[flutter_tools] write test to convince self of lack of timing issue (#58011)
In #55864 a race condition was described where a done event is received before we finish connecting. This cannot happen, since async functions begin synchronously and the flag isWaitingForVm is tripped immediately, keeping onDone from exiting.
diff --git a/packages/flutter_tools/test/general.shard/resident_runner_test.dart b/packages/flutter_tools/test/general.shard/resident_runner_test.dart
index 319df1a..040ed0e 100644
--- a/packages/flutter_tools/test/general.shard/resident_runner_test.dart
+++ b/packages/flutter_tools/test/general.shard/resident_runner_test.dart
@@ -1198,6 +1198,48 @@
}) async => mockVMService,
}));
+ group('Timing test', () {
+ Completer<MockVMService> completer;
+
+ test('Can connect to observatory stream after receiving done event.', () => testbed.run(() async {
+ completer = Completer<MockVMService>();
+ fakeVmServiceHost = FakeVmServiceHost(requests: <VmServiceExpectation>[]);
+ final MockDevice mockDevice = MockDevice();
+ final MockDeviceLogReader mockLogReader = MockDeviceLogReader();
+ when(mockDevice.getLogReader(app: anyNamed('app'))).thenReturn(mockLogReader);
+ final StreamController<Uri> controller = StreamController<Uri>();
+
+ final TestFlutterDevice flutterDevice = TestFlutterDevice(
+ mockDevice,
+ observatoryUris: controller.stream,
+ );
+
+ final Future<void> connectResult = flutterDevice.connect();
+
+ // First add the observatory URI to connect to.
+ controller.add(testUri);
+
+ // Then close the stream.
+ await controller.close();
+
+ // Then complete the VM service connection.
+ completer.complete(mockVMService);
+
+ await connectResult;
+
+ verify(mockLogReader.connectedVMService = mockVMService);
+ }, overrides: <Type, Generator>{
+ VMServiceConnector: () => (Uri httpUri, {
+ ReloadSources reloadSources,
+ Restart restart,
+ CompileExpression compileExpression,
+ ReloadMethod reloadMethod,
+ io.CompressionOptions compression,
+ Device device,
+ }) async => completer.future,
+ }));
+ });
+
test('nextPlatform moves through expected platforms', () {
expect(nextPlatform('android', TestFeatureFlags()), 'iOS');
expect(nextPlatform('iOS', TestFeatureFlags()), 'fuchsia');
