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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:async';
import 'package:flutter/widgets.dart';
import 'package:flutter_test/flutter_test.dart';
void main() {
Widget snapshotText(BuildContext context, AsyncSnapshot<String> snapshot) {
return Text(snapshot.toString(), textDirection: TextDirection.ltr);
}
group('AsyncSnapshot', () {
test('requiring data preserves the stackTrace', () {
final StackTrace originalStackTrace = StackTrace.current;
try {
AsyncSnapshot<String>.withError(
ConnectionState.done,
Error(),
originalStackTrace,
).requireData;
fail('requireData did not throw');
} catch (error, stackTrace) {
expect(stackTrace, originalStackTrace);
}
});
test('requiring data succeeds if data is present', () {
expect(
const AsyncSnapshot<String>.withData(ConnectionState.done, 'hello').requireData,
'hello',
);
});
test('requiring data fails if there is an error', () {
expect(
() => const AsyncSnapshot<String>.withError(ConnectionState.done, 'error').requireData,
throwsA(equals('error')),
);
});
test('requiring data fails if snapshot has neither data nor error', () {
expect(
() => const AsyncSnapshot<String>.nothing().requireData,
throwsStateError,
);
});
test('AsyncSnapshot basic constructors', () {
expect(const AsyncSnapshot<int>.nothing().connectionState, ConnectionState.none);
expect(const AsyncSnapshot<int>.nothing().data, isNull);
expect(const AsyncSnapshot<int>.nothing().error, isNull);
expect(const AsyncSnapshot<int>.nothing().stackTrace, isNull);
expect(const AsyncSnapshot<int>.waiting().connectionState, ConnectionState.waiting);
expect(const AsyncSnapshot<int>.waiting().data, isNull);
expect(const AsyncSnapshot<int>.waiting().error, isNull);
expect(const AsyncSnapshot<int>.waiting().stackTrace, isNull);
});
test('withError uses empty stack trace if no stack trace is specified', () {
// We need to store the error as a local variable in order for the
// equality check on the error to be true.
final Error error = Error();
expect(
AsyncSnapshot<int>.withError(ConnectionState.done, error),
AsyncSnapshot<int>.withError(ConnectionState.done, error),
);
});
});
group('Async smoke tests', () {
testWidgets('FutureBuilder', (WidgetTester tester) async {
await tester.pumpWidget(FutureBuilder<String>(
future: Future<String>.value('hello'),
builder: snapshotText,
));
await eventFiring(tester);
});
testWidgets('StreamBuilder', (WidgetTester tester) async {
await tester.pumpWidget(StreamBuilder<String>(
stream: Stream<String>.fromIterable(<String>['hello', 'world']),
builder: snapshotText,
));
await eventFiring(tester);
});
testWidgets('StreamFold', (WidgetTester tester) async {
await tester.pumpWidget(StringCollector(
stream: Stream<String>.fromIterable(<String>['hello', 'world']),
));
await eventFiring(tester);
});
});
group('FutureBuilder', () {
testWidgets('gracefully handles transition from null future', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
await tester.pumpWidget(FutureBuilder<String>(
key: key, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, null, null, null)'), findsOneWidget);
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(FutureBuilder<String>(
key: key, future: completer.future, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
});
testWidgets('gracefully handles transition to null future', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(FutureBuilder<String>(
key: key, future: completer.future, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
await tester.pumpWidget(FutureBuilder<String>(
key: key, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, null, null, null)'), findsOneWidget);
completer.complete('hello');
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, null, null, null)'), findsOneWidget);
});
testWidgets('gracefully handles transition to other future', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
final Completer<String> completerA = Completer<String>();
final Completer<String> completerB = Completer<String>();
await tester.pumpWidget(FutureBuilder<String>(
key: key, future: completerA.future, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
await tester.pumpWidget(FutureBuilder<String>(
key: key, future: completerB.future, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
completerB.complete('B');
completerA.complete('A');
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.done, B, null, null)'), findsOneWidget);
});
testWidgets('tracks life-cycle of Future to success', (WidgetTester tester) async {
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(FutureBuilder<String>(
future: completer.future, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
completer.complete('hello');
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.done, hello, null, null)'), findsOneWidget);
});
testWidgets('tracks life-cycle of Future to error', (WidgetTester tester) async {
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(FutureBuilder<String>(
future: completer.future, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
completer.completeError('bad', StackTrace.fromString('trace'));
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.done, null, bad, trace)'), findsOneWidget);
});
testWidgets('runs the builder using given initial data', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
await tester.pumpWidget(FutureBuilder<String>(
