to fix distinctBy for scala 2.12

Author: fupelaqu

sql/src/main/scala/app/softnetwork/elastic/sql/query/From.scala

@@ -215,7 +215,7 @@ object NestedElements {
     val nestedParentsPath: collection.mutable.Map[String, (NestedElement, Seq[NestedElement])] =
       collection.mutable.Map.empty
 
-    val distinctNestedElements = nestedElements.distinctBy(_.path)
+    val distinctNestedElements = nestedElements.groupBy(_.path).map(_._2.head).toList
 
     @tailrec
     def getNestedParents(

sql/src/main/scala/app/softnetwork/elastic/sql/query/Having.scala

@@ -15,5 +15,5 @@ case class Having(criteria: Option[Criteria]) extends Updateable {
   override def validate(): Either[String, Unit] = criteria.map(_.validate()).getOrElse(Right(()))
 
   def nestedElements: Seq[NestedElement] =
-    criteria.map(_.nestedElements).getOrElse(Seq.empty).distinctBy(_.path)
+    criteria.map(_.nestedElements).getOrElse(Seq.empty).groupBy(_.path).map(_._2.head).toList
 }

sql/src/main/scala/app/softnetwork/elastic/sql/query/SQLSearchRequest.scala

@@ -29,12 +29,17 @@ case class SQLSearchRequest(
       .filterNot(_.aggregation)
       .filter(_.nested)
       .groupBy(_.identifier.innerHitsName.getOrElse(""))
-  lazy val nested: Seq[NestedElement] = from.unnests.map(toNestedElement).distinctBy(_.path)
+  lazy val nested: Seq[NestedElement] =
+    from.unnests.map(toNestedElement).groupBy(_.path).map(_._2.head).toList
   private[this] lazy val nestedFieldsWithoutCriteria: Map[String, Seq[Field]] = {
     // nested fields that are not part of where, having or group by clauses
     val innerHitsWithCriteria = (where.map(_.nestedElements).getOrElse(Seq.empty) ++
       having.map(_.nestedElements).getOrElse(Seq.empty) ++
-      groupBy.map(_.nestedElements).getOrElse(Seq.empty)).distinctBy(_.path).map(_.innerHitsName)
+      groupBy.map(_.nestedElements).getOrElse(Seq.empty))
+      .groupBy(_.path)
+      .map(_._2.head)
+      .toList
+      .map(_.innerHitsName)
     val ret = nestedFields.filterNot { case (innerHitsName, _) =>
       innerHitsWithCriteria.contains(innerHitsName)
     }

sql/src/main/scala/app/softnetwork/elastic/sql/query/Where.scala

@@ -790,7 +790,7 @@ case class Where(criteria: Option[Criteria]) extends Updateable {
   }
 
   def nestedElements: Seq[NestedElement] = criteria match {
-    case Some(c) => c.nestedElements.distinctBy(_.path)
+    case Some(c) => c.nestedElements.groupBy(_.path).map(_._2.head).toList
     case _       => Nil
   }
 }