Merge pull request #404 from anandolee/master

Add oneof support for c#

10 files changed, 463 insertions, 53 deletions

diff --git a/src/google/protobuf/compiler/csharp/csharp_enum_field.cc b/src/google/protobuf/compiler/csharp/csharp_enum_field.cc
index 34d1c5c6..a2d8a98b 100644
--- a/src/google/protobuf/compiler/csharp/csharp_enum_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_enum_field.cc
@@ -49,6 +49,11 @@ namespace csharp {
 EnumFieldGenerator::EnumFieldGenerator(const FieldDescriptor* descriptor,
                                        int fieldOrdinal)
     : FieldGeneratorBase(descriptor, fieldOrdinal) {
+  if (SupportFieldPresence(descriptor_->file())) {
+    has_property_check = "has" + property_name();
+  } else {
+    has_property_check = property_name() + " != " + default_value();
+  }
 }
 
 EnumFieldGenerator::~EnumFieldGenerator() {
@@ -122,8 +127,7 @@ void EnumFieldGenerator::GenerateBuildingCode(Writer* writer) {
 
 void EnumFieldGenerator::GenerateParsingCode(Writer* writer) {
   writer->WriteLine("object unknown;");
-  writer->WriteLine("if(input.ReadEnum(ref result.$0$_, out unknown)) {",
-                    name());
+  writer->WriteLine("if(input.ReadEnum(ref result.$0$_, out unknown)) {", name());
   if (SupportFieldPresence(descriptor_->file())) {
     writer->WriteLine("  result.has$0$ = true;", property_name());
   }
@@ -141,11 +145,7 @@ void EnumFieldGenerator::GenerateParsingCode(Writer* writer) {
 }
 
 void EnumFieldGenerator::GenerateSerializationCode(Writer* writer) {
-  if (SupportFieldPresence(descriptor_->file())) {
-    writer->WriteLine("if (has$0$) {", property_name());
-  } else {
-    writer->WriteLine("if ($0$ != $1$) {", property_name(), default_value());
-  }
+  writer->WriteLine("if ($0$) {", has_property_check);
   writer->WriteLine(
       "  output.WriteEnum($0$, field_names[$2$], (int) $1$, $1$);", number(),
       property_name(), field_ordinal());
@@ -153,11 +153,7 @@ void EnumFieldGenerator::GenerateSerializationCode(Writer* writer) {
 }
 
 void EnumFieldGenerator::GenerateSerializedSizeCode(Writer* writer) {
-  if (SupportFieldPresence(descriptor_->file())) {
-    writer->WriteLine("if (has$0$) {", property_name());
-  } else {
-    writer->WriteLine("if ($0$ != $1$) {", property_name(), default_value());
-  }
+  writer->WriteLine("if ($0$) {", has_property_check);
   writer->WriteLine(
       "  size += pb::CodedOutputStream.ComputeEnumSize($0$, (int) $1$);",
       number(), property_name());
@@ -165,11 +161,7 @@ void EnumFieldGenerator::GenerateSerializedSizeCode(Writer* writer) {
 }
 
