diff --git a/spark/src/test/scala/org/apache/spark/sql/delta/DeltaProtocolVersionSuite.scala b/spark/src/test/scala/org/apache/spark/sql/delta/DeltaProtocolVersionSuite.scala
index 94d42786163..0b822e792f0 100644
--- a/spark/src/test/scala/org/apache/spark/sql/delta/DeltaProtocolVersionSuite.scala
+++ b/spark/src/test/scala/org/apache/spark/sql/delta/DeltaProtocolVersionSuite.scala
@@ -3493,8 +3493,8 @@ trait DeltaProtocolVersionSuiteBase extends QueryTest
     }
   }
 
-  def validVersions = Seq((1, 1), (1, 2), (1, 3), (1, 4), (2, 5), (2, 6), (1, 7), (3, 7))
-  def invalidVersions = Seq((2, 2), (2, 3))
+  private def validVersions = Seq((1, 1), (1, 2), (1, 3), (1, 4), (2, 5), (2, 6), (1, 7), (3, 7))
+  private def invalidVersions = Seq((2, 2), (2, 3))
   for ((readerVersion, writerVersion) <- validVersions ++ invalidVersions)
   test(s"Legacy features are added when setting legacy versions: " +
       s"readerVersionToSet = $readerVersion, writerVersionToSet = $writerVersion") {