Handle null exception case in ProxiedDevice.stopApp. (#113317)

packages/flutter_tools/lib/src/commands/daemon.dart

@@ -1025,8 +1025,11 @@ class DeviceDomain extends Domain {
     if (device == null) {
       throw DaemonException("device '$deviceId' not found");
     }
-    final String? applicationPackageId = _getStringArg(args, 'applicationPackageId', required: true);
-    final ApplicationPackage applicationPackage = _applicationPackages[applicationPackageId!]!;
+    final String? applicationPackageId = _getStringArg(args, 'applicationPackageId');
+    ApplicationPackage? applicationPackage;
+    if (applicationPackageId != null) {
+      applicationPackage = _applicationPackages[applicationPackageId];
+    }
     return device.stopApp(
       applicationPackage,
       userIdentifier: _getStringArg(args, 'userIdentifier'),

packages/flutter_tools/lib/src/proxied_devices/devices.dart

@@ -65,7 +65,7 @@ class ProxiedDevices extends DeviceDiscovery {
     final List<Map<String, Object?>> discoveredDevices = _cast<List<dynamic>>(await connection.sendRequest('device.discoverDevices')).cast<Map<String