 void EnumFieldGenerator::WriteHash(Writer* writer) {
-  if (SupportFieldPresence(descriptor_->file())) {
-    writer->WriteLine("if (has$0$) {", property_name());
-  } else {
-    writer->WriteLine("if ($0$ != $1$) {", property_name(), default_value());
-  }
+  writer->WriteLine("if ($0$) {", has_property_check);
   writer->WriteLine("  hash ^= $0$_.GetHashCode();", name());
   writer->WriteLine("}");
 }
@@ -184,13 +176,94 @@ void EnumFieldGenerator::WriteEquals(Writer* writer) {
   }
 }
 void EnumFieldGenerator::WriteToString(Writer* writer) {
+  writer->WriteLine("PrintField(\"$0$\", $1$, $2$_, writer);",
+                    descriptor_->name(), has_property_check, name());
+}
+
+EnumOneofFieldGenerator::EnumOneofFieldGenerator(const FieldDescriptor* descriptor,
+						 int fieldOrdinal)
+  : EnumFieldGenerator(descriptor, fieldOrdinal) {
+  has_property_check = oneof_name() + "Case_ == " + oneof_property_name() +
+    "OneofCase." + property_name();
+}
+
+EnumOneofFieldGenerator::~EnumOneofFieldGenerator() {
+}
+
+void EnumOneofFieldGenerator::GenerateMembers(Writer* writer) {
+  AddDeprecatedFlag(writer);
   if (SupportFieldPresence(descriptor_->file())) {
-    writer->WriteLine("PrintField(\"$0$\", has$1$, $2$_, writer);",
-                      descriptor_->name(), property_name(), name());
-  } else {
-    writer->WriteLine("PrintField(\"$0$\", $1$_, writer);",
-                      descriptor_->name(), name());
+    writer->WriteLine("public bool Has$0$ {", property_name());
+    writer->WriteLine("  get { return $0$; }", has_property_check);
+    writer->WriteLine("}");
+  }
+  AddPublicMemberAttributes(writer);
+  writer->WriteLine("public $0$ $1$ {", type_name(), property_name());
+  writer->WriteLine("  get { return $0$ ? ($1$) $2$_ : $3$; }",
+		    has_property_check, type_name(), oneof_name(), default_value());
+  writer->WriteLine("}");
+}
+
+void EnumOneofFieldGenerator::GenerateBuilderMembers(Writer* writer) {
+  AddDeprecatedFlag(writer);
+  if (SupportFieldPresence(descriptor_->file())) {
+    writer->WriteLine("public bool Has$0$ {", property_name());
+    writer->WriteLine(" get { return result.$0$; }", has_property_check);
+    writer->WriteLine("}");
   }
+  AddPublicMemberAttributes(writer);
+  writer->WriteLine("public $0$ $1$ {", type_name(), property_name());
+  writer->WriteLine("  get { return result.$0$ ? ($1$) result.$2$_ : $3$; }",
+		    has_property_check, type_name(), oneof_name(), default_value());
+  writer->WriteLine("  set { Set$0$(value); }", property_name());
+  writer->WriteLine("}");
+  AddPublicMemberAttributes(writer);
+  writer->WriteLine("public Builder Set$0$($1$ value) {", property_name(),
+                    type_name());
+  writer->WriteLine("  PrepareBuilder();");
+  writer->WriteLine("  result.$0$_ = value;", oneof_name());
+  writer->WriteLine("  result.$0$Case_ = $1$OneofCase.$2$;",
+                    oneof_name(), oneof_property_name(), property_name());
+  writer->WriteLine("  return this;");
+  writer->WriteLine("}");
+  AddDeprecatedFlag(writer);
+  writer->WriteLine("public Builder Clear$0$() {", property_name());
+  writer->WriteLine("  PrepareBuilder();");
+  writer->WriteLine("  if (result.$0$) {", has_property_check);
+  writer->WriteLine("    result.$0$Case_ = $1$OneofCase.None;",
+                    oneof_name(), oneof_property_name());
+  writer->WriteLine("  }");
+  writer->WriteLine("  return this;");
+  writer->WriteLine("}");
+}
+
+void EnumOneofFieldGenerator::WriteEquals(Writer* writer) {
+  writer->WriteLine("if (!$0$.Equals(other.$0$)) return false;", property_name());
+}
+void EnumOneofFieldGenerator::WriteToString(Writer* writer) {
+  writer->WriteLine("PrintField(\"$0$\", $1$, $2$_, writer);",
+                    descriptor_->name(), has_property_check, oneof_name());
+}
+
+void EnumOneofFieldGenerator::GenerateParsingCode(Writer* writer) {
+  writer->WriteLine("object unknown;");
+  writer->WriteLine("$0$ enumValue = $1$;", type_name(), default_value());
+  writer->WriteLine("if(input.ReadEnum(ref enumValue, out unknown)) {",
+                    name());
+  writer->WriteLine("  result.$0$_ = enumValue;", oneof_name());
+  writer->WriteLine("  result.$0$Case_ = $1$OneofCase.$2$;",
+		    oneof_name(), oneof_property_name(), property_name());
+  writer->WriteLine("} else if(unknown is int) {");
+  if (!use_lite_runtime()) {
+    writer->WriteLine("  if (unknownFields == null) {");  // First unknown field - create builder now
+    writer->WriteLine(
+        "    unknownFields = pb::UnknownFieldSet.CreateBuilder(this.UnknownFields);");
+    writer->WriteLine("  }");
+    writer->WriteLine(
+        "  unknownFields.MergeVarintField($0$, (ulong)(int)unknown);",
+        number());
+  }
+  writer->WriteLine("}");
 }
 
 }  // namespace csharp
diff --git a/src/google/protobuf/compiler/csharp/csharp_enum_field.h b/src/google/protobuf/compiler/csharp/csharp_enum_field.h
index b21fa9dc..565287b2 100644
--- a/src/google/protobuf/compiler/csharp/csharp_enum_field.h
+++ b/src/google/protobuf/compiler/csharp/csharp_enum_field.h
@@ -60,10 +60,28 @@ class EnumFieldGenerator : public FieldGeneratorBase {
   virtual void WriteEquals(Writer* writer);
   virtual void WriteToString(Writer* writer);
 
+ protected:
+  string has_property_check;
+
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(EnumFieldGenerator);
 };
 
