How to handle ref invalidation during async gaps?

[btrautmann]

Hello 👋

I'm running into an issue that I've seen mentioned only a couple times, where I receive the following error between async gaps in Providers, specifically those that are awaiting another Provider's Future or Stream.

[ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: 'package:riverpod/src/framework/element.dart': Failed assertion: line 673 pos 7: '!_didChangeDependency': Cannot use ref functions after the dependency of a provider changed but before the provider rebuilt

I understand what the error is telling me, and you highlight that in your comment here, but this happens in cases where there are no awaits in the Provider "chain" other than those awaiting other Providers.

One such case is below:

// Both categoryGroups and tracker await FutureProviders that await StreamProviders that yield models from an `Isar` database
final categoryGroups = await ref.watch(categoryGroupsProvider.future);
final tracker = await ref.watch(spendTrackerProvider(trackerId).future);
final incomeFilter = ref.watch(incomeFilterProvider); // Error occurs here
final groupByDate = ref.watch(groupByDateProvider);

If, during these async gaps, the ref is being invalidated, how am I supposed to guard against that? I don't see an API similar to mounted for StateNotifier.

As a follow-up, am I abusing ref.watch(provider.future)? Is this an anti-pattern, or is this a pretty expected use case? It seems that these async gaps would be pretty commonplace in Provider code utilizing Future/StreamProvider, but I'm unsure if I'm just doing something dumb.

Thanks for any help!

[rrousselGit]

If, during these async gaps, the ref is being invalidated, how am I supposed to guard against that? I don't see an API similar to mounted for StateNotifier.

Use ref.onDispose to detect if the provider was disposed during an await. That generally should help