diff --git a/util/proto/marshal_test.go b/util/proto/marshal_test.go
index de2b72fc..11a4d8f8 100644
--- a/util/proto/marshal_test.go
+++ b/util/proto/marshal_test.go
@@ -37,8 +37,8 @@ type stableRepPrimitives struct {
 
 const (
 	ENUM_UNKNOWN  SomeEnum = 0
-	ENUM_POSITIVE          = 1
-	ENUM_NEGATIVE          = -1
+	ENUM_POSITIVE SomeEnum = 1
+	ENUM_NEGATIVE SomeEnum = -1
 )
 
 func (s *stablePrimitives) stableMarshal(buf []byte, wrongField bool) ([]byte, error) {