+class EnumOneofFieldGenerator : public EnumFieldGenerator {
+ public:
+  EnumOneofFieldGenerator(const FieldDescriptor* descriptor, int fieldOrdinal);
+  ~EnumOneofFieldGenerator();
+
+  virtual void GenerateMembers(Writer* writer);
+  virtual void GenerateBuilderMembers(Writer* writer);
+  virtual void WriteEquals(Writer* writer);
+  virtual void WriteToString(Writer* writer);
+  virtual void GenerateParsingCode(Writer* writer);
+
+ private:
+  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(EnumOneofFieldGenerator);
+};
+
 }  // namespace csharp
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/csharp/csharp_field_base.cc b/src/google/protobuf/compiler/csharp/csharp_field_base.cc
index 145b6743..dfc803e6 100644
--- a/src/google/protobuf/compiler/csharp/csharp_field_base.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_field_base.cc
@@ -81,6 +81,14 @@ void FieldGeneratorBase::AddPublicMemberAttributes(Writer* writer) {
   AddDeprecatedFlag(writer);
 }
 
+std::string FieldGeneratorBase::oneof_property_name() {
+  return UnderscoresToCamelCase(descriptor_->containing_oneof()->name(), true);
+}
+
+std::string FieldGeneratorBase::oneof_name() {
+  return UnderscoresToCamelCase(descriptor_->containing_oneof()->name(), false);
+}
+
 std::string FieldGeneratorBase::property_name() {
   return GetPropertyName(descriptor_);
 }
diff --git a/src/google/protobuf/compiler/csharp/csharp_field_base.h b/src/google/protobuf/compiler/csharp/csharp_field_base.h
index 311f7a6e..312da12b 100644
--- a/src/google/protobuf/compiler/csharp/csharp_field_base.h
+++ b/src/google/protobuf/compiler/csharp/csharp_field_base.h
@@ -71,6 +71,8 @@ class FieldGeneratorBase : public SourceGeneratorBase {
 
   void AddPublicMemberAttributes(Writer* writer);
 
+  std::string oneof_property_name();
+  std::string oneof_name();
   std::string property_name();
   std::string name();
   std::string type_name();
diff --git a/src/google/protobuf/compiler/csharp/csharp_helpers.cc b/src/google/protobuf/compiler/csharp/csharp_helpers.cc
index 4580b7be..76e2c850 100644
--- a/src/google/protobuf/compiler/csharp/csharp_helpers.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_helpers.cc
@@ -346,19 +346,31 @@ FieldGeneratorBase* CreateFieldGenerator(const FieldDescriptor* descriptor,
       if (descriptor->is_repeated()) {
         return new RepeatedMessageFieldGenerator(descriptor, fieldOrdinal);
       } else {
-        return new MessageFieldGenerator(descriptor, fieldOrdinal);
+	if (descriptor->containing_oneof()) {
+	  return new MessageOneofFieldGenerator(descriptor, fieldOrdinal);
+	} else {
+	  return new MessageFieldGenerator(descriptor, fieldOrdinal);
+	}
       }
     case FieldDescriptor::TYPE_ENUM:
       if (descriptor->is_repeated()) {
         return new RepeatedEnumFieldGenerator(descriptor, fieldOrdinal);
       } else {
-        return new EnumFieldGenerator(descriptor, fieldOrdinal);
+	if (descriptor->containing_oneof()) {
+	  return new EnumOneofFieldGenerator(descriptor, fieldOrdinal);
+	} else {
+	  return new EnumFieldGenerator(descriptor, fieldOrdinal);
+	}
       }
     default:
       if (descriptor->is_repeated()) {
         return new RepeatedPrimitiveFieldGenerator(descriptor, fieldOrdinal);
       } else {
-        return new PrimitiveFieldGenerator(descriptor, fieldOrdinal);
+	if (descriptor->containing_oneof()) {
+	  return new PrimitiveOneofFieldGenerator(descriptor, fieldOrdinal);
+	} else {
+	  return new PrimitiveFieldGenerator(descriptor, fieldOrdinal);
+	}
       }
   }
 }
diff --git a/src/google/protobuf/compiler/csharp/csharp_message.cc b/src/google/protobuf/compiler/csharp/csharp_message.cc
index 96f7c17c..22681235 100644
--- a/src/google/protobuf/compiler/csharp/csharp_message.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_message.cc
@@ -156,6 +156,10 @@ void MessageGenerator::GenerateStaticVariableInitializers(Writer* writer) {
     for (int i = 0; i < descriptor_->field_count(); i++) {
       writer->Write("\"$0$\", ", GetPropertyName(descriptor_->field(i)));
     }
+    for (int i = 0; i < descriptor_->oneof_decl_count(); i++) {
+      writer->Write("\"$0$\", ",
+		    UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), true));
+    }
     writer->WriteLine("});");
   }
 
@@ -260,6 +264,31 @@ void MessageGenerator::Generate(Writer* writer) {
     writer->WriteLine();
   }
 
