Update controller to avoid submitting the review if the data hasn't c…

…hanged

ecommerce_app/lib/src/features/reviews/presentation/leave_review_screen/leave_review_controller.dart

@@ -14,25 +14,33 @@ class LeaveReviewController extends StateNotifier<AsyncValue<void>> {
   final DateTime Function() currentDateBuilder;
 
   Future<void> submitReview({
+    Review? previousReview,
     required ProductID productId,
     required double rating,
     required String comment,
     required void Function() onSuccess,
   }) async {
-    final review = Review(
-      rating: rating,
-      comment: comment,
-      date: currentDateBuilder(),
-    );
-    state = const AsyncLoading();
-    final newState = await AsyncValue.guard(() =>
-        reviewsService.submitReview(productId: productId, review: review));
-    if (mounted) {
-      // * only set the state if the controller hasn't been disposed
-      state = newState;
-      if (state.hasError == false) {
-        onSuccess();
+    // * only submit if the rating is new or it has changed
+    if (previousReview == null ||
+        rating != previousReview.rating ||
+        comment != previousReview.comment) {
+      final review = Review(
+        rating: rating,
+        comment: comment,
+        date: currentDateBuilder(),
+      );
+      state = const AsyncLoading();
+      final newState = await AsyncValue.guard(() =>
+          reviewsService.submitReview(productId: productId, review: review));
+      if (mounted) {
+        // * only set the state if the controller hasn't been disposed
+        state = newState;
+        if (state.hasError == false) {
+          onSuccess();
+        }
       }
+    } else {
+      onSuccess();
     }
   }
 }

ecommerce_app/lib/src/features/reviews/presentation/leave_review_screen/leave_review_screen.dart

@@ -118,6 +118,7 @@ class _LeaveReviewFormState extends ConsumerState<LeaveReviewForm> {
               ? null
               : () =>
                   ref.read(leaveReviewControllerProvider.notifier).submitReview(
+                        previousReview: widget.review,
                         productId: widget.productId,
                         rating: _rating,
                         comment: _controller.text,

ecommerce_app/test/src/features/reviews/presentation/leave_review_screen/leave_review_controller_test.dart

@@ -0,0 +1,127 @@
+import 'package:ecommerce_app/src/features/reviews/domain/review.dart';
+import 'package:ecommerce_app/src/features/reviews/presentation/leave_review_screen/leave_review_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() {
+  final testDate = DateTime(2022, 7, 31);
+  const testRating = 5.0;
+  const testComment = 'love it!';
+  final testReview = Review(
+    rating: testRating,
+    comment: testComment,
+    date: testDate,
+  );
+  const testProductId = '1';
+
+  late MockReviewsService reviewsService;
+  setUp(() {
+    reviewsService = MockReviewsService();
+  });
+
+  group('submitReview', () {
+    test('success', () async {
+      // setup
+      when(() => reviewsService.submitReview(
+            productId: testProductId,
+            review: testReview,
+          )).thenAnswer((_) => Future.value());
+      final controller = LeaveReviewController(
+        reviewsService: reviewsService,
+        currentDateBuilder: () => testDate,
+      );
+      // run & verify
+      var didSucceed = false;
+      expectLater(
+        controller.stream,
+        emitsInOrder([
+          const AsyncLoading<void>(),
+          const AsyncData<void>(null),
+        ]),
+      );
+      await controller.submitReview(
+        previousReview: null,
+        rating: testRating,
+        comment: testComment,
+        productId: testProductId,
+        onSuccess: () => didSucceed = true,
+      );
+      verify(() => reviewsService.submitReview(
+            productId: testProductId,
+            review: testReview,
+          )).called(1);
+      expect(didSucceed, true);
+    });
+
+    test('failure', () async {
+      // setup
+      when(() => reviewsService.submitReview(
+            productId: testProductId,
+            review: testReview,
+          )).thenThrow(Exception('Connection failed'));
+      final controller = LeaveReviewController(
+        reviewsService: reviewsService,
+        currentDateBuilder: () => testDate,
+      );
+      // run & verify
+      var didSucceed = false;
+      expectLater(
+        controller.stream,
+        emitsInOrder([
+          const AsyncLoading<void>(),
+          predicate<AsyncValue<void>>(
+            (value) {
+              expect(value.hasError, true);
+              return true;
+            },
+          )
+        ]),
+      );
+      await controller.submitReview(
+        previousReview: null,
+        rating: testRating,
+        comment: testComment,
+        productId: testProductId,
+        onSuccess: () => didSucceed = true,
+      );
+      verify(() => reviewsService.submitReview(
+            productId: testProductId,
+            review: testReview,
+          )).called(1);
+      expect(didSucceed, false);
+    });
+
+    test('same data as before', () async {
+      // setup
+      when(() => reviewsService.submitReview(
+            productId: testProductId,
+            review: testReview,
+          )).thenThrow(Exception('Connection failed'));
+      final controller = LeaveReviewController(
+        reviewsService: reviewsService,
+        currentDateBuilder: () => testDate,
+      );
+      // run & verify
+      var didSucceed = false;
+      expectLater(
+        controller.stream,
+        emitsInOrder([]), // no state changes
+      );
+      await controller.submitReview(
+        previousReview: testReview,
+        rating: testRating,
+        comment: testComment,
+        productId: testProductId,
+        onSuccess: () => didSucceed = true,
+      );
+      verifyNever(() => reviewsService.submitReview(
+            productId: testProductId,
+            review: testReview,
+          ));
+      expect(didSucceed, true);
+    });
+  });
+}