remove StructField.toString

Author: mengxr

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/types/dataTypes.scala

@@ -401,11 +401,6 @@ case class StructField(
     DataType.buildFormattedString(dataType, s"$prefix    |", builder)
   }
 
-  override def toString: String = {
-    // Do not add metadata to be consistent with CaseClassStringParser.
-    s"StructField($name,$dataType,$nullable)"
-  }
-
   private[sql] def jsonValue: JValue = {
     ("name" -> name) ~
       ("type" -> dataType.jsonValue) ~

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/Metadata.scala

@@ -153,7 +153,7 @@ object Metadata {
   private def toJsonValue(obj: Any): JValue = {
     obj match {
       case map: Map[_, _] =>
-        val fields = map.toList.map { case (k: String, v) => (k, toJsonValue(v))}
+        val fields = map.toList.map { case (k: String, v) => (k, toJsonValue(v)) }
         JObject(fields)
       case arr: Array[_] =>
         val values = arr.toList.map(toJsonValue)