+  // oneof
+  for (int i = 0; i < descriptor_->oneof_decl_count(); i++) {
+    string name = UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), false);
+    string property_name = UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), true);
+    writer->WriteLine("private object $0$_;", name);
+    writer->WriteLine("public enum $0$OneofCase {", property_name);
+    writer->Indent();
+    for (int j = 0; j < descriptor_->oneof_decl(i)->field_count(); j++) {
+      const FieldDescriptor* field = descriptor_->oneof_decl(i)->field(j);
+      writer->WriteLine("$0$ = $1$,",
+			GetPropertyName(field),
+			SimpleItoa(field->number()));
+    }
+    writer->WriteLine("None = 0,");
+    writer->Outdent();
+    writer->WriteLine("}");
+    writer->WriteLine("private $0$OneofCase $1$Case_ = $0$OneofCase.None;",
+		      property_name, name);
+    writer->WriteLine("public $0$OneofCase $0$Case {", property_name);
+    writer->WriteLine("  get { return $0$Case_; }", name);
+    writer->WriteLine("}");
+    writer->WriteLine();
+  }
+
+  // Fields
   for (int i = 0; i < descriptor_->field_count(); i++) {
     const FieldDescriptor* fieldDescriptor = descriptor_->field(i);
 
@@ -310,9 +339,19 @@ void MessageGenerator::GenerateLiteRuntimeMethods(Writer* writer) {
   writer->Indent();
   writer->WriteLine("int hash = GetType().GetHashCode();");
   for (int i = 0; i < descriptor_->field_count(); i++) {
-    scoped_ptr<FieldGeneratorBase> generator(
-        CreateFieldGeneratorInternal(descriptor_->field(i)));
-    generator->WriteHash(writer);
+    const FieldDescriptor* field = descriptor_->field(i);
+    if (field->containing_oneof() == NULL) {
+      scoped_ptr<FieldGeneratorBase> generator(
+          CreateFieldGeneratorInternal(field));
+      generator->WriteHash(writer);
+    }
+  }
+  for (int i = 0; i < descriptor_->oneof_decl_count(); i++) {
+    string name = UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), false);
+    string property_name = UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), true);
+    writer->WriteLine("if ($0$Case_ != $1$OneofCase.None) {", name, property_name);
+    writer->WriteLine("  hash ^= $0$_.GetHashCode();", name);
+    writer->WriteLine("}");
   }
   if (callbase) {
     writer->WriteLine("hash ^= base.GetHashCode();");
@@ -577,6 +616,23 @@ void MessageGenerator::GenerateBuilder(Writer* writer) {
     // No field comment :(
     generator->GenerateBuilderMembers(writer);
   }
+
+  // oneof
+  for (int i = 0; i < descriptor_->oneof_decl_count(); i++) {
+    writer->WriteLine();
+    string name = UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), false);
+    string property_name = UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), true);
+    writer->WriteLine("public $0$OneofCase $0$Case {", property_name);
+    writer->WriteLine("  get { return result.$0$Case_; }", name);
+    writer->WriteLine("}");
+    writer->WriteLine("public Builder Clear$0$() {", property_name);
+    writer->WriteLine("  PrepareBuilder();");
+    writer->WriteLine("  result.$0$_ = null;", name);
+    writer->WriteLine("  result.$0$Case_ = $1$OneofCase.None;", name, property_name);
+    writer->WriteLine("  return this;");
+    writer->WriteLine("}");
+  }
+
   writer->Outdent();
   writer->WriteLine("}");
 }
@@ -675,10 +731,37 @@ void MessageGenerator::GenerateCommonBuilderMethods(Writer* writer) {
                       full_class_name());
     writer->WriteLine("PrepareBuilder();");
     for (int i = 0; i < descriptor_->field_count(); i++) {
-      scoped_ptr<FieldGeneratorBase> generator(
-          CreateFieldGeneratorInternal(descriptor_->field(i)));
-      generator->GenerateMergingCode(writer);
+      if (!descriptor_->field(i)->containing_oneof()) {
+	scoped_ptr<FieldGeneratorBase> generator(
+	  CreateFieldGeneratorInternal(descriptor_->field(i)));
+	generator->GenerateMergingCode(writer);
+      }
+     }
+
+    // Merge oneof fields
+    for (int i = 0; i < descriptor_->oneof_decl_count(); ++i) {
+      string name = UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), false);
+      string property_name = UnderscoresToCamelCase(descriptor_->oneof_decl(i)->name(), true);
+      writer->WriteLine("switch (other.$0$Case) {", property_name);
+      writer->Indent();
+      for (int j = 0; j < descriptor_->oneof_decl(i)->field_count(); j++) {
+        const FieldDescriptor* field = descriptor_->oneof_decl(i)->field(j);
+	writer->WriteLine("case $0$OneofCase.$1$: {",
+          property_name, GetPropertyName(field));
+	if (field->type() == FieldDescriptor::TYPE_GROUP ||
+	    field->type() == FieldDescriptor::TYPE_MESSAGE) {
+	  writer->WriteLine("  Merge$0$(other.$0$);", GetPropertyName(field));
+	} else {
+	  writer->WriteLine("  Set$0$(other.$0$);", GetPropertyName(field));
+	}
+        writer->WriteLine("  break;");
+	writer->WriteLine("}");
+      }
+      writer->WriteLine("case $0$OneofCase.None: { break; }", property_name);
+      writer->Outdent();
+      writer->WriteLine("}");
     }
+
     // if message type has extensions
     if (descriptor_->extension_range_count() > 0) {
       writer->WriteLine("  this.MergeExtensionFields(other);");
diff --git a/src/google/protobuf/compiler/csharp/csharp_message_field.cc b/src/google/protobuf/compiler/csharp/csharp_message_field.cc
index 10464c4b..b533d735 100644
--- a/src/google/protobuf/compiler/csharp/csharp_message_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_message_field.cc
@@ -50,6 +50,7 @@ namespace csharp {
 MessageFieldGenerator::MessageFieldGenerator(const FieldDescriptor* descriptor,
                                              int fieldOrdinal)
     : FieldGeneratorBase(descriptor, fieldOrdinal) {
+  has_property_check = "has" + property_name();
 }
 
