tree 16010fd7a767bb7ad8d6852243b6e1719d41dc18
parent b57aae9defbc3e3ce7daed74b0c4d7a57550c933
author Joe Tsai <joetsai@digital-static.net> 1588110278 -0700
committer Joe Tsai <thebrokentoaster@gmail.com> 1588190544 +0000

all: implement support for proto3 optional semantics

In the upcoming 3.12.x release of protoc, the proto3 language will be
amended to support true presence for scalars. This CL adds support
to both the generator and runtime to support these semantics.

Newly added public API:
	protogen.Plugin.SupportedFeatures
	protoreflect.FieldDescriptor.HasPresence
	protoreflect.FieldDescriptor.HasOptionalKeyword
	protoreflect.OneofDescriptor.IsSynthetic

Change-Id: I7c86bf66d0ae56642109beb5f2132184593747ad
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/230698
Reviewed-by: Damien Neil <dneil@google.com>