add comment per review suggestion; add another in the same vein, for …

…clarity
bufbuild · Apr 8, 2024 · 2e63fc4 · 2e63fc4
1 parent 897e7c5
commit 2e63fc4
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/linker/descriptors.go b/linker/descriptors.go
@@ -1048,6 +1048,8 @@ func (f *fldDescriptor) Cardinality() protoreflect.Cardinality {
 		return protoreflect.Required
 	case descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL:
 		if f.Syntax() == protoreflect.Editions {
+			// Editions does not use label to indicate required. It instead
+			// uses a feature, and label is always optional.
 			fieldPresence := descriptorpb.FeatureSet_FieldPresence(resolveFeature(f, fieldPresenceField).Enum())
 			if fieldPresence == descriptorpb.FeatureSet_LEGACY_REQUIRED {
 				return protoreflect.Required
@@ -1061,6 +1063,8 @@ func (f *fldDescriptor) Cardinality() protoreflect.Cardinality {
 
 func (f *fldDescriptor) Kind() protoreflect.Kind {
 	if f.proto.GetType() == descriptorpb.FieldDescriptorProto_TYPE_MESSAGE && f.Syntax() == protoreflect.Editions {
+		// In editions, "group encoding" (aka "delimited encoding") is toggled
+		// via a feature. So we report group kind when that feature is enabled.
 		messageEncoding := resolveFeature(f, messageEncodingField)
 		if descriptorpb.FeatureSet_MessageEncoding(messageEncoding.Enum()) == descriptorpb.FeatureSet_DELIMITED {
 			return protoreflect.GroupKind