fix game variant when from a position

modules/setup/src/main/Config.scala

@@ -1,6 +1,7 @@
 package lila.setup
 
 import chess.{ Game => ChessGame, Situation, Clock, Speed }
+import chess.variant.FromPosition
 
 import lila.game.Game
 import lila.lobby.Color
@@ -54,12 +55,14 @@ trait Positional { self: Config =>
 
   def strictFen: Boolean
 
-  lazy val validFen = variant != chess.variant.FromPosition || {
+  lazy val validFen = variant != FromPosition || {
     fen ?? { f => ~(Forsyth <<< f).map(_.situation playable strictFen) }
   }
 
   def fenGame(builder: ChessGame => Game): Game = {
-    val baseState = fen ifTrue (variant == chess.variant.FromPosition) flatMap Forsyth.<<<
+    val baseState = fen ifTrue (variant == FromPosition) flatMap {
+      Forsyth.<<<@(FromPosition, _)
+    }
     val (chessGame, state) = baseState.fold(makeGame -> none[SituationPlus]) {
       case sit @ SituationPlus(s, _) =>
         val game = ChessGame(
@@ -78,7 +81,7 @@ trait Positional { self: Config =>
           situation = game.situation.copy(
             board = game.board.copy(
               history = board.history,
-              variant = chess.variant.FromPosition
+              variant = FromPosition
             )
           ),
           turns = sit.turns
@@ -94,7 +97,7 @@ trait BaseConfig {
   val variants = List(chess.variant.Standard.id, chess.variant.Chess960.id)
   val variantDefault = chess.variant.Standard
 
-  val variantsWithFen = variants :+ chess.variant.FromPosition.id
+  val variantsWithFen = variants :+ FromPosition.id
   val aiVariants = variants :+
     chess.variant.Crazyhouse.id :+
     chess.variant.KingOfTheHill.id :+
@@ -114,7 +117,7 @@ trait BaseConfig {
       chess.variant.Horde.id :+
       chess.variant.RacingKings.id
   val variantsWithFenAndVariants =
-    variantsWithVariants :+ chess.variant.FromPosition.id
+    variantsWithVariants :+ FromPosition.id
 
   val speeds = Speed.all map (_.id)