test: coverage for multipliers

test/game/components/controlled_multiplier_test.dart

@@ -0,0 +1,106 @@
+// ignore_for_file: cascade_invocations
+
+import 'package:flame_test/flame_test.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:pinball/game/game.dart';
+import 'package:pinball_components/pinball_components.dart';
+
+import '../../helpers/helpers.dart';
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+  final assets = [
+    Assets.images.multiplier.x2.active.keyName,
+    Assets.images.multiplier.x2.inactive.keyName,
+    Assets.images.multiplier.x3.active.keyName,
+    Assets.images.multiplier.x3.inactive.keyName,
+    Assets.images.multiplier.x4.active.keyName,
+    Assets.images.multiplier.x4.inactive.keyName,
+    Assets.images.multiplier.x5.active.keyName,
+    Assets.images.multiplier.x5.inactive.keyName,
+    Assets.images.multiplier.x6.active.keyName,
+    Assets.images.multiplier.x6.inactive.keyName,
+  ];
+  final flameTester = FlameTester(() => EmptyPinballTestGame(assets));
+
+  group('MultipliersGroup', () {
+    flameTester.test(
+      'loads correctly',
+      (game) async {
+        final multipliersGroup = MultipliersGroup();
+        await game.ensureAdd(multipliersGroup);
+
+        expect(game.contains(multipliersGroup), isTrue);
+      },
+    );
+
+    group('loads', () {
+      flameTester.test(
+        'five Multiplier',
+        (game) async {
+          final multipliersGroup = MultipliersGroup();
+          await game.ensureAdd(multipliersGroup);
+
+          expect(
+            multipliersGroup.descendants().whereType<Multiplier>().length,
+            equals(5),
+          );
+        },
+      );
+    });
+  });
+  group('MultipliersController', () {
+    group('controller', () {
+      // TODO(ruimiguel): change these tests to check multiplier change.
+      group('listenWhen', () {
+        flameTester.test(
+          'listens when score has changed',
+          (game) async {
+            const previous = GameState.initial();
+            final state = previous.copyWith(score: 100);
+
+            final multipliersGroup = MultipliersGroup();
+            await game.ensureAdd(multipliersGroup);
+
+            expect(
+              multipliersGroup.controller.listenWhen(previous, state),
+              isTrue,
+            );
+          },
+        );
+
+        flameTester.test(
+          "doesn't listen when score is the same",
+          (game) async {
+            const previous = GameState.initial();
+
+            final multipliersGroup = MultipliersGroup();
+            await game.ensureAdd(multipliersGroup);
+
+            expect(
+              multipliersGroup.controller.listenWhen(previous, previous),
+              isFalse,
+            );
+          },
+        );
+      });
+
+      group(
+        'onNewState',
+        () {
+          flameTester.test(
+            'spawns a ball',
+            (game) async {
+              final state = GameState.initial().copyWith(score: 100);
+
+              final multipliersGroup = MultipliersGroup();
+              await game.ensureAdd(multipliersGroup);
+
+              multipliersGroup.controller.onNewState(state);
+            },
+          );
+        },
+      );
+    });
+  });
+}