feat: applying suggestions

lib/game/components/ball.dart

@@ -29,13 +29,12 @@ class Ball extends BodyComponent<PinballGame>
     return world.createBody(bodyDef)..createFixture(fixtureDef);
   }
 
-  void ballLost() {
-    final bloc = gameRef.read<GameBloc>();
+  void lost() {
+    shouldRemove = true;
 
-    final shouldBallRespwan = !bloc.state.isLastBall;
-
-    bloc.add(const BallLost());
+    final bloc = gameRef.read<GameBloc>()..add(const BallLost());
 
+    final shouldBallRespwan = !bloc.state.isLastBall;
     if (shouldBallRespwan) {
       gameRef.spawnBall();
     }

lib/game/components/wall.dart

@@ -3,32 +3,14 @@
 import 'package:flame_forge2d/flame_forge2d.dart';
 import 'package:pinball/game/components/components.dart';
 
-enum WallType {
-  fatal,
-  passive,
-}
-
 class Wall extends BodyComponent {
   Wall({
     required this.start,
     required this.end,
-    this.type = WallType.passive,
   });
 
-  factory Wall.bottom(Forge2DGame game) {
-    final bottomRight = game.screenToWorld(game.camera.viewport.effectiveSize);
-    final bottomLeft = Vector2(0, bottomRight.y);
-
-    return Wall(
-      type: WallType.fatal,
-      start: bottomRight,
-      end: bottomLeft,
-    );
-  }
-
   final Vector2 start;
   final Vector2 end;
-  final WallType type;
 
   @override
   Body createBody() {
@@ -47,14 +29,21 @@ class Wall extends BodyComponent {
   }
 }
 
-class BallWallContactCallback extends ContactCallback<Ball, Wall> {
+class BottomWall extends Wall {
+  BottomWall(Forge2DGame game)
+      : super(
+          start: game.screenToWorld(game.camera.viewport.effectiveSize),
+          end: Vector2(
+            0,
+            game.screenToWorld(game.camera.viewport.effectiveSize).y,
+          ),
+        );
+}
+
+class BottomWallBallContactCallback extends ContactCallback<Ball, BottomWall> {
   @override
-  void begin(Ball ball, Wall wall, Contact contact) {
-    if (wall.type == WallType.fatal) {
-      ball
-        ..ballLost()
-        ..shouldRemove = true;
-    }
+  void begin(Ball ball, BottomWall wall, Contact contact) {
+    ball.lost();
   }
 
   @override

lib/game/pinball_game.dart

@@ -21,7 +21,7 @@ class PinballGame extends Forge2DGame with FlameBloc {
     spawnBall();
     addContactCallback(BallScorePointsCallback());
 
-    await add(Wall.bottom(this));
-    addContactCallback(BallWallContactCallback());
+    await add(BottomWall(this));
+    addContactCallback(BottomWallBallContactCallback());
   }
 }

test/game/components/ball_test.dart

@@ -107,7 +107,7 @@ void main() {
         (game, tester) async {
           await game.ready();
 
-          game.children.whereType<Ball>().first.ballLost();
+          game.children.whereType<Ball>().first.lost();
           await tester.pump();
 
           verify(() => gameBloc.add(const BallLost())).called(1);

test/game/components/wall_test.dart

@@ -12,24 +12,23 @@ void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
 
   group('Wall', () {
-    group('BallWallContactCallback', () {
+    group('BottomWallBallContactCallback', () {
       test(
-        'removes the ball on begin contact when the wall is a fatal one',
+        'removes the ball on begin contact when the wall is a bottom one',
         () {
           final game = MockPinballGame();
-          final wall = MockWall();
+          final wall = MockBottomWall();
           final ball = MockBall();
 
-          when(() => wall.type).thenReturn(WallType.fatal);
           when(() => ball.gameRef).thenReturn(game);
 
-          BallWallContactCallback()
+          BottomWallBallContactCallback()
             // Remove once https://github.com/flame-engine/flame/pull/1415
             // is merged
-            ..end(MockBall(), MockWall(), MockContact())
+            ..end(MockBall(), MockBottomWall(), MockContact())
             ..begin(ball, wall, MockContact());
 
-          verify(() => ball.shouldRemove = true).called(1);
+          verify(ball.lost).called(1);
         },
       );
     });

test/helpers/mocks.dart

@@ -6,6 +6,8 @@ class MockPinballGame extends Mock implements PinballGame {}
 
 class MockWall extends Mock implements Wall {}
 
+class MockBottomWall extends Mock implements BottomWall {}
+
 class MockBall extends Mock implements Ball {}
 
 class MockContact extends Mock implements Contact {}