Widget test failing when passing already created bloc instance to provider - flutter

Question

I'm passing the CartBloc instance to the BlocProvider. But the test is failing as the ListView widget is not found.
Below is the test code.
void main() {
late MockCartRepository cartRepository;
late MockSharedPreferenceService sharedPreferenceService;
late AuthBloc authBloc;
late MockUserRepository userRepository;
late CartData cartData;
late CartBloc cartBloc;
setUp(() {
cartData = CartData.fromJson(guestCartData);
cartRepository = MockCartRepository();
sharedPreferenceService = MockSharedPreferenceService();
userRepository = MockUserRepository();
authBloc = AuthBloc(
service: sharedPreferenceService,
userRepository: userRepository,
);
cartBloc = CartBloc(
cartRepository: cartRepository,
sharedPreferenceService: sharedPreferenceService,
authBloc: authBloc,
);
});
_pumpTestWidgetWithEvent(WidgetTester tester, CartEvent event) {
return MaterialApp(
home: BlocProvider(
create: (_) => cartBloc..add(event),
child: const CartView(),
),
);
}
group('Testing cart view', () {
testWidgets(
'Adding item to cart',
(WidgetTester tester) async {
when(cartBloc.cartRepository.addToCart(
cartId: cartData.id!,
quantity: 1,
variantId: cartData.lineItems!.physicalItems!.first.variantId!,
productId: cartData.lineItems!.physicalItems!.first.productId!,
)).thenAnswer((_) async => cartData);
when(sharedPreferenceService.setString('cartId', cartData.id!))
.thenAnswer((_) async => true);
await tester.pumpWidget(
_pumpTestWidgetWithEvent(
tester,
AddToCartEvent(
cartId: cartData.id!,
quantity: 1,
variantId: cartData.lineItems!.physicalItems!.first.variantId!,
productId: cartData.lineItems!.physicalItems!.first.productId!,
),
),
);
await tester.pumpAndSettle();
expect(find.text('Cart'), findsOneWidget);
expect(find.byType(ListView), findsOneWidget);
},
);
});
}
The test passes when I pass a new instance of cart bloc as shown below.
_pumpTestWidgetWithEvent(WidgetTester tester, CartEvent event) {
return MaterialApp(
home: BlocProvider(
create: (_) => CartBloc(
cartRepository: cartRepository,
sharedPreferenceService: sharedPreferenceService,
authBloc: authBloc,
)..add(event),
child: const CartView(),
),
);
}
Why is this happening?
I've also tried using BlocProvider.value and passing cartBloc as value. But this also failing.