 MessageFieldGenerator::~MessageFieldGenerator() {
@@ -149,7 +150,7 @@ void MessageFieldGenerator::GenerateParsingCode(Writer* writer) {
 }
 
 void MessageFieldGenerator::GenerateSerializationCode(Writer* writer) {
-  writer->WriteLine("if (has$0$) {", property_name());
+  writer->WriteLine("if ($0$) {", has_property_check);
   writer->WriteLine("  output.Write$0$($1$, field_names[$3$], $2$);",
                     message_or_group(), number(), property_name(),
                     field_ordinal());
@@ -157,7 +158,7 @@ void MessageFieldGenerator::GenerateSerializationCode(Writer* writer) {
 }
 
 void MessageFieldGenerator::GenerateSerializedSizeCode(Writer* writer) {
-  writer->WriteLine("if (has$0$) {", property_name());
+  writer->WriteLine("if ($0$) {", has_property_check);
   writer->WriteLine("  size += pb::CodedOutputStream.Compute$0$Size($1$, $2$);",
                     message_or_group(), number(), property_name());
   writer->WriteLine("}");
@@ -177,6 +178,119 @@ void MessageFieldGenerator::WriteToString(Writer* writer) {
                     property_name(), name(), GetFieldName(descriptor_));
 }
 
+MessageOneofFieldGenerator::MessageOneofFieldGenerator(const FieldDescriptor* descriptor,
+						       int fieldOrdinal)
+    : MessageFieldGenerator(descriptor, fieldOrdinal) {
+  has_property_check = oneof_name() + "Case_ == " + oneof_property_name() +
+    "OneofCase." + property_name();
+}
+
+MessageOneofFieldGenerator::~MessageOneofFieldGenerator() {
+
+}
+
+void MessageOneofFieldGenerator::GenerateMembers(Writer* writer) {
+  if (SupportFieldPresence(descriptor_->file())) {
+    AddDeprecatedFlag(writer);
+    writer->WriteLine("public bool Has$0$ {", property_name());
+    writer->WriteLine("  get { return $0$; }", has_property_check);
+    writer->WriteLine("}");
+  }
+  AddDeprecatedFlag(writer);
+  writer->WriteLine("public $0$ $1$ {", type_name(), property_name());
+  writer->WriteLine("  get { return $0$ ? ($1$) $2$_ : $3$; }",
+		    has_property_check, type_name(), oneof_name(), default_value());
+  writer->WriteLine("}");
+}
+
+void MessageOneofFieldGenerator::GenerateBuilderMembers(Writer* writer) {
+  if (SupportFieldPresence(descriptor_->file())) {
+    AddDeprecatedFlag(writer);
+    writer->WriteLine("public bool Has$0$ {", property_name());
+    writer->WriteLine(" get { return result.$0$; }", has_property_check);
+    writer->WriteLine("}");
+  }
+  AddDeprecatedFlag(writer);
+  writer->WriteLine("public $0$ $1$ {", type_name(), property_name());
+  writer->WriteLine("  get { return result.$0$ ? ($1$) result.$2$_ : $3$; }",
+		    has_property_check, type_name(), oneof_name(), default_value());
+  writer->WriteLine("  set { Set$0$(value); }", property_name());
+  writer->WriteLine("}");
+  AddDeprecatedFlag(writer);
+  writer->WriteLine("public Builder Set$0$($1$ value) {", property_name(),
+                    type_name());
+  AddNullCheck(writer);
+  writer->WriteLine("  PrepareBuilder();");
+  writer->WriteLine("  result.$0$Case_ = $1$OneofCase.$2$;",
+		    oneof_name(), oneof_property_name(), property_name());
+  writer->WriteLine("  result.$0$_ = value;", oneof_name());
+  writer->WriteLine("  return this;");
+  writer->WriteLine("}");
+  AddDeprecatedFlag(writer);
+  writer->WriteLine("public Builder Set$0$($1$.Builder builderForValue) {",
+                    property_name(), type_name());
+  AddNullCheck(writer, "builderForValue");
