line != 'asynchronous gap' thrown when read provider with a dependency inside Notifier build. about riverpod

[rrousselGit]

For the same reason why podB specifies dependencies: [podA]

When podA is scoped, we want also to scope all of its dependents (podB).
That logic is recursive. Now that podB is scoped, we want also to scope all of its dependents (notipod).

The whole tree of dependents and transitive dependents relying on a scoped provider need to specify dependencies.

You should see an assert telling you you're missing a dependencies. And riverpod_lint should show a warning + quick fix too (although only if you were using codegen)

[rrousselGit]

Duplicate of #1874

[eli1stark]

@rrousselGit

I added the code to the main:

FlutterError.demangleStackTrace = (stack) {
  if (stack is Trace) return stack.vmTrace;
  if (stack is Chain) return stack.toTrace().vmTrace;
  return stack;
};

But this issue was more about why notipod is crashing.

I have this error now, which is more clear with demangleStackTrace but still remains an error.

Error

#1527   _LinkedHashMapMixin.putIfAbsent (dart:collection-patch/compact_hash.dart:535:23)
#1528   ConsumerStatefulElement.watch
consumer.dart:553
#1529   Home.build
main_development.dart:74
#1530   _ConsumerState.build
consumer.dart:479
#1531   StatefulElement.build
framework.dart:5198
#1532   ConsumerStatefulElement.build
consumer.dart:542
#1533   ComponentElement.performRebuild
framework.dart:5086
#1534   StatefulElement.performRebuild
framework.dart:5251
#1535   Element.rebuild
framework.dart:4805
#1536   ComponentElement._firstBuild
framework.dart:5068
#1537   StatefulElement._firstBuild
framework.dart:5242
#1538   ComponentElement.mount
framework.dart:5062
...     Normal element mounting (24 frames)
#1562   Element.inflateWidget
framework.dart:3971
#1563   MultiChildRenderObjectElement.inflateWidget
framework.dart:6570
#1564   MultiChildRenderObjectElement.mount
framework.dart:6582
...     Normal element mounting (178 frames)
#1742   Element.inflateWidget
framework.dart:3971
#1743   MultiChildRenderObjectElement.inflateWidget
framework.dart:6570
#1744   MultiChildRenderObjectElement.mount
framework.dart:6582
...     Normal element mounting (94 frames)
#1838   _UncontrolledProviderScopeElement.mount
framework.dart:309
...     Normal element mounting (399 frames)
#2237   _UncontrolledProviderScopeElement.mount
framework.dart:309
...     Normal element mounting (35 frames)
#2272   Element.inflateWidget
framework.dart:3971
#2273   Element.updateChild
framework.dart:3708
#2274   RenderObjectToWidgetElement._rebuild
binding.dart:1240
#2275   RenderObjectToWidgetElement.mount
binding.dart:1209
#2276   RenderObjectToWidgetAdapter.attachToRenderTree.<anonymous closure>
binding.dart:1156
#2277   BuildOwner.buildScope
framework.dart:2720
#2278   RenderObjectToWidgetAdapter.attachToRenderTree
binding.dart:1155
#2279   WidgetsBinding.attachRootWidget
binding.dart:988
#2280   WidgetsBinding.scheduleAttachRootWidget.<anonymous closure>
binding.dart:968
#2284   _RawReceivePort._handleMessage (dart:isolate-patch/isolate_patch.dart:189:12)
#2285   podA.<anonymous closure>
main_development.dart:26
#2286   ProviderElementBase.watch
element.dart:713
#2287   podB.<anonymous closure>
main_development.dart:32
#2288   ProviderElementBase.read
element.dart:690
#2289   MyNotifier.build
main_development.dart:42
#2290   ProviderContainer.listen
container.dart:285
#2291   ConsumerStatefulElement.watch.<anonymous closure>
consumer.dart:560
#2292   _LinkedHashMapMixin.putIfAbsent (dart:collection-patch/compact_hash.dart:535:23)
#2293   ConsumerStatefulElement.watch
consumer.dart:553
#2294   Home.build
main_development.dart:74
#2295   _ConsumerState.build
consumer.dart:479
#2296   StatefulElement.build
framework.dart:5198
#2297   ConsumerStatefulElement.build
consumer.dart:542
#2298   ComponentElement.performRebuild
framework.dart:5086
#2299   StatefulElement.performRebuild
framework.dart:5251
#2300   Element.rebuild
framework.dart:4805
#2301   ComponentElement._firstBuild
framework.dart:5068
#2302   StatefulElement._firstBuild
framework.dart:5242
#2303   ComponentElement.mount
framework.dart:5062
...     Normal element mounting (24 frames)
#2327   Element.inflateWidget
framework.dart:3971
#2328   MultiChildRenderObjectElement.inflateWidget
framework.dart:6570
#2329   MultiChildRenderObjectElement.mount
framework.dart:6582
...     Normal element mounting (178 frames)
#2507   Element.inflateWidget
framework.dart:3971
#2508   MultiChildRenderObjectElement.inflateWidget
framework.dart:6570
#2509   MultiChildRenderObjectElement.mount
framework.dart:6582
...     Normal element mounting (94 frames)
#2603   _UncontrolledProviderScopeElement.mount
framework.dart:309
...     Normal element mounting (399 frames)
#3002   _UncontrolledProviderScopeElement.mount
framework.dart:309
...     Normal element mounting (35 frames)
#3037   Element.inflateWidget
framework.dart:3971
#3038   Element.updateChild
framework.dart:3708
#3039   RenderObjectToWidgetElement._rebuild
binding.dart:1240
#3040   RenderObjectToWidgetElement.mount
binding.dart:1209
#3041   RenderObjectToWidgetAdapter.attachToRenderTree.<anonymous closure>
binding.dart:1156
#3042   BuildOwner.buildScope
framework.dart:2720
#3043   RenderObjectToWidgetAdapter.attachToRenderTree
binding.dart:1155
#3044   WidgetsBinding.attachRootWidget
binding.dart:988
#3045   WidgetsBinding.scheduleAttachRootWidget.<anonymous closure>
binding.dart:968
#3049   _RawReceivePort._handleMessage (dart:isolate-patch/isolate_patch.dart:189:12)
(elided 12 frames from class _Timer and dart:async-patch)
════════════════════════════════════════════════════════════════════════════════

I think I can rephrase the issue now to: "Override with value doesn't work properly when accessed from Notifier".

Value of podA in my example is defined for Widget.build but for Notifier.build is still undefined.

[rrousselGit]

Your notipod did not specify dependencies on podB

[eli1stark]

Hmm, yes, that works, thank you.

But if I create

final podC = Provider<int>((ref) => 2);

And use it like so:

class MyNotifier extends Notifier<int> {
  @override
  int build() => ref.read(podC) + 1;
}

notipod doesn't require any dependencies to work properly, why is so?

[eli1stark]

Thank you, Remi, now it's clear.