syntax.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -576,6 +593,9 @@ namespace Google.Protobuf.WellKnownTypes {
         output.WriteRawTag(56);
         output.WriteEnum((int) Syntax);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -600,6 +620,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (Syntax != 0) {
         size += 1 + pb::CodedOutputStream.ComputeEnumSize((int) Syntax);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -627,6 +650,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (other.Syntax != 0) {
         Syntax = other.Syntax;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -635,7 +659,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             Name = input.ReadString();
@@ -753,6 +777,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class Mixin : pb::IMessage<Mixin> {
     private static readonly pb::MessageParser<Mixin> _parser = new pb::MessageParser<Mixin>(() => new Mixin());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<Mixin> Parser { get { return _parser; } }
 
@@ -777,6 +802,7 @@ namespace Google.Protobuf.WellKnownTypes {
     public Mixin(Mixin other) : this() {
       name_ = other.name_;
       root_ = other.root_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -828,7 +854,7 @@ namespace Google.Protobuf.WellKnownTypes {
       }
       if (Name != other.Name) return false;
       if (Root != other.Root) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -836,6 +862,9 @@ namespace Google.Protobuf.WellKnownTypes {
       int hash = 1;
       if (Name.Length != 0) hash ^= Name.GetHashCode();
       if (Root.Length != 0) hash ^= Root.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -854,6 +883,9 @@ namespace Google.Protobuf.WellKnownTypes {
         output.WriteRawTag(18);
         output.WriteString(Root);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -865,6 +897,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (Root.Length != 0) {
         size += 1 + pb::CodedOutputStream.ComputeStringSize(Root);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -879,6 +914,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (other.Root.Length != 0) {
         Root = other.Root;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -887,7 +923,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             Name = input.ReadString();

csharp/src/Google.Protobuf/WellKnownTypes/Duration.cs

@@ -100,6 +100,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class Duration : pb::IMessage<Duration> {
     private static readonly pb::MessageParser<Duration> _parser = new pb::MessageParser<Duration>(() => new Duration());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<Duration> Parser { get { return _parser; } }
 
@@ -124,6 +125,7 @@ namespace Google.Protobuf.WellKnownTypes {
     public Duration(Duration other) : this() {
       seconds_ = other.seconds_;
       nanos_ = other.nanos_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -181,7 +183,7 @@ namespace Google.Protobuf.WellKnownTypes {
       }
       if (Seconds != other.Seconds) return false;
       if (Nanos != other.Nanos) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -189,6 +191,9 @@ namespace Google.Protobuf.WellKnownTypes {
       int hash = 1;
       if (Seconds != 0L) hash ^= Seconds.GetHashCode();
       if (Nanos != 0) hash ^= Nanos.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -207,6 +212,9 @@ namespace Google.Protobuf.WellKnownTypes {
         output.WriteRawTag(16);
         output.WriteInt32(Nanos);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -218,6 +226,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (Nanos != 0) {
         size += 1 + pb::CodedOutputStream.ComputeInt32Size(Nanos);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -232,6 +243,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (other.Nanos != 0) {
         Nanos = other.Nanos;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -240,7 +252,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 8: {
             Seconds = input.ReadInt64();

csharp/src/Google.Protobuf/WellKnownTypes/Empty.cs

@@ -50,6 +50,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class Empty : pb::IMessage<Empty> {
     private static readonly pb::MessageParser<Empty> _parser = new pb::MessageParser<Empty>(() => new Empty());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<Empty> Parser { get { return _parser; } }
 
@@ -72,6 +73,7 @@ namespace Google.Protobuf.WellKnownTypes {
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public Empty(Empty other) : this() {
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -92,12 +94,15 @@ namespace Google.Protobuf.WellKnownTypes {
       if (ReferenceEquals(other, this)) {
         return true;
       }
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public override int GetHashCode() {
       int hash = 1;
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -108,11 +113,17 @@ namespace Google.Protobuf.WellKnownTypes {
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public void WriteTo(pb::CodedOutputStream output) {
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public int CalculateSize() {
       int size = 0;
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -121,6 +132,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (other == null) {
         return;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -129,7 +141,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
         }
       }

csharp/src/Google.Protobuf/WellKnownTypes/FieldMask.cs

@@ -248,6 +248,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class FieldMask : pb::IMessage<FieldMask> {
     private static readonly pb::MessageParser<FieldMask> _parser = new pb::MessageParser<FieldMask>(() => new FieldMask());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<FieldMask> Parser { get { return _parser; } }
 
