Workaround memory leak in bloc

app/lib/bloc_util.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:provider/single_child_widget.dart';
@@ -58,3 +60,42 @@ extension BlocExtension<E, S> on Bloc<E, S> {
     }
   }
 }
+
+class _BlocForEachObj {
+  const _BlocForEachObj(this.subscription, this.completer);
+
+  final StreamSubscription subscription;
+  final Completer completer;
+}
+
+mixin BlocForEachMixin<E, S> implements Bloc<E, S> {
+  @override
+  Future<void> close() async {
+    for (final e in _forEaches) {
+      unawaited(e.subscription.cancel());
+      e.completer.complete();
+    }
+  }
+
+  // The original emit.forEach is causing the internal eventController in Bloc
+  // to deadlock when closing, use this instead
+  Future<void> forEach<T>(
+    Emitter<S> emit,
+    Stream<T> stream, {
+    required S Function(T data) onData,
+    S Function(Object error, StackTrace stackTrace)? onError,
+  }) async {
+    final completer = Completer();
+    final subscription = stream.listen((event) {
+      emit(onData(event));
+    }, onError: (e, stackTrace) {
+      if (onError != null) {
+        emit(onError(e, stackTrace));
+      }
+    });
+    _forEaches.add(_BlocForEachObj(subscription, completer));
+    return completer.future;
+  }
+
+  final _forEaches = <_BlocForEachObj>[];
+}

app/lib/widget/archive_browser/bloc.dart

@@ -1,7 +1,8 @@
 part of '../archive_browser.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.account,
     required this.filesController,
@@ -58,7 +59,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onLoad(_LoadItems ev, Emitter<_State> emit) {
     _log.info(ev);
     unawaited(filesController.queryByArchived());
-    return emit.forEach<FilesStreamEvent>(
+    return forEach(
+      emit,
       filesController.stream,
       onData: (data) => state.copyWith(
         files: data.data,

app/lib/widget/collection_browser/bloc.dart

@@ -1,7 +1,8 @@
 part of '../collection_browser.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required DiContainer container,
     required this.account,
@@ -121,7 +122,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onLoad(_LoadItems ev, Emitter<_State> emit) async {
     _log.info(ev);
     await Future.wait([
-      emit.forEach<CollectionItemStreamData>(
+      forEach(
+        emit,
         itemsController.stream,
         onData: (data) => state.copyWith(
           items: _filterItems(data.items, state.itemsWhitelist),
@@ -136,7 +138,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           );
         },
       ),
-      emit.forEach<FilesStreamEvent>(
+      forEach(
+        emit,
         filesController.stream,
         onData: (data) {
           final whitelist = HashSet.of(data.dataMap.keys);

app/lib/widget/collection_picker/bloc.dart

@@ -1,7 +1,8 @@
 part of '../collection_picker.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.account,
     required this.controller,
@@ -31,7 +32,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
 
   Future<void> _onLoad(_LoadCollections ev, Emitter<_State> emit) async {
     _log.info(ev);
-    return emit.forEach<CollectionStreamEvent>(
+    return forEach(
+      emit,
       controller.stream,
       onData: (data) => state.copyWith(
         collections: data.data.map((e) => e.collection).toList(),

app/lib/widget/home_collections/bloc.dart

@@ -1,7 +1,8 @@
 part of '../home_collections.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.account,
     required this.controller,
@@ -69,7 +70,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
 
   Future<void> _onLoad(_LoadCollections ev, Emitter<_State> emit) async {
     _log.info(ev);
-    return emit.forEach<CollectionStreamEvent>(
+    return forEach(
+      emit,
       controller.stream,
       onData: (data) => state.copyWith(
         collections: data.data.map((d) => d.collection).toList(),

app/lib/widget/home_photos/bloc.dart

@@ -1,7 +1,8 @@
 part of '../home_photos2.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc(
     this._c, {
     required this.account,
@@ -138,7 +139,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onLoad(_LoadItems ev, Emitter<_State> emit) async {
     _log.info(ev);
     await Future.wait([
-      emit.forEach<FilesSummaryStreamEvent>(
+      forEach(
+        emit,
         filesController.summaryStream,
         onData: (data) {
           if (data.summary.items.isEmpty && _isInitialLoad) {
@@ -157,7 +159,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           );
         },
       ),
-      emit.forEach<TimelineStreamEvent>(
+      forEach(
+        emit,
         filesController.timelineStream,
         onData: (data) {
           if (!data.isDummy && _isInitialLoad) {

app/lib/widget/people_browser/bloc.dart

@@ -1,7 +1,8 @@
 part of '../people_browser.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.account,
     required this.personsController,
@@ -16,7 +17,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
 