+  writer->WriteLine("  PrepareBuilder();");
+  writer->WriteLine("  result.$0$Case_ = $1$OneofCase.$2$;",
+		    oneof_name(), oneof_property_name(), property_name());
+  writer->WriteLine("  result.$0$_ = builderForValue.Build();", oneof_name());
+  writer->WriteLine("  return this;");
+  writer->WriteLine("}");
+  AddDeprecatedFlag(writer);
+  writer->WriteLine("public Builder Merge$0$($1$ value) {", property_name(),
+                    type_name());
+  AddNullCheck(writer);
+  writer->WriteLine("  PrepareBuilder();");
+  writer->WriteLine("  if (result.$0$ &&", has_property_check);
+  writer->WriteLine("      result.$0$ != $1$) {", property_name(), default_value());
+  writer->WriteLine(
+      "    result.$0$_ = $1$.CreateBuilder(result.$2$).MergeFrom(value).BuildPartial();",
+      oneof_name(), type_name(), property_name());
+  writer->WriteLine("  } else {");
+  writer->WriteLine("    result.$0$_ = value;", oneof_name());
+  writer->WriteLine("  }");
+  writer->WriteLine("  result.$0$Case_ = $1$OneofCase.$2$;",
+		    oneof_name(), oneof_property_name(), property_name());
+  writer->WriteLine("  return this;");
+  writer->WriteLine("}");
+  AddDeprecatedFlag(writer);
+  writer->WriteLine("public Builder Clear$0$() {", property_name());
+  writer->WriteLine("  if (result.$0$) {", has_property_check);
+  writer->WriteLine("    PrepareBuilder();");
+  writer->WriteLine("    result.$0$Case_ = $1$OneofCase.None;",
+		    oneof_name(), oneof_property_name());
+  writer->WriteLine("    result.$0$_ = null;", oneof_name());
+  writer->WriteLine("  }");
+  writer->WriteLine("  return this;");
+  writer->WriteLine("}");
+}
+
+void MessageOneofFieldGenerator::GenerateParsingCode(Writer* writer) {
+  writer->WriteLine("$0$.Builder subBuilder = $0$.CreateBuilder();",
+                    type_name());
+  writer->WriteLine("if (result.$0$) {", has_property_check);
+  writer->WriteLine("  subBuilder.MergeFrom($0$);", property_name());
+  writer->WriteLine("}");
+
+  if (descriptor_->type() == FieldDescriptor::TYPE_GROUP) {
+    writer->WriteLine("input.ReadGroup($0$, subBuilder, extensionRegistry);",
+                      number());
+  } else {
+    writer->WriteLine("input.ReadMessage(subBuilder, extensionRegistry);");
+  }
+  writer->WriteLine("result.$0$_ = subBuilder.BuildPartial();", oneof_name());
+  writer->WriteLine("result.$0$Case_ = $1$OneofCase.$2$;",
+		    oneof_name(), oneof_property_name(), property_name());
+}
+
+void MessageOneofFieldGenerator::WriteEquals(Writer* writer) {
+  writer->WriteLine("if (!$0$.Equals(other.$0$)) return false;", property_name());
+}
+void MessageOneofFieldGenerator::WriteToString(Writer* writer) {
+  writer->WriteLine("PrintField(\"$0$\", $1$, $2$_, writer);",
+                    descriptor_->name(), has_property_check, oneof_name());
+}
+
 }  // namespace csharp
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/csharp/csharp_message_field.h b/src/google/protobuf/compiler/csharp/csharp_message_field.h
index 48bf8be5..d455ade5 100644
--- a/src/google/protobuf/compiler/csharp/csharp_message_field.h
+++ b/src/google/protobuf/compiler/csharp/csharp_message_field.h
@@ -60,10 +60,28 @@ class MessageFieldGenerator : public FieldGeneratorBase {
   virtual void WriteEquals(Writer* writer);
   virtual void WriteToString(Writer* writer);
 
+ protected:
+  string has_property_check;
+
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MessageFieldGenerator);
 };
 
