Add test for outcome summary

src/main/kotlin/rps/Game.kt

@@ -24,9 +24,14 @@ enum class Outcome {
   LOSS
 }
 
+// Named Triple for readability
+data class GameSummary(val wins: Int, val draws: Int, val losses: Int)
+
 /** Determine the [Outcome] of [first] vs [second] from the perspective of [first]. */
 fun determineOutcome(first: Move, second: Move): Outcome = when {
   first.strongAgainst() == second -> Outcome.WIN
   first == second -> Outcome.DRAW
   else -> Outcome.LOSS
-}
+}
+
+fun calculateGameSummary(turns: List<Outcome>): GameSummary = TODO()

src/test/kotlin/rps/GameTest.kt

@@ -18,4 +18,17 @@ class GameTest {
       assertEquals(determineOutcome(first, second), expected)
     }
   }
+
+  @Test
+  fun `game summary should count outcomes`() {
+    val gameLists = listOf(
+        listOf(WIN, WIN, WIN) to GameSummary(3, 0, 0),
+        listOf(WIN, DRAW, LOSS) to GameSummary(1, 1, 1),
+        listOf(WIN, LOSS, WIN) to GameSummary(2, 0, 1),
+        listOf(WIN, DRAW, DRAW, DRAW) to GameSummary(1, 3, 0),
+    )
+    for ((outcomes, expectedSummary) in gameLists) {
+      assertEquals(calculateGameSummary(outcomes), expectedSummary)
+    }
+  }
 }