descriptor.proto in grpc-tools-1.30.0.pre1

- old
+ new

@@ -127,10 +127,11 @@
 
 message ExtensionRangeOptions {
   // The parser stores options it doesn't recognize here. See above.
   repeated UninterpretedOption uninterpreted_option = 999;
 
+
   // Clients can define custom options in extensions of this message. See above.
   extensions 1000 to max;
 }
 
 // Describes a field within a message.
@@ -210,10 +211,33 @@
   // will be used. Otherwise, it's deduced from the field's name by converting
   // it to camelCase.
   optional string json_name = 10;
 
   optional FieldOptions options = 8;
+
+  // If true, this is a proto3 "optional". When a proto3 field is optional, it
+  // tracks presence regardless of field type.
+  //
+  // When proto3_optional is true, this field must be belong to a oneof to
+  // signal to old proto3 clients that presence is tracked for this field. This
+  // oneof is known as a "synthetic" oneof, and this field must be its sole
+  // member (each proto3 optional field gets its own synthetic oneof). Synthetic
+  // oneofs exist in the descriptor only, and do not generate any API. Synthetic
+  // oneofs must be ordered after all "real" oneofs.
+  //
+  // For message fields, proto3_optional doesn't create any semantic change,
+  // since non-repeated message fields always track presence. However it still
+  // indicates the semantic detail of whether the user wrote "optional" or not.
+  // This can be useful for round-tripping the .proto file. For consistency we
+  // give message fields a synthetic oneof also, even though it is not required
+  // to track presence. This is especially important because the parser can't
+  // tell if a field is a message or an enum, so it must always create a
+  // synthetic oneof.
+  //
+  // Proto2 optional fields do not set this flag, because they already indicate
+  // optional with `LABEL_OPTIONAL`.
+  optional bool proto3_optional = 17;
 }
 
 // Describes a oneof.
 message OneofDescriptorProto {
   optional string name = 1;
@@ -391,10 +415,10 @@
   // least, this is a formalization for deprecating files.
   optional bool deprecated = 23 [default = false];
 
   // Enables the use of arenas for the proto messages in this file. This applies
   // only to generated classes for C++.
-  optional bool cc_enable_arenas = 31 [default = false];
+  optional bool cc_enable_arenas = 31 [default = true];
 
 
   // Sets the objective c class prefix which is prepended to all objective c
   // generated classes from this .proto. There is no default.
   optional string objc_class_prefix = 36;