platform/sandbox/reactivex/test/transformers/backpressure/sample_test.dart

109 lines
3 KiB
Dart

import 'dart:async';
import 'package:angel3_reactivex/angel3_reactivex.dart';
import 'package:test/test.dart';
import '../../utils.dart';
Stream<int> _getStream() =>
Stream<int>.periodic(const Duration(milliseconds: 20), (count) => count)
.take(5);
Stream<int> _getSampleStream() =>
Stream<int>.periodic(const Duration(milliseconds: 35), (count) => count)
.take(10);
void main() {
test('Rx.sample', () async {
final stream = _getStream().sample(_getSampleStream());
await expectLater(stream, emitsInOrder(<dynamic>[1, 3, 4, emitsDone]));
});
test('Rx.sample.reusable', () async {
final transformer = SampleStreamTransformer<int>(
(_) => _getSampleStream().asBroadcastStream());
final streamA = _getStream().transform(transformer);
final streamB = _getStream().transform(transformer);
await expectLater(streamA, emitsInOrder(<dynamic>[1, 3, 4, emitsDone]));
await expectLater(streamB, emitsInOrder(<dynamic>[1, 3, 4, emitsDone]));
}, skip: true);
test('Rx.sample.onDone', () async {
final stream = Stream.value(1).sample(Stream<void>.empty());
await expectLater(stream, emits(1));
});
test('Rx.sample.shouldClose', () async {
final controller = StreamController<int>();
controller.stream
.sample(Stream<void>.empty()) // should trigger onDone
.listen(null, onDone: expectAsync0(() => expect(true, isTrue)));
controller.add(0);
controller.add(1);
controller.add(2);
controller.add(3);
scheduleMicrotask(controller.close);
});
test('Rx.sample.asBroadcastStream', () async {
final stream = _getStream()
.asBroadcastStream()
.sample(_getSampleStream().asBroadcastStream());
// listen twice on same stream
stream.listen(null);
stream.listen(null);
// code should reach here
await expectLater(true, true);
});
test('Rx.sample.error.shouldThrowA', () async {
final streamWithError =
Stream<void>.error(Exception()).sample(_getSampleStream());
streamWithError.listen(null,
onError: expectAsync2((Exception e, StackTrace s) {
expect(e, isException);
}));
});
test('Rx.sample.error.shouldThrowB', () async {
final streamWithError = Stream.value(1)
.sample(Stream<void>.error(Exception('Catch me if you can!')));
streamWithError.listen(null,
onError: expectAsync2((Exception e, StackTrace s) {
expect(e, isException);
}));
});
test('Rx.sample.pause.resume', () async {
final controller = StreamController<int>();
late StreamSubscription<int> subscription;
subscription = _getStream()
.sample(_getSampleStream())
.listen(controller.add, onDone: () {
controller.close();
subscription.cancel();
});
await expectLater(
controller.stream, emitsInOrder(<dynamic>[1, 3, 4, emitsDone]));
subscription.pause();
subscription.resume();
});
test('Rx.sample.nullable', () {
nullableTest<String?>(
(s) => s.sample(_getSampleStream()),
);
});
}