cmd/protoc-gen-go: improve generation of comments
The following improvements were made:
* All standalone comments above the "syntax" marker are preserved
similar to Java and some other generators.
* All standalone comments above the "package" marker are preserved
to be consistent with our former behavior.
* Leading comments are now generated for enums and extension fields.
* Single-line trailing comments are now generated for
enum values, message fields, and extension fields.
* The leading comments for each field that is part of a oneof are now
generated with the wrapper types rather than being shoved into the
comment for the oneof itself in an unreadable way.
* The deprecation marker is always generated as being above the declaration
rather than sometimes being an inlined comment.
* The deprecation marker is now properly generated for weak field setters.
Updates golang/protobuf#666
Change-Id: I7fd832dd4f86d15bfff70d7c22c6ba4934c05fcf
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/189238
Reviewed-by: Damien Neil <dneil@google.com>
diff --git a/internal/testprotos/test/ext.pb.go b/internal/testprotos/test/ext.pb.go
index 7922170..395ce91 100644
--- a/internal/testprotos/test/ext.pb.go
+++ b/internal/testprotos/test/ext.pb.go
@@ -1,3 +1,7 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
// Code generated by protoc-gen-go. DO NOT EDIT.
// source: test/ext.proto