key: key,
builder: snapshotText,
initialData: 'I',
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, I, null, null)'), findsOneWidget);
});
testWidgets('ignores initialData when reconfiguring', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
await tester.pumpWidget(FutureBuilder<String>(
key: key,
builder: snapshotText,
initialData: 'I',
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, I, null, null)'), findsOneWidget);
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(FutureBuilder<String>(
key: key,
future: completer.future,
builder: snapshotText,
initialData: 'Ignored',
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, I, null, null)'), findsOneWidget);
});
testWidgets('debugRethrowError rethrows caught error', (WidgetTester tester) async {
FutureBuilder.debugRethrowError = true;
final Completer<void> caughtError = Completer<void>();
await runZonedGuarded(() async {
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(FutureBuilder<String>(
future: completer.future,
builder: snapshotText,
), const Duration(seconds: 1));
completer.completeError('bad');
}, (Object error, StackTrace stack) {
expectSync(error, equals('bad'));
caughtError.complete();
});
await tester.pumpAndSettle();
expectSync(caughtError.isCompleted, isTrue);
FutureBuilder.debugRethrowError = false;
});
});
group('StreamBuilder', () {
testWidgets('gracefully handles transition from null stream', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
await tester.pumpWidget(StreamBuilder<String>(
key: key, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, null, null, null)'), findsOneWidget);
final StreamController<String> controller = StreamController<String>();
await tester.pumpWidget(StreamBuilder<String>(
key: key, stream: controller.stream, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
});
testWidgets('gracefully handles transition to null stream', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
final StreamController<String> controller = StreamController<String>();
await tester.pumpWidget(StreamBuilder<String>(
key: key, stream: controller.stream, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
await tester.pumpWidget(StreamBuilder<String>(
key: key, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, null, null, null)'), findsOneWidget);
});
testWidgets('gracefully handles transition to other stream', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
final StreamController<String> controllerA = StreamController<String>();
final StreamController<String> controllerB = StreamController<String>();
await tester.pumpWidget(StreamBuilder<String>(
key: key, stream: controllerA.stream, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
await tester.pumpWidget(StreamBuilder<String>(
key: key, stream: controllerB.stream, builder: snapshotText,
));
controllerB.add('B');
controllerA.add('A');
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.active, B, null, null)'), findsOneWidget);
});
testWidgets('tracks events and errors of stream until completion', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
final StreamController<String> controller = StreamController<String>();
await tester.pumpWidget(StreamBuilder<String>(
key: key, stream: controller.stream, builder: snapshotText,
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsOneWidget);
controller.add('1');
controller.add('2');
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.active, 2, null, null)'), findsOneWidget);
controller.add('3');
controller.addError('bad', StackTrace.fromString('trace'));
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.active, null, bad, trace)'), findsOneWidget);
controller.add('4');
controller.close();
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.done, 4, null, null)'), findsOneWidget);
});
testWidgets('runs the builder using given initial data', (WidgetTester tester) async {
final StreamController<String> controller = StreamController<String>();
await tester.pumpWidget(StreamBuilder<String>(
stream: controller.stream,
builder: snapshotText,
initialData: 'I',
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, I, null, null)'), findsOneWidget);
});
testWidgets('ignores initialData when reconfiguring', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
await tester.pumpWidget(StreamBuilder<String>(
key: key,
builder: snapshotText,
initialData: 'I',
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, I, null, null)'), findsOneWidget);
final StreamController<String> controller = StreamController<String>();
await tester.pumpWidget(StreamBuilder<String>(
key: key,
stream: controller.stream,
builder: snapshotText,
initialData: 'Ignored',
));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, I, null, null)'), findsOneWidget);
});
});
group('FutureBuilder and StreamBuilder behave identically on Stream from Future', () {
testWidgets('when completing with data', (WidgetTester tester) async {
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(Column(children: <Widget>[
FutureBuilder<String>(future: completer.future, builder: snapshotText),
StreamBuilder<String>(stream: completer.future.asStream(), builder: snapshotText),
]));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsNWidgets(2));
completer.complete('hello');
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.done, hello, null, null)'), findsNWidgets(2));
