Eagerly wait for the driver extension on FlutterDriver.connect() (#56428)
diff --git a/packages/flutter_driver/lib/src/driver/vmservice_driver.dart b/packages/flutter_driver/lib/src/driver/vmservice_driver.dart
index af9a4fb..10859f5 100644
--- a/packages/flutter_driver/lib/src/driver/vmservice_driver.dart
+++ b/packages/flutter_driver/lib/src/driver/vmservice_driver.dart
@@ -8,7 +8,6 @@
import 'package:file/file.dart' as f;
import 'package:fuchsia_remote_debug_protocol/fuchsia_remote_debug_protocol.dart' as fuchsia;
-import 'package:json_rpc_2/error_code.dart' as error_code;
import 'package:json_rpc_2/json_rpc_2.dart' as rpc;
import 'package:meta/meta.dart';
import 'package:path/path.dart' as p;
@@ -150,11 +149,37 @@
}
/// Waits for a signal from the VM service that the extension is registered.
- /// Returns [_flutterExtensionMethodName]
- Future<String> waitForServiceExtension() {
- return isolate.onExtensionAdded.firstWhere((String extension) {
- return extension == _flutterExtensionMethodName;
- });
+ ///
+ /// Looks at the list of loaded extensions for the current [isolateRef], as
+ /// well as the stream of added extensions.
+ Future<void> waitForServiceExtension() async {
+ final Future<void> extensionAlreadyAdded = isolateRef
+ .loadRunnable()
+ .then((VMIsolate isolate) async {
+ if (isolate.extensionRpcs.contains(_flutterExtensionMethodName)) {
+ return;
+ }
+ // Never complete. Rely on the stream listener to find the service
+ // extension instead.
+ return Completer<void>().future;
+ });
+
+ final Completer<void> extensionAdded = Completer<void>();
+ StreamSubscription<String> isolateAddedSubscription;
+ isolateAddedSubscription = isolate.onExtensionAdded.listen(
+ (String extensionName) {
+ if (extensionName == _flutterExtensionMethodName) {
+ extensionAdded.complete();
+ isolateAddedSubscription.cancel();
+ }
+ },
+ onError: extensionAdded.completeError,
+ cancelOnError: true);
+
+ await Future.any(<Future<void>>[
+ extensionAlreadyAdded,
+ extensionAdded.future,
+ ]);
}
/// Tells the Dart VM Service to notify us about "Isolate" events.
@@ -174,25 +199,7 @@
if (isolate.pauseEvent is VMPauseStartEvent) {
_log('Isolate is paused at start.');
- // If the isolate is paused at the start, e.g. via the --start-paused
- // option, then the VM service extension is not registered yet. Wait for
- // it to be registered.
- await enableIsolateStreams();
- final Future<String> whenServiceExtensionReady = waitForServiceExtension();
- final Future<dynamic> whenResumed = resumeLeniently();
- await whenResumed;
-
- _log('Waiting for service extension');
- // We will never receive the extension event if the user does not
- // register it. If that happens, show a message but continue waiting.
- await _warnIfSlow<String>(
- future: whenServiceExtensionReady,
- timeout: kUnusuallyLongTimeout,
- message: 'Flutter Driver extension is taking a long time to become available. '
- 'Ensure your test app (often "lib/main.dart") imports '
- '"package:flutter_driver/driver_extension.dart" and '
- 'calls enableFlutterDriverExtension() as the first call in main().',
- );
+ await resumeLeniently();
} else if (isolate.pauseEvent is VMPauseExitEvent ||
isolate.pauseEvent is VMPauseBreakpointEvent ||
isolate.pauseEvent is VMPauseExceptionEvent ||
@@ -210,27 +217,20 @@
);
}
- // Invoked checkHealth and try to fix delays in the registration of Service
- // extensions
- Future<Health> checkHealth() async {
- try {
- // At this point the service extension must be installed. Verify it.
- return await driver.checkHealth();
- } on rpc.RpcException catch (e) {
- if (e.code != error_code.METHOD_NOT_FOUND) {
- rethrow;
- }
- _log(
- 'Check Health failed, try to wait for the service extensions to be '
- 'registered.'
- );
- await enableIsolateStreams();
- await waitForServiceExtension();
- return driver.checkHealth();
- }
- }
+ await enableIsolateStreams();
- final Health health = await checkHealth();
+ // We will never receive the extension event if the user does not register
+ // it. If that happens, show a message but continue waiting.
+ await _warnIfSlow<void>(
+ future: waitForServiceExtension(),
+ timeout: kUnusuallyLongTimeout,
+ message: 'Flutter Driver extension is taking a long time to become available. '
+ 'Ensure your test app (often "lib/main.dart") imports '
+ '"package:flutter_driver/driver_extension.dart" and '
+ 'calls enableFlutterDriverExtension() as the first call in main().',
+ );
+
+ final Health health = await driver.checkHealth();
if (health.status != HealthStatus.ok) {
await client.close();
throw DriverError('Flutter application health check failed.');
diff --git a/packages/flutter_driver/test/flutter_driver_test.dart b/packages/flutter_driver/test/flutter_driver_test.dart
index f60ad1b..b0d66d4 100644
--- a/packages/flutter_driver/test/flutter_driver_test.dart
+++ b/packages/flutter_driver/test/flutter_driver_test.dart
@@ -49,6 +49,10 @@
when(mockClient.getVM()).thenAnswer((_) => Future<MockVM>.value(mockVM));
when(mockVM.isolates).thenReturn(<VMRunnableIsolate>[mockIsolate]);
when(mockIsolate.loadRunnable()).thenAnswer((_) => Future<MockIsolate>.value(mockIsolate));
+ when(mockIsolate.extensionRpcs).thenReturn(<String>[]);
+ when(mockIsolate.onExtensionAdded).thenAnswer((Invocation invocation) {
+ return Stream<String>.fromIterable(<String>['ext.flutter.driver']);
+ });
when(mockIsolate.invokeExtension(any, any)).thenAnswer(
(Invocation invocation) => makeMockResponse(<String, dynamic>{'status': 'ok'}));
vmServiceConnectFunction = (String url, {Map<String, dynamic> headers}) {
@@ -81,7 +85,7 @@
final FlutterDriver driver = await FlutterDriver.connect(dartVmServiceUrl: '');
expect(driver, isNotNull);
expectLogContains('Isolate is paused at start');
- expect(connectionLog, <String>['streamListen', 'onExtensionAdded', 'resume']);
+ expect(connectionLog, <String>['resume', 'streamListen', 'onExtensionAdded']);
});
test('connects to isolate paused mid-flight', () async {
@@ -117,6 +121,18 @@
expectLogContains('Isolate is not paused. Assuming application is ready.');
});
+ test('connects to unpaused when onExtensionAdded does not contain the '
+ 'driver extension', () async {
+ when(mockIsolate.pauseEvent).thenReturn(MockVMResumeEvent());
+ when(mockIsolate.extensionRpcs).thenReturn(<String>['ext.flutter.driver']);
+ when(mockIsolate.onExtensionAdded).thenAnswer((Invocation invocation) {
+ return const Stream<String>.empty();
+ });
+ final FlutterDriver driver = await FlutterDriver.connect(dartVmServiceUrl: '');
+ expect(driver, isNotNull);
+ expectLogContains('Isolate is not paused. Assuming application is ready.');
+ });
+
test('connects with headers', () async {
Map<String, dynamic> actualHeaders;
vmServiceConnectFunction = (String url, {Map<String, dynamic> headers}) {