   Future<void> _onLoad(_LoadPersons ev, Emitter<_State> emit) {
     _log.info(ev);
-    return emit.forEach<PersonStreamEvent>(
+    return forEach(
+      emit,
       personsController.stream,
       onData: (data) => state.copyWith(
         persons: data.data,

app/lib/widget/places_browser/bloc.dart

@@ -1,7 +1,8 @@
 part of '../places_browser.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.account,
     required this.placesController,
@@ -16,7 +17,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
 
   Future<void> _onLoad(_LoadPlaces ev, Emitter<_State> emit) {
     _log.info(ev);
-    return emit.forEach<PlaceStreamEvent>(
+    return forEach(
+      emit,
       placesController.stream,
       onData: (data) => state.copyWith(
         places: data.data,

app/lib/widget/search_landing/bloc.dart

@@ -1,7 +1,8 @@
 part of '../search_landing.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.account,
     required this.personsController,
@@ -18,7 +19,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
 
   Future<void> _onLoadPersons(_LoadPersons ev, Emitter<_State> emit) {
     _log.info(ev);
-    return emit.forEach<PersonStreamEvent>(
+    return forEach(
+      emit,
       personsController.stream,
       onData: (data) => state.copyWith(
         persons: data.data,
@@ -54,7 +56,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
 
   Future<void> _onLoadPlaces(_LoadPlaces ev, Emitter<_State> emit) {
     _log.info(ev);
-    return emit.forEach<PlaceStreamEvent>(
+    return forEach(
+      emit,
       placesController.stream,
       onData: (data) => state.copyWith(
         places: data.data,

app/lib/widget/settings/collection/bloc.dart

@@ -1,7 +1,8 @@
 part of '../collection_settings.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.prefController,
   }) : super(_State(
@@ -16,7 +17,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
 
   Future<void> _onInit(_Init ev, Emitter<_State> emit) async {
     _log.info(ev);
-    return emit.forEach<bool>(
+    return forEach(
+      emit,
       prefController.isAlbumBrowserShowDateChange,
       onData: (data) => state.copyWith(isBrowserShowDate: data),
       onError: (e, stackTrace) {

app/lib/widget/settings/enhancement/bloc.dart

@@ -1,7 +1,8 @@
 part of '../enhancement_settings.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.prefController,
   }) : super(_State(
@@ -20,7 +21,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onInit(_Init ev, Emitter<_State> emit) async {
     _log.info(ev);
     await Future.wait([
-      emit.forEach<bool>(
+      forEach(
+        emit,
         prefController.isSaveEditResultToServerChange,
         onData: (data) => state.copyWith(isSaveEditResultToServer: data),
         onError: (e, stackTrace) {
@@ -28,7 +30,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<SizeInt>(
+      forEach(
+        emit,
         prefController.enhanceMaxSizeChange,
         onData: (data) => state.copyWith(maxSize: data),
         onError: (e, stackTrace) {

app/lib/widget/settings/language/bloc.dart

@@ -1,7 +1,8 @@
 part of '../language_settings.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.prefController,
   }) : super(_State.init(
@@ -30,7 +31,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
 
   Future<void> _onInit(_Init ev, Emitter<_State> emit) {
     _log.info(ev);
-    return emit.forEach<language_util.AppLanguage>(
+    return forEach(
+      emit,
       prefController.languageChange,
       onData: (data) => state.copyWith(selected: data),
       onError: (e, stackTrace) {

app/lib/widget/settings/metadata/bloc.dart

@@ -1,7 +1,8 @@
 part of '../metadata_settings.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.prefController,
   }) : super(_State(
@@ -19,7 +20,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onInit(_Init ev, Emitter<_State> emit) async {
     _log.info(ev);
     await Future.wait([
-      emit.forEach<bool>(
+      forEach(
+        emit,
         prefController.isEnableExifChange,
         onData: (data) => state.copyWith(isEnable: data),
         onError: (e, stackTrace) {
@@ -27,7 +29,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<bool>(
+      forEach(
+        emit,
         prefController.shouldProcessExifWifiOnlyChange,
         onData: (data) => state.copyWith(isWifiOnly: data),
         onError: (e, stackTrace) {

app/lib/widget/settings/misc/bloc.dart

@@ -1,7 +1,8 @@
 part of '../misc_settings.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.prefController,
     required this.securePrefController,
@@ -19,7 +20,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onInit(_Init ev, Emitter<_State> emit) async {
     _log.info(ev);
     await Future.wait([
-      emit.forEach<bool>(
+      forEach(
+        emit,
         prefController.isDoubleTapExitChange,
         onData: (data) => state.copyWith(isDoubleTapExit: data),
         onError: (e, stackTrace) {
@@ -27,7 +29,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<ProtectedPageAuthType?>(
+      forEach(
+        emit,
         securePrefController.protectedPageAuthTypeChange,
         onData: (data) => state.copyWith(appLockType: data),
         onError: (e, stackTrace) {

