Different behavior when listening to streams (from drift) using StreamProvider vs StreamBuilder

[AhmedLSayed9]

Note: I couldn't re-produce the issue using raw streams, so you need to add the following dependencies in addition to Riverpod:

dependencies:
  drift: ^2.21.0
  drift_flutter: ^0.1.0
dev_dependencies:
  build_runner:
  drift_dev: ^2.21.0

The example is very simply:

import 'package:drift/drift.dart';
import 'package:drift_flutter/drift_flutter.dart';
import 'package:flutter/material.dart' hide Table;
import 'package:hooks_riverpod/hooks_riverpod.dart';

part 'main.g.dart';

class TodoItems extends Table {
  IntColumn get id => integer().autoIncrement()();
}

@DriftDatabase(tables: [TodoItems])
class AppDatabase extends _$AppDatabase {
  AppDatabase() : super(_openConnection());

  @override
  int get schemaVersion => 1;

  static QueryExecutor _openConnection() => driftDatabase(name: 'my_database');
}

final database = AppDatabase();

final todoStreamProvider = StreamProvider.autoDispose<List<int>>((ref) {
  return todoStream();
});

Stream<List<int>> todoStream() {
  return database.managers.todoItems.watch().map((value) {
    print('map Called with $value');
    return [];
  });
}

void main() async {
  runApp(const ProviderScope(child: MyApp()));
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: HomePage(),
    );
  }
}

class HomePage extends StatefulWidget {
  const HomePage({super.key});

  @override
  HomePageState createState() => HomePageState();
}

class HomePageState extends State<HomePage> {
  // TODO: uncomment this and use StreamBuilder instead of stream provider.
  //final stream = todoStream();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('CombineLatest2 Example')),
      body: Center(
        child: Consumer(
          builder: (context, ref, child) {
            ref.watch(todoStreamProvider);
            return const SizedBox();
          },
        ),
        /* child: StreamBuilder(
          stream: stream,
          builder: (context, snapshot) {
            return const SizedBox();
          },
        ), */
      ),
    );
  }
}

Steps:

1. Run the example as is (after running build runner for the generated code).
2. Notice the print statement print('map Called with $value'); prints twice.
3. Uncomment the line final stream = todoStream(); and the StreamBuilder code, and comment the Consumer code.
4. Re-run the example.
5. Notice the print statement print('map Called with $value'); prints once.

[rrousselGit]

I don't the time to investigate third-party packages. If this is important for you, I'd suggest looking into the issue yourself :)

[AhmedLSayed9]

I don't the time to investigate third-party packages. If this is important for you, I'd suggest looking into the issue yourself :)

I'm not sure if it's related to Riverpod or Drift (or not an issue after all), but I've leaned towards Riverpod as the same stream works fine with StreamBuilder. I'll try to dig into this more anyway.

[AhmedLSayed9]

Note to myself:
Manually listening to the stream:

final todoStreamProvider = StreamProvider.autoDispose<List<int>>((ref) {
  final controller = StreamController<List<int>>();
  todoStream().listen((v) => controller.add(v));
  ref.onDispose(() => controller.close());
  return controller.stream;
});

instead of returning the stream directly and let riverpod internally handle the listening:

final todoStreamProvider = StreamProvider.autoDispose<List<int>>((ref) {
  return todoStream();
});

works as expected similar to StreamBuilder