test and fix featured game heuristics

app/game/Featured.scala

@@ -64,11 +64,9 @@ object Featured {
 
   case object GetOne
 
-  def best(games: List[DbGame]) = (games sortBy { game ⇒
-    1 - score(game)
-    }).headOption 
+  def best(games: List[DbGame]) = (games sortBy score).lastOption
 
-  private def score(game: DbGame): Float = heuristics map {
+  def score(game: DbGame): Float = heuristics map {
     case (fn, coefficient) ⇒ heuristicBox(fn(game)) * coefficient
   } sum
 
@@ -76,7 +74,7 @@ object Featured {
   private val heuristicBox = box(0 to 1) _
   private val eloBox = box(1200 to 2000) _
   private val timeBox = box(60 to 300) _
-  private val turnBox = box(1 to 20) _
+  private val turnBox = box(1 to 21) _
 
   private val heuristics: List[(Heuristic, Float)] = List(
     eloHeuristic(Color.White) -> 1,
@@ -84,16 +82,16 @@ object Featured {
     speedHeuristic -> 1,
     progressHeuristic -> 0.5f)
 
-  private def eloHeuristic(color: Color): Heuristic = game ⇒
+  def eloHeuristic(color: Color): Heuristic = game ⇒
     eloBox(game.player(color).eloEstimation)
 
-  private def speedHeuristic: Heuristic = game ⇒
+  def speedHeuristic: Heuristic = game ⇒
     1 - timeBox(game.estimateTotalTime)
 
-  private def progressHeuristic: Heuristic = game ⇒
+  def progressHeuristic: Heuristic = game ⇒
     1 - turnBox(game.turns)
 
   // boxes and reduce to 0..1 range
-  private def box(in: Range.Inclusive)(v: Float): Float =
-    math.max(in.start, math.min(v, in.end)) - in.start / (in.end - in.start).toFloat
+  def box(in: Range.Inclusive)(v: Float): Float =
+    (math.max(in.start, math.min(v, in.end)) - in.start) / (in.end - in.start).toFloat
 }

test/FeaturedTest.scala

@@ -0,0 +1,106 @@
+package lila
+package game
+
+import game._
+
+class FeaturedTest extends LilaSpec {
+
+  import Featured._
+
+  "Featured" should {
+
+    "box 0 to 1" in {
+      foreach(List(
+        0f -> 0f,
+        1f -> 1f,
+        0.5f -> 0.5f,
+        0.9f -> 0.9f,
+        -1f -> 0f,
+        2f -> 1f)) {
+        case (a, b) ⇒ box(0 to 1)(a) must_== b
+      }
+    }
+
+    "box 1200 to 2000" in {
+      foreach(List(
+        1200f -> 0f,
+        2000f -> 1f,
+        1600f -> 0.5f,
+        1900f -> 0.875f,
+        -1f -> 0f,
+        800f -> 0f,
+        2200f -> 1f)) {
+        case (a, b) ⇒ box(1200 to 2000)(a) must_== b
+      }
+    }
+
+    val game1 = DbGame(
+      game = chess.Game(),
+      whitePlayer = DbPlayer.white.copy(elo = 1600.some),
+      blackPlayer = DbPlayer.black,
+      ai = None,
+      creatorColor = chess.Color.White,
+      mode = chess.Mode.default,
+      variant = chess.Variant.default)
+
+    val game2 = game1.copy(
+      clock = chess.Clock(180,0).some,
+      turns = 11)
+
+    val game3 = game1.copy(
+      clock = chess.Clock(60,0).some,
+      turns = 21)
+
+    val games = List(game1, game2, game3)
+
+    "elo" in {
+      "game1 white" in {
+        eloHeuristic(chess.Color.White)(game1) must_== 0.5f
+      }
+      "game1 black" in {
+        eloHeuristic(chess.Color.Black)(game1) must_== 0f
+      }
+    }
+    "speed" in {
+      "game1" in {
+        speedHeuristic(game1) must_== 0
+      }
+      "game2" in {
+        speedHeuristic(game2) must_== 0.5f
+      }
+      "game3" in {
+        speedHeuristic(game3) must_== 1f
+      }
+    }
+    "progress" in {
+      "game1" in {
+        progressHeuristic(game1) must_== 1f
+      }
+      "game2" in {
+        progressHeuristic(game2) must_== 0.5f
+      }
+      "game3" in {
+        progressHeuristic(game3) must_== 0f
+      }
+    }
+    "score" in {
+      "game1" in {
+        score(game1) must_== 0.5f + 0f + 1f * 0.5f
+      }
+      "game2" in {
+        score(game2) must_== 0.5f + 0.5f + 0.5f * 0.5f
+      }
+      "game3" in {
+        score(game3) must_== 0.5f + 1f + 0f * 0.5f
+      }
+    }
+    "best" in {
+      "3 games" in {
+        best(games) must_== game3.some
+      }
+      "3 games reversed" in {
+        best(games.reverse) must_== game3.some
+      }
+    }
+  }
+}

test/LilaSpec.scala

@@ -0,0 +1,9 @@
+package lila
+
+import org.specs2.mutable._
+import ornicar.scalalib.test.OrnicarValidationMatchers
+
+trait LilaSpec 
+extends Specification 
+with OrnicarValidationMatchers {
+}