test: transition mixin test

test/home/widgets/transition_screen_mixin_test.dart

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+import 'dart:async';
+
+import 'package:bloc_test/bloc_test.dart';
+import 'package:dash_ai_search/home/home.dart';
+import 'package:dash_ai_search/home/widgets/transition_screen_mixin.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mocktail/mocktail.dart';
+
+import '../../helpers/helpers.dart';
+
+class _MockHomeBloc extends MockBloc<HomeEvent, HomeState>
+    implements HomeBloc {}
+
+class _MockAnimationController extends Mock implements AnimationController {}
+
+class SampleWidget extends StatefulWidget {
+  const SampleWidget({
+    required this.mockedEnterTransitionController,
+    required this.mockedExitTransitionController,
+    super.key,
+  });
+
+  final AnimationController mockedEnterTransitionController;
+  final AnimationController mockedExitTransitionController;
+
+  @override
+  State<SampleWidget> createState() => _SampleWidgetState();
+}
+
+class _SampleWidgetState extends State<SampleWidget>
+    with SingleTickerProviderStateMixin, TransitionScreenMixin {
+  @override
+  List<Status> get forwardEnterStatuses => [Status.welcome];
+
+  @override
+  List<Status> get forwardExitStatuses => [Status.welcomeToAskQuestion];
+
+  @override
+  List<Status> get backEnterStatuses => [Status.askQuestion];
+
+  @override
+  List<Status> get backExitStatuses => [Status.askQuestionToThinking];
+
+  @override
+  void initializeTransitionController() {
+    enterTransitionController = widget.mockedEnterTransitionController;
+    exitTransitionController = widget.mockedExitTransitionController;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Container();
+  }
+}
+
+void main() {
+  group('TransitionScreenMixin', () {
+    late HomeBloc homeBloc;
+    late AnimationController enterAnimationController;
+    late AnimationController exitAnimationController;
+
+    setUp(() {
+      homeBloc = _MockHomeBloc();
+      when(() => homeBloc.state).thenReturn(HomeState());
+
+      enterAnimationController = _MockAnimationController();
+      when(() => enterAnimationController.forward())
+          .thenAnswer((invocation) => TickerFuture.complete());
+      when(() => enterAnimationController.reverse())
+          .thenAnswer((invocation) => TickerFuture.complete());
+      when(() => enterAnimationController.addStatusListener(any()))
+          .thenAnswer((invocation) {});
+      when(() => enterAnimationController.dispose())
+          .thenAnswer((invocation) {});
+
+      exitAnimationController = _MockAnimationController();
+      when(() => exitAnimationController.forward())
+          .thenAnswer((invocation) => TickerFuture.complete());
+      when(() => exitAnimationController.reverse())
+          .thenAnswer((invocation) => TickerFuture.complete());
+      when(() => exitAnimationController.addStatusListener(any()))
+          .thenAnswer((invocation) {});
+      when(() => exitAnimationController.dispose()).thenAnswer((invocation) {});
+    });
+
+    testWidgets(
+        'calls enterAnimationController forward '
+        'when status is in forwardEnterStatuses', (tester) async {
+      final streamController = StreamController<HomeState>();
+      whenListen(
+        homeBloc,
+        streamController.stream,
+        initialState: HomeState(),
+      );
+
+      await tester.pumpApp(
+        BlocProvider.value(
+          value: homeBloc,
+          child: SampleWidget(
+            mockedEnterTransitionController: enterAnimationController,
+            mockedExitTransitionController: exitAnimationController,
+          ),
+        ),
+      );
+
+      streamController.add(const HomeState());
+      verify(() => enterAnimationController.forward()).called(1);
+    });
+
+    testWidgets(
+        'calls exitTransitionController forward '
+        'when status is in forwardExitStatuses', (tester) async {
+      final streamController = StreamController<HomeState>();
+      whenListen(
+        homeBloc,
+        streamController.stream,
+        initialState: HomeState(),
+      );
+
+      await tester.pumpApp(
+        BlocProvider.value(
+          value: homeBloc,
+          child: SampleWidget(
+            mockedEnterTransitionController: enterAnimationController,
+            mockedExitTransitionController: exitAnimationController,
+          ),
+        ),
+      );
+
+      streamController
+          .add(const HomeState(status: Status.welcomeToAskQuestion));
+      verify(() => exitAnimationController.forward()).called(1);
+    });
+
+    testWidgets(
+        'calls exitAnimationController reverse '
+        'when status is in backEnterStatuses', (tester) async {
+      final streamController = StreamController<HomeState>();
+      whenListen(
+        homeBloc,
+        streamController.stream,
+        initialState: HomeState(),
+      );
+
+      await tester.pumpApp(
+        BlocProvider.value(
+          value: homeBloc,
+          child: SampleWidget(
+            mockedEnterTransitionController: enterAnimationController,
+            mockedExitTransitionController: exitAnimationController,
+          ),
+        ),
+      );
+
+      streamController.add(const HomeState(status: Status.askQuestion));
+      verify(() => exitAnimationController.reverse()).called(1);
+    });
+
+    testWidgets(
+        'calls enterAnimationController reverse '
+        'when status is in backExitStatuses', (tester) async {
+      final streamController = StreamController<HomeState>();
+      whenListen(
+        homeBloc,
+        streamController.stream,
+        initialState: HomeState(),
+      );
+
+      await tester.pumpApp(
+        BlocProvider.value(
+          value: homeBloc,
+          child: SampleWidget(
+            mockedEnterTransitionController: enterAnimationController,
+            mockedExitTransitionController: exitAnimationController,
+          ),
+        ),
+      );
+
+      streamController
+          .add(const HomeState(status: Status.askQuestionToThinking));
+      verify(() => enterAnimationController.reverse()).called(1);
+    });
+  });
+}