PlayerHand test

src/main/kotlin/eventDemo/app/entity/PlayerHand.kt

@@ -2,7 +2,7 @@ package eventDemo.app.entity
 
 typealias PlayerHands = Map<Player, List<Card>>
 
-fun PlayerHands.addCard(
+fun PlayerHands.removeCard(
     player: Player,
     card: Card,
 ) = mapValues { (p, cards) ->
@@ -12,3 +12,14 @@ fun PlayerHands.addCard(
         cards
     }
 }
+
+fun PlayerHands.addCards(
+    player: Player,
+    newCards: List<Card>,
+) = mapValues { (p, cards) ->
+    if (p == player) {
+        cards + newCards
+    } else {
+        cards
+    }
+}

src/test/kotlin/eventDemo/app/entity/PlayerHandKtTest.kt

@@ -0,0 +1,42 @@
+package eventDemo.app.entity
+
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.ints.shouldBeExactly
+import kotlin.test.assertNotNull
+
+class PlayerHandKtTest :
+    FunSpec({
+        test("addCards") {
+            // Given
+            val playerNumbers = 4
+            val players = (1..playerNumbers).map { Player(name = "name $it") }.toSet()
+            val firstPlayer = players.first()
+            val playersHands: PlayerHands = players.associateWith { emptyList() }
+            val card = Card.NumericCard(0, Card.Color.Red)
+
+            // When
+            val newHands: PlayerHands = playersHands.addCards(firstPlayer, listOf(card))
+
+            assertNotNull(newHands[firstPlayer]).size shouldBeExactly 1
+            assertNotNull(newHands[players.last()]).size shouldBeExactly 0
+        }
+
+        test("removeCard") {
+            // Given
+            val playerNumbers = 4
+            val players = (1..playerNumbers).map { Player(name = "name $it") }.toSet()
+            val firstPlayer = players.first()
+            val card1 = Card.NumericCard(1, Card.Color.Red)
+            val card2 = Card.NumericCard(2, Card.Color.Red)
+            val playersHands: PlayerHands =
+                players
+                    .associateWith<Player, List<Card>> { emptyList() }
+                    .addCards(firstPlayer, listOf(card1, card2))
+
+            // When
+            val newHands: PlayerHands = playersHands.removeCard(firstPlayer, card1)
+
+            assertNotNull(newHands[firstPlayer]).size shouldBeExactly 1
+            assertNotNull(newHands[players.last()]).size shouldBeExactly 0
+        }
+    })