rx_bloc_test

Description:

rx bloc test

rx_bloc_test #
A Flutter package with the goal to enable testing RxBlocs from the FlutterRxBloc package with ease.
rxBlocTest #
Testing a specific RxBloc state can be done easily with the rxBlocTest function. Besides a test description, it has two required parameters: build, which should return the testing RxBloc and state, which is a specific state inside the provided bloc.
Additionally, like in most cases, the state may return values which can be compared against other values. Here comes the expect parameter which takes a list of expected iterables and compares them with the ones from the state.
rxBlocTest<CounterBloc,int>(
'Emits [] when created',
build: () async => CounterBloc(),
state: (bloc) => bloc.states.count,
expect: [],
)
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There is an act parameter which is a callback executed after the bloc has been initialized. It should be used to add events to the block.
rxBlocTest<CounterBloc,int>(
'Incrementing value',
build: () async => CounterBloc(),
state: (bloc) => bloc.states.count,
act: (bloc) async => bloc.events.increment(),
expect: [1],
)
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If you want, you can skip a custom amount of values that are emitted by the state by using the skip parameter. If no value is provided the default value of 1 is used, which will skip the initial value of the bloc state. The initial value can be included by setting the skip parameter to 0.
There is also a wait parameter which will wait for a given Duration to pass. This is useful especially when working with async operations.
rxBlocTest<DetailsBloc,String>(
'Fetch third details data',
build: () async => DetailsBloc(),
state: (bloc) => bloc.states.details,
act: (bloc) async => bloc.events.fetch(),
wait: Duration(milliseconds:100),
skip: 3, // This will skip first two values + the initial value
expect: ['Hello world'],
)
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rxBlocFakeAsyncTest #
For the most complex test cases with multiple events, which contain throttleTime or/and debounceTime or similar inside, and to speed up test execution,rxBlocFakeAsyncTest should be used. It contains an instance of FakeAsync inside act, which provides a way to fire all asynchronous events that are scheduled for that time period without actually needing the test to wait for real time to elapse.
Example
DetailsBloc email state mapper:
@override
Stream<String> _mapToEmailState() => _$setEmailEvent
.startWith('')
.throttleTime(const Duration(seconds: 3), trailing: true)
.map((email) => email.trim())
.shareReplay(maxSize: 1);
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✅ GOOD - execution time ±35 ms:
rxBlocFakeAsyncTest<DetailsBloc, String>(
'Email fake async test bloc',
build: () => DetailsBloc(repo),
state: (bloc) => bloc.states.email,
act: (bloc, fakeAsync) {
bloc.events.setEmail(' job');
bloc.events.setEmail(' job@prime');
bloc.events.setEmail(' [email protected] ');

fakeAsync.elapse(const Duration(seconds: 3));
},
expect: <String>['', '[email protected]'],
);
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❌ BAD - execution time ±3 sec:
rxBlocTest<DetailsBloc, String>(
'Email test bloc',
build: () async => DetailsBloc(repo),
state: (bloc) => bloc.states.email,
act: (bloc) async {
bloc.events.setEmail(' job');
bloc.events.setEmail(' job@prime');
bloc.events.setEmail(' [email protected] ');
},
expect: <String>['', '[email protected]'],
);
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