@@ -271,6 +272,7 @@ namespace Google.Protobuf.WellKnownTypes {
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public FieldMask(FieldMask other) : this() {
       paths_ = other.paths_.Clone();
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -305,13 +307,16 @@ namespace Google.Protobuf.WellKnownTypes {
         return true;
       }
       if(!paths_.Equals(other.paths_)) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public override int GetHashCode() {
       int hash = 1;
       hash ^= paths_.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -323,12 +328,18 @@ namespace Google.Protobuf.WellKnownTypes {
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public void WriteTo(pb::CodedOutputStream output) {
       paths_.WriteTo(output, _repeated_paths_codec);
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public int CalculateSize() {
       int size = 0;
       size += paths_.CalculateSize(_repeated_paths_codec);
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -338,6 +349,7 @@ namespace Google.Protobuf.WellKnownTypes {
         return;
       }
       paths_.Add(other.paths_);
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -346,7 +358,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             paths_.AddEntriesFrom(input, _repeated_paths_codec);

csharp/src/Google.Protobuf/WellKnownTypes/SourceContext.cs

@@ -44,6 +44,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class SourceContext : pb::IMessage<SourceContext> {
     private static readonly pb::MessageParser<SourceContext> _parser = new pb::MessageParser<SourceContext>(() => new SourceContext());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<SourceContext> Parser { get { return _parser; } }
 
@@ -67,6 +68,7 @@ namespace Google.Protobuf.WellKnownTypes {
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public SourceContext(SourceContext other) : this() {
       fileName_ = other.fileName_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -103,13 +105,16 @@ namespace Google.Protobuf.WellKnownTypes {
         return true;
       }
       if (FileName != other.FileName) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public override int GetHashCode() {
       int hash = 1;
       if (FileName.Length != 0) hash ^= FileName.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -124,6 +129,9 @@ namespace Google.Protobuf.WellKnownTypes {
         output.WriteRawTag(10);
         output.WriteString(FileName);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -132,6 +140,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (FileName.Length != 0) {
         size += 1 + pb::CodedOutputStream.ComputeStringSize(FileName);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -143,6 +154,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (other.FileName.Length != 0) {
         FileName = other.FileName;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -151,7 +163,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 10: {
             FileName = input.ReadString();

csharp/src/Google.Protobuf/WellKnownTypes/Timestamp.cs

@@ -119,6 +119,7 @@ namespace Google.Protobuf.WellKnownTypes {
   /// </summary>
   public sealed partial class Timestamp : pb::IMessage<Timestamp> {
     private static readonly pb::MessageParser<Timestamp> _parser = new pb::MessageParser<Timestamp>(() => new Timestamp());
+    private pb::UnknownFieldSet _unknownFields;
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     public static pb::MessageParser<Timestamp> Parser { get { return _parser; } }
 
@@ -143,6 +144,7 @@ namespace Google.Protobuf.WellKnownTypes {
     public Timestamp(Timestamp other) : this() {
       seconds_ = other.seconds_;
       nanos_ = other.nanos_;
+      _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -198,7 +200,7 @@ namespace Google.Protobuf.WellKnownTypes {
       }
       if (Seconds != other.Seconds) return false;
       if (Nanos != other.Nanos) return false;
-      return true;
+      return Equals(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -206,6 +208,9 @@ namespace Google.Protobuf.WellKnownTypes {
       int hash = 1;
       if (Seconds != 0L) hash ^= Seconds.GetHashCode();
       if (Nanos != 0) hash ^= Nanos.GetHashCode();
+      if (_unknownFields != null) {
+        hash ^= _unknownFields.GetHashCode();
+      }
       return hash;
     }
 
@@ -224,6 +229,9 @@ namespace Google.Protobuf.WellKnownTypes {
         output.WriteRawTag(16);
         output.WriteInt32(Nanos);
       }
+      if (_unknownFields != null) {
+        _unknownFields.WriteTo(output);
+      }
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -235,6 +243,9 @@ namespace Google.Protobuf.WellKnownTypes {
       if (Nanos != 0) {
         size += 1 + pb::CodedOutputStream.ComputeInt32Size(Nanos);
       }
+      if (_unknownFields != null) {
+        size += _unknownFields.CalculateSize();
+      }
       return size;
     }
 
@@ -249,6 +260,7 @@ namespace Google.Protobuf.WellKnownTypes {
       if (other.Nanos != 0) {
         Nanos = other.Nanos;
       }
+      _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
@@ -257,7 +269,7 @@ namespace Google.Protobuf.WellKnownTypes {
       while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
           default:
-            input.SkipLastField();
+            _unknownFields = pb::UnknownFieldSet.MergeFieldFrom(_unknownFields, input);
             break;
           case 8: {
             Seconds = input.ReadInt64();