feat(pinball_components): implemented LayerFilteringBehavior

packages/pinball_components/lib/src/components/layer_sensor/layer_sensor.dart

@@ -21,8 +21,7 @@ enum LayerEntranceOrientation {
 /// By default the base [layer] is set to [Layer.board] and the
 /// [outsideZIndex] is set to [ZIndexes.ballOnBoard].
 /// {@endtemplate}
-abstract class LayerSensor extends BodyComponent
+abstract class LayerSensor extends BodyComponent with InitialPosition, Layered {
-    with InitialPosition, Layered, ContactCallbacks {
   /// {@macro layer_sensor}
   LayerSensor({
     required this.insideLayer,
@@ -61,9 +60,7 @@ abstract class LayerSensor extends BodyComponent
       shape,
       isSensor: true,
     );
-    final bodyDef = BodyDef(
+    final bodyDef = BodyDef(position: initialPosition);
-      position: initialPosition,
-    );
     return world.createBody(bodyDef)..createFixture(fixtureDef);
   }
 }

packages/pinball_components/test/src/components/layer_sensor/behavior/layer_filtering_behavior_test.dart

@@ -0,0 +1,136 @@
+// ignore_for_file: cascade_invocations
+
+import 'package:flame_forge2d/flame_forge2d.dart';
+import 'package:flame_test/flame_test.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mocktail/mocktail.dart';
+import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_components/src/components/layer_sensor/behaviors/behaviors.dart';
+
+import '../../../../helpers/helpers.dart';
+
+class _TestLayerSensor extends LayerSensor {
+  _TestLayerSensor({
+    required LayerEntranceOrientation orientation,
+    required int insideZIndex,
+    required Layer insideLayer,
+  }) : super(
+          insideLayer: insideLayer,
+          insideZIndex: insideZIndex,
+          orientation: orientation,
+        );
+
+  @override
+  Shape get shape => PolygonShape()..setAsBoxXY(1, 1);
+}
+
+class _MockBall extends Mock implements Ball {}
+
+class _MockBody extends Mock implements Body {}
+
+class _MockContact extends Mock implements Contact {}
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+  final flameTester = FlameTester(TestGame.new);
+
+  group(
+    'LayerSensorBehavior',
+    () {
+      test('can be instantiated', () {
+        expect(
+          LayerFilteringBehavior(),
+          isA<LayerFilteringBehavior>(),
+        );
+      });
+
+      flameTester.test(
+        'loads',
+        (game) async {
+          final behavior = LayerFilteringBehavior();
+          final parent = _TestLayerSensor(
+            orientation: LayerEntranceOrientation.down,
+            insideZIndex: 1,
+            insideLayer: Layer.spaceshipEntranceRamp,
+          );
+
+          await parent.add(behavior);
+          await game.ensureAdd(parent);
+
+          expect(game.contains(parent), isTrue);
+        },
+      );
+
+      group('beginContact', () {
+        late Ball ball;
+        late Body body;
+        late int insideZIndex;
+        late Layer insideLayer;
+
+        setUp(() {
+          ball = _MockBall();
+          body = _MockBody();
+          insideZIndex = 1;
+          insideLayer = Layer.spaceshipEntranceRamp;
+
+          when(() => ball.body).thenReturn(body);
+          when(() => ball.layer).thenReturn(Layer.board);
+        });
+
+        flameTester.test(
+            'changes ball layer and zIndex '
+            'when a ball enters and exits a downward oriented LayerSensor',
+            (game) async {
+          final parent = _TestLayerSensor(
+            orientation: LayerEntranceOrientation.down,
+            insideZIndex: 1,
+            insideLayer: insideLayer,
+          )..initialPosition = Vector2(0, 10);
+          final behavior = LayerFilteringBehavior();
+
+          await parent.add(behavior);
+          await game.ensureAdd(parent);
+
+          when(() => body.linearVelocity).thenReturn(Vector2(0, -1));
+
+          behavior.beginContact(ball, _MockContact());
+          verify(() => ball.layer = insideLayer).called(1);
+          verify(() => ball.zIndex = insideZIndex).called(1);
+
+          when(() => ball.layer).thenReturn(insideLayer);
+
+          behavior.beginContact(ball, _MockContact());
+          verify(() => ball.layer = Layer.board);
+          verify(() => ball.zIndex = ZIndexes.ballOnBoard).called(1);
+        });
+
+        flameTester.test(
+            'changes ball layer and zIndex '
+            'when a ball enters and exits an upward oriented LayerSensor',
+            (game) async {
+          final parent = _TestLayerSensor(
+            orientation: LayerEntranceOrientation.up,
+            insideZIndex: 1,
+            insideLayer: insideLayer,
+          )..initialPosition = Vector2(0, 10);
+          final behavior = LayerFilteringBehavior();
+
+          await parent.add(behavior);
+          await game.ensureAdd(parent);
+
+          when(() => body.linearVelocity).thenReturn(Vector2(0, 1));
+
+          behavior.beginContact(ball, _MockContact());
+          verify(() => ball.layer = insideLayer).called(1);
+          verify(() => ball.zIndex = 1).called(1);
+
+          when(() => ball.layer).thenReturn(insideLayer);
+
+          behavior.beginContact(ball, _MockContact());
+          verify(() => ball.layer = Layer.board);
+          verify(() => ball.zIndex = ZIndexes.ballOnBoard).called(1);
+        });
+      });
+    },
+  );
+}