+class MessageOneofFieldGenerator : public MessageFieldGenerator {
+ public:
+  MessageOneofFieldGenerator(const FieldDescriptor* descriptor, int fieldOrdinal);
+  ~MessageOneofFieldGenerator();
+
+  virtual void GenerateMembers(Writer* writer);
+  virtual void GenerateBuilderMembers(Writer* writer);
+  virtual void WriteEquals(Writer* writer);
+  virtual void WriteToString(Writer* writer);
+  virtual void GenerateParsingCode(Writer* writer);
+
+ private:
+  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MessageOneofFieldGenerator);
+};
+
 }  // namespace csharp
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/csharp/csharp_primitive_field.cc b/src/google/protobuf/compiler/csharp/csharp_primitive_field.cc
index a193afda..a54edfe3 100644
--- a/src/google/protobuf/compiler/csharp/csharp_primitive_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_primitive_field.cc
@@ -50,6 +50,11 @@ namespace csharp {
 PrimitiveFieldGenerator::PrimitiveFieldGenerator(
     const FieldDescriptor* descriptor, int fieldOrdinal)
     : FieldGeneratorBase(descriptor, fieldOrdinal) {
+  if (SupportFieldPresence(descriptor_->file())) {
+    has_property_check = "has" + property_name();
+  } else {
+    has_property_check = property_name() + " != " + default_value();
+  }
 }
 
 PrimitiveFieldGenerator::~PrimitiveFieldGenerator() {
@@ -133,11 +138,7 @@ void PrimitiveFieldGenerator::GenerateParsingCode(Writer* writer) {
 }
 
 void PrimitiveFieldGenerator::GenerateSerializationCode(Writer* writer) {
-  if (SupportFieldPresence(descriptor_->file())) {
-    writer->WriteLine("if (has$0$) {", property_name());
-  } else {
-    writer->WriteLine("if ($0$ != $1$) {", property_name(), default_value());
-  }
+  writer->WriteLine("if ($0$) {", has_property_check);
   writer->WriteLine("  output.Write$0$($1$, field_names[$3$], $2$);",
                     capitalized_type_name(), number(), property_name(),
                     field_ordinal());
@@ -145,22 +146,14 @@ void PrimitiveFieldGenerator::GenerateSerializationCode(Writer* writer) {
 }
 
 void PrimitiveFieldGenerator::GenerateSerializedSizeCode(Writer* writer) {
-  if (SupportFieldPresence(descriptor_->file())) {
-    writer->WriteLine("if (has$0$) {", property_name());
-  } else {
-    writer->WriteLine("if ($0$ != $1$) {", property_name(), default_value());
-  }
+  writer->WriteLine("if ($0$) {", has_property_check);
   writer->WriteLine("  size += pb::CodedOutputStream.Compute$0$Size($1$, $2$);",
                     capitalized_type_name(), number(), property_name());
   writer->WriteLine("}");
 }
 
