autoDispose the addToCartControllerProvider + tests

ecommerce_app/lib/src/features/cart/domain/item.dart

@@ -8,4 +8,16 @@ class Item {
   });
   final ProductID productId;
   final int quantity;
+
+  @override
+  bool operator ==(Object other) {
+    if (identical(this, other)) return true;
+
+    return other is Item &&
+        other.productId == productId &&
+        other.quantity == quantity;
+  }
+
+  @override
+  int get hashCode => productId.hashCode ^ quantity.hashCode;
 }

ecommerce_app/lib/src/features/cart/presentation/add_to_cart/add_to_cart_controller.dart

@@ -23,9 +23,9 @@ class AddToCartController extends StateNotifier<AsyncValue<int>> {
   }
 }
 
-// TODO: Should this use autoDispose?
 final addToCartControllerProvider =
-    StateNotifierProvider<AddToCartController, AsyncValue<int>>((ref) {
+    StateNotifierProvider.autoDispose<AddToCartController, AsyncValue<int>>(
+        (ref) {
   return AddToCartController(
     cartService: ref.watch(cartServiceProvider),
   );

ecommerce_app/test/src/features/cart/presentation/add_to_cart/add_to_cart_controller_test.dart

@@ -0,0 +1,74 @@
+import 'package:ecommerce_app/src/features/cart/domain/item.dart';
+import 'package:ecommerce_app/src/features/cart/presentation/add_to_cart/add_to_cart_controller.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mocktail/mocktail.dart';
+
+import '../../../../mocks.dart';
+
+void main() {
+  const productId = '1';
+  group('addItem', () {
+    test('item added with quantity = 2, success', () async {
+      // setup
+      const quantity = 2;
+      const item = Item(productId: productId, quantity: quantity);
+      final cartService = MockCartService();
+      when(() => cartService.addItem(item)).thenAnswer(
+        (_) => Future.value(null),
+      );
+      // run & verify
+      final controller = AddToCartController(cartService: cartService);
+      expect(
+        controller.state,
+        const AsyncData(1),
+      );
+      controller.updateQuantity(quantity);
+      expect(
+        controller.state,
+        const AsyncData(2),
+      );
+      // * if desired, use expectLater and emitsInOrder here to check that
+      // * addItems emits two values
+      await controller.addItem(productId);
+      verify(() => cartService.addItem(item)).called(1);
+      // check that quantity goes back to 1 after adding an item
+      expect(
+        controller.state,
+        const AsyncData(1),
+      );
+    });
+
+    test('item added with quantity = 2, failure', () async {
+      const quantity = 2;
+      const item = Item(productId: productId, quantity: quantity);
+      final cartService = MockCartService();
+      when(() => cartService.addItem(item))
+          .thenThrow((_) => Exception('Connection failed'));
+      final controller = AddToCartController(cartService: cartService);
+      expect(
+        controller.state,
+        const AsyncData(1),
+      );
+      controller.updateQuantity(quantity);
+      expect(
+        controller.state,
+        const AsyncData(2),
+      );
+      // * if desired, use expectLater and emitsInOrder here to check that
+      // * addItems emits two values
+      await controller.addItem(productId);
+      verify(() => cartService.addItem(item)).called(1);
+      // check that quantity goes back to 1 after adding an item
+      expect(
+        controller.state,
+        predicate<AsyncValue<int>>(
+          (value) {
+            expect(value.hasError, true);
+            return true;
+          },
+        ),
+      );
+    });
+  });
+}

ecommerce_app/test/src/mocks.dart

@@ -1,4 +1,5 @@
 import 'package:ecommerce_app/src/features/authentication/data/fake_auth_repository.dart';
+import 'package:ecommerce_app/src/features/cart/application/cart_service.dart';
 import 'package:ecommerce_app/src/features/cart/data/local/local_cart_repository.dart';
 import 'package:ecommerce_app/src/features/cart/data/remote/remote_cart_repository.dart';
 import 'package:mocktail/mocktail.dart';
@@ -8,3 +9,5 @@ class MockAuthRepository extends Mock implements FakeAuthRepository {}
 class MockRemoteCartRepository extends Mock implements RemoteCartRepository {}
 
 class MockLocalCartRepository extends Mock implements LocalCartRepository {}
+
+class MockCartService extends Mock implements CartService {}