app/lib/widget/settings/photos/bloc.dart

@@ -1,7 +1,8 @@
 part of '../photos_settings.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.prefController,
     required this.accountPrefController,
@@ -20,7 +21,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onInit(_Init ev, Emitter<_State> emit) async {
     _log.info(ev);
     await Future.wait([
-      emit.forEach<bool>(
+      forEach(
+        emit,
         accountPrefController.isEnableMemoryAlbumChange,
         onData: (data) => state.copyWith(isEnableMemories: data),
         onError: (e, stackTrace) {
@@ -28,7 +30,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<int>(
+      forEach(
+        emit,
         prefController.memoriesRangeChange,
         onData: (data) => state.copyWith(memoriesRange: data),
         onError: (e, stackTrace) {

app/lib/widget/settings/theme/bloc.dart

@@ -1,7 +1,8 @@
 part of '../theme_settings.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.prefController,
   }) : super(_State(
@@ -22,7 +23,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onInit(_Init ev, Emitter<_State> emit) async {
     _log.info(ev);
     await Future.wait([
-      emit.forEach<bool>(
+      forEach(
+        emit,
         prefController.isFollowSystemThemeChange,
         onData: (data) => state.copyWith(isFollowSystemTheme: data),
         onError: (e, stackTrace) {
@@ -30,7 +32,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<bool>(
+      forEach(
+        emit,
         prefController.isUseBlackInDarkThemeChange,
         onData: (data) => state.copyWith(isUseBlackInDarkTheme: data),
         onError: (e, stackTrace) {
@@ -38,7 +41,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<Color?>(
+      forEach(
+        emit,
         prefController.seedColorChange,
         onData: (data) => state.copyWith(seedColor: data?.value),
         onError: (e, stackTrace) {
@@ -46,7 +50,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<Color?>(
+      forEach(
+        emit,
         prefController.secondarySeedColorChange,
         onData: (data) => state.copyWith(secondarySeedColor: data?.value),
         onError: (e, stackTrace) {

app/lib/widget/settings/viewer/bloc.dart

@@ -1,7 +1,8 @@
 part of '../viewer_settings.dart';
 
 @npLog
-class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+class _Bloc extends Bloc<_Event, _State>
+    with BlocLogger, BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.prefController,
   }) : super(_State(
@@ -21,7 +22,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
   Future<void> _onInit(_Init ev, Emitter<_State> emit) async {
     _log.info(ev);
     await Future.wait([
-      emit.forEach<int>(
+      forEach(
+        emit,
         prefController.viewerScreenBrightnessChange,
         onData: (data) => state.copyWith(screenBrightness: data),
         onError: (e, stackTrace) {
@@ -29,7 +31,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<bool>(
+      forEach(
+        emit,
         prefController.isViewerForceRotationChange,
         onData: (data) => state.copyWith(isForceRotation: data),
         onError: (e, stackTrace) {
@@ -37,7 +40,8 @@ class _Bloc extends Bloc<_Event, _State> with BlocLogger {
           return state.copyWith(error: ExceptionEvent(e, stackTrace));
         },
       ),
-      emit.forEach<GpsMapProvider>(
+      forEach(
+        emit,
         prefController.gpsMapProviderChange,
         onData: (data) => state.copyWith(gpsMapProvider: data),
         onError: (e, stackTrace) {

app/lib/widget/sharing_browser.dart

@@ -9,6 +9,7 @@ import 'package:kiwi/kiwi.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/account.dart';
 import 'package:nc_photos/app_localizations.dart';
+import 'package:nc_photos/bloc_util.dart';
 import 'package:nc_photos/controller/account_controller.dart';
 import 'package:nc_photos/controller/account_pref_controller.dart';
 import 'package:nc_photos/controller/sharings_controller.dart';

app/lib/widget/sharing_browser/bloc.dart

@@ -2,7 +2,7 @@ part of '../sharing_browser.dart';
 
 /// List shares to be shown in [SharingBrowser]
 @npLog
-class _Bloc extends Bloc<_Event, _State> {
+class _Bloc extends Bloc<_Event, _State> with BlocForEachMixin<_Event, _State> {
   _Bloc({
     required this.account,
     required this.accountPrefController,
@@ -21,7 +21,8 @@ class _Bloc extends Bloc<_Event, _State> {
           "[_onInit] Failed while _importPotentialSharedAlbum", e, stackTrace);
     }
     unawaited(sharingsController.reload());
-    return emit.forEach<SharingStreamEvent>(
+    return forEach(
+      emit,
       sharingsController.stream,
       onData: (data) => state.copyWith(
         items: data.data,