packages/pinball_components/test/src/components/layer_sensor/layer_sensor_test.dart

@@ -2,16 +2,10 @@
 import 'package:flame_forge2d/flame_forge2d.dart';
 import 'package:flame_test/flame_test.dart';
 import 'package:flutter_test/flutter_test.dart';
-import 'package:mocktail/mocktail.dart';
 import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_components/src/components/layer_sensor/behaviors/behaviors.dart';
 
-import '../../helpers/helpers.dart';
+import '../../../helpers/helpers.dart';
-
-class _MockBall extends Mock implements Ball {}
-
-class _MockBody extends Mock implements Body {}
-
-class _MockContact extends Mock implements Contact {}
 
 class TestLayerSensor extends LayerSensor {
   TestLayerSensor({
@@ -112,68 +106,22 @@ void main() {
         );
       });
     });
-  });
-
-  group('beginContact', () {
-    late Ball ball;
-    late Body body;
-    late int insideZIndex;
-    late Layer insideLayer;
-
-    setUp(() {
-      ball = _MockBall();
-      body = _MockBody();
-      insideZIndex = 1;
-      insideLayer = Layer.spaceshipEntranceRamp;
-
-      when(() => ball.body).thenReturn(body);
-      when(() => ball.layer).thenReturn(Layer.board);
-    });
-
-    flameTester.test(
-        'changes ball layer and zIndex '
-        'when a ball enters and exits a downward oriented LayerSensor',
-        (game) async {
-      final sensor = TestLayerSensor(
-        orientation: LayerEntranceOrientation.down,
-        insideZIndex: insidePriority,
-        insideLayer: insideLayer,
-      )..initialPosition = Vector2(0, 10);
-
-      when(() => body.linearVelocity).thenReturn(Vector2(0, -1));
-
-      sensor.beginContact(ball, _MockContact());
-      verify(() => ball.layer = insideLayer).called(1);
-      verify(() => ball.zIndex = insideZIndex).called(1);
-
-      when(() => ball.layer).thenReturn(insideLayer);
-
-      sensor.beginContact(ball, _MockContact());
-      verify(() => ball.layer = Layer.board);
-      verify(() => ball.zIndex = ZIndexes.ballOnBoard).called(1);
-    });
 
     flameTester.test(
-        'changes ball layer and zIndex '
+      'adds a LayerFilteringBehavior',
-        'when a ball enters and exits an upward oriented LayerSensor',
+      (game) async {
-        (game) async {
+        final layerSensor = TestLayerSensor(
-      final sensor = TestLayerSensor(
+          orientation: LayerEntranceOrientation.down,
-        orientation: LayerEntranceOrientation.up,
+          insideZIndex: insidePriority,
-        insideZIndex: insidePriority,
+          insideLayer: Layer.spaceshipEntranceRamp,
-        insideLayer: insideLayer,
+        );
-      )..initialPosition = Vector2(0, 10);
+        await game.ensureAdd(layerSensor);
-
-      when(() => body.linearVelocity).thenReturn(Vector2(0, 1));
-
-      sensor.beginContact(ball, _MockContact());
-      verify(() => ball.layer = insideLayer).called(1);
-      verify(() => ball.zIndex = insidePriority).called(1);
-
-      when(() => ball.layer).thenReturn(insideLayer);
 
-      sensor.beginContact(ball, _MockContact());
+        expect(
-      verify(() => ball.layer = Layer.board);
+          layerSensor.children.whereType<LayerFilteringBehavior>().length,
-      verify(() => ball.zIndex = ZIndexes.ballOnBoard).called(1);
+          equals(1),
-    });
+        );
+      },
+    );
   });
 }