1 files changed, 12 insertions, 0 deletions
diff --git a/src/google/protobuf/compiler/csharp/csharp_field_base.cc b/src/google/protobuf/compiler/csharp/csharp_field_base.cc
index 914b972d..f36e6fde 100644
--- a/src/google/protobuf/compiler/csharp/csharp_field_base.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_field_base.cc
@@ -168,6 +168,18 @@ std::string FieldGeneratorBase::type_name(const FieldDescriptor* descriptor) {
       return GetClassName(descriptor->enum_type());
     case FieldDescriptor::TYPE_MESSAGE:
     case FieldDescriptor::TYPE_GROUP:
+      if (IsWrapperType(descriptor)) {
+        const FieldDescriptor* wrapped_field = descriptor->message_type()->field(0);
+        string wrapped_field_type_name = type_name(wrapped_field);
+        // String and ByteString go to the same type; other wrapped types go to the
+        // nullable equivalent.
+        if (wrapped_field->type() == FieldDescriptor::TYPE_STRING ||
+            wrapped_field->type() == FieldDescriptor::TYPE_BYTES) {
+          return wrapped_field_type_name;
+        } else {
+          return wrapped_field_type_name + "?";
+        }
+      }
       return GetClassName(descriptor->message_type());
     case FieldDescriptor::TYPE_DOUBLE:
       return "double";