});
testWidgets('when completing with error and with empty stack trace', (WidgetTester tester) async {
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(Column(children: <Widget>[
FutureBuilder<String>(future: completer.future, builder: snapshotText),
StreamBuilder<String>(stream: completer.future.asStream(), builder: snapshotText),
]));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsNWidgets(2));
completer.completeError('bad', StackTrace.empty);
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.done, null, bad, )'), findsNWidgets(2));
});
testWidgets('when completing with error and with stack trace', (WidgetTester tester) async {
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(Column(children: <Widget>[
FutureBuilder<String>(future: completer.future, builder: snapshotText),
StreamBuilder<String>(stream: completer.future.asStream(), builder: snapshotText),
]));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, null, null, null)'), findsNWidgets(2));
completer.completeError('bad', StackTrace.fromString('trace'));
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.done, null, bad, trace)'), findsNWidgets(2));
});
testWidgets('when Future is null', (WidgetTester tester) async {
await tester.pumpWidget(Column(children: <Widget>[
FutureBuilder<String>(builder: snapshotText),
StreamBuilder<String>(builder: snapshotText),
]));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, null, null, null)'), findsNWidgets(2));
});
testWidgets('when initialData is used with null Future and Stream', (WidgetTester tester) async {
await tester.pumpWidget(Column(children: <Widget>[
FutureBuilder<String>(builder: snapshotText, initialData: 'I'),
StreamBuilder<String>(builder: snapshotText, initialData: 'I'),
]));
expect(find.text('AsyncSnapshot<String>(ConnectionState.none, I, null, null)'), findsNWidgets(2));
});
testWidgets('when using initialData and completing with data', (WidgetTester tester) async {
final Completer<String> completer = Completer<String>();
await tester.pumpWidget(Column(children: <Widget>[
FutureBuilder<String>(future: completer.future, builder: snapshotText, initialData: 'I'),
StreamBuilder<String>(stream: completer.future.asStream(), builder: snapshotText, initialData: 'I'),
]));
expect(find.text('AsyncSnapshot<String>(ConnectionState.waiting, I, null, null)'), findsNWidgets(2));
completer.complete('hello');
await eventFiring(tester);
expect(find.text('AsyncSnapshot<String>(ConnectionState.done, hello, null, null)'), findsNWidgets(2));
});
});
group('StreamBuilderBase', () {
testWidgets('gracefully handles transition from null stream', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
await tester.pumpWidget(StringCollector(key: key));
expect(find.text(''), findsOneWidget);
final StreamController<String> controller = StreamController<String>();
await tester.pumpWidget(StringCollector(key: key, stream: controller.stream));
expect(find.text('conn'), findsOneWidget);
});
testWidgets('gracefully handles transition to null stream', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
final StreamController<String> controller = StreamController<String>();
await tester.pumpWidget(StringCollector(key: key, stream: controller.stream));
expect(find.text('conn'), findsOneWidget);
await tester.pumpWidget(StringCollector(key: key));
expect(find.text('conn, disc'), findsOneWidget);
});
testWidgets('gracefully handles transition to other stream', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
final StreamController<String> controllerA = StreamController<String>();
final StreamController<String> controllerB = StreamController<String>();
await tester.pumpWidget(StringCollector(key: key, stream: controllerA.stream));
await tester.pumpWidget(StringCollector(key: key, stream: controllerB.stream));
controllerA.add('A');
controllerB.add('B');
await eventFiring(tester);
expect(find.text('conn, disc, conn, data:B'), findsOneWidget);
});
testWidgets('tracks events and errors until completion', (WidgetTester tester) async {
final GlobalKey key = GlobalKey();
final StreamController<String> controller = StreamController<String>();
await tester.pumpWidget(StringCollector(key: key, stream: controller.stream));
controller.add('1');
controller.addError('bad', StackTrace.fromString('trace'));
controller.add('2');
controller.close();
await eventFiring(tester);
expect(find.text('conn, data:1, error:bad stackTrace:trace, data:2, done'), findsOneWidget);
});
});
}
Future<void> eventFiring(WidgetTester tester) async {
await tester.pump(Duration.zero);
}
class StringCollector extends StreamBuilderBase<String, List<String>> {
const StringCollector({ super.key, super.stream });
@override
List<String> initial() => <String>[];
@override
List<String> afterConnected(List<String> current) => current..add('conn');
@override
List<String> afterData(List<String> current, String data) => current..add('data:$data');
@override
List<String> afterError(List<String> current, dynamic error, StackTrace stackTrace) => current..add('error:$error stackTrace:$stackTrace');
@override
List<String> afterDone(List<String> current) => current..add('done');
@override
List<String> afterDisconnected(List<String> current) => current..add('disc');
@override
Widget build(BuildContext context, List<String> currentSummary) => Text(currentSummary.join(', '), textDirection: TextDirection.ltr);
}