 void PrimitiveFieldGenerator::WriteHash(Writer* writer) {
-  if (SupportFieldPresence(descriptor_->file())) {
-    writer->WriteLine("if (has$0$) {", property_name());
-  } else {
-    writer->WriteLine("if ($0$ != $1$) {", property_name(), default_value());
-  }
+  writer->WriteLine("if ($0$) {", has_property_check);
   writer->WriteLine("  hash ^= $0$_.GetHashCode();", name());
   writer->WriteLine("}");
 }
@@ -175,13 +168,84 @@ void PrimitiveFieldGenerator::WriteEquals(Writer* writer) {
   }
 }
 void PrimitiveFieldGenerator::WriteToString(Writer* writer) {
+  writer->WriteLine("PrintField(\"$0$\", $1$, $2$_, writer);",
+                    descriptor_->name(), has_property_check, name());
+}
+
+PrimitiveOneofFieldGenerator::PrimitiveOneofFieldGenerator(
+    const FieldDescriptor* descriptor, int fieldOrdinal)
+    : PrimitiveFieldGenerator(descriptor, fieldOrdinal) {
+  has_property_check = oneof_name() + "Case_ == " + oneof_property_name() +
+    "OneofCase." + property_name();
+}
+
+PrimitiveOneofFieldGenerator::~PrimitiveOneofFieldGenerator() {
+}
+
+void PrimitiveOneofFieldGenerator::GenerateMembers(Writer* writer) {
+  AddDeprecatedFlag(writer);
   if (SupportFieldPresence(descriptor_->file())) {
-    writer->WriteLine("PrintField(\"$0$\", has$1$, $2$_, writer);",
-                      descriptor_->name(), property_name(), name());
-  } else {
-    writer->WriteLine("PrintField(\"$0$\", $1$_, writer);",
-                      descriptor_->name(), name());
+    writer->WriteLine("public bool Has$0$ {", property_name());
+    writer->WriteLine("  get { return $0$; }", has_property_check);
+    writer->WriteLine("}");
   }
+  AddPublicMemberAttributes(writer);
+  writer->WriteLine("public $0$ $1$ {", type_name(), property_name());
+  writer->WriteLine("  get { return $0$ ? ($1$) $2$_ : $3$; }",
+		    has_property_check, type_name(), oneof_name(), default_value());
+  writer->WriteLine("}");
+}
+
+void PrimitiveOneofFieldGenerator::GenerateBuilderMembers(Writer* writer) {
+  AddDeprecatedFlag(writer);
+  if (SupportFieldPresence(descriptor_->file())) {
+    writer->WriteLine("public bool Has$0$ {", property_name());
+    writer->WriteLine("  get { return result.$0$; }", has_property_check);
+    writer->WriteLine("}");
+  }
+  AddPublicMemberAttributes(writer);
+  writer->WriteLine("public $0$ $1$ {", type_name(), property_name());
+  writer->WriteLine("  get { return result.$0$ ? ($1$) result.$2$_ : $3$; }",
+		    has_property_check, type_name(), oneof_name(), default_value());
+  writer->WriteLine("  set { Set$0$(value); }", property_name());
+  writer->WriteLine("}");
+  AddPublicMemberAttributes(writer);
+  writer->WriteLine("public Builder Set$0$($1$ value) {", property_name(),
+                    type_name());
+  AddNullCheck(writer);
+  writer->WriteLine("  PrepareBuilder();");
+  writer->WriteLine("  result.$0$_ = value;", oneof_name());
+  writer->WriteLine("  result.$0$Case_ = $1$OneofCase.$2$;",
+                    oneof_name(), oneof_property_name(), property_name());
+  writer->WriteLine("  return this;");
+  writer->WriteLine("}");
+  AddDeprecatedFlag(writer);
+  writer->WriteLine("public Builder Clear$0$() {", property_name());
+  writer->WriteLine("  PrepareBuilder();");
+  writer->WriteLine("  if (result.$0$) {", has_property_check);
+  writer->WriteLine("    result.$0$Case_ = $1$OneofCase.None;",
+                    oneof_name(), oneof_property_name());
+  writer->WriteLine("  }");
+  writer->WriteLine("  return this;");
+  writer->WriteLine("}");
+}
+
+void PrimitiveOneofFieldGenerator::WriteEquals(Writer* writer) {
+  writer->WriteLine("if (!$0$.Equals(other.$0$)) return false;", property_name());
+}
+void PrimitiveOneofFieldGenerator::WriteToString(Writer* writer) {
+  writer->WriteLine("PrintField(\"$0$\", $1$, $2$_, writer);",
+                    descriptor_->name(), has_property_check, oneof_name());
+}
+
+void PrimitiveOneofFieldGenerator::GenerateParsingCode(Writer* writer) {
+  writer->WriteLine("$0$ value = $1$;", type_name(), default_value());
+  writer->WriteLine("if (input.Read$0$(ref value)) {",
+		    capitalized_type_name());
+  writer->WriteLine("  result.$0$_ = value;", oneof_name());
+  writer->WriteLine("  result.$0$Case_ = $1$OneofCase.$2$;",
+		    oneof_name(), oneof_property_name(), property_name());
+  writer->WriteLine("}");
 }
 
 }  // namespace csharp
diff --git a/src/google/protobuf/compiler/csharp/csharp_primitive_field.h b/src/google/protobuf/compiler/csharp/csharp_primitive_field.h
index fb27ab43..ecc6ed91 100644
--- a/src/google/protobuf/compiler/csharp/csharp_primitive_field.h
+++ b/src/google/protobuf/compiler/csharp/csharp_primitive_field.h
@@ -60,10 +60,28 @@ class PrimitiveFieldGenerator : public FieldGeneratorBase {
   virtual void WriteEquals(Writer* writer);
   virtual void WriteToString(Writer* writer);
 
+ protected:
+  string has_property_check;
+
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(PrimitiveFieldGenerator);
 };
 
+class PrimitiveOneofFieldGenerator : public PrimitiveFieldGenerator {
+ public:
+  PrimitiveOneofFieldGenerator(const FieldDescriptor* descriptor, int fieldOrdinal);
+  ~PrimitiveOneofFieldGenerator();
+
+  virtual void GenerateMembers(Writer* writer);
+  virtual void GenerateBuilderMembers(Writer* writer);
+  virtual void WriteEquals(Writer* writer);
+  virtual void WriteToString(Writer* writer);
+  virtual void GenerateParsingCode(Writer* writer);
+
+ private:
+  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(PrimitiveOneofFieldGenerator);
+};
+
 }  // namespace csharp
 }  // namespace compiler
 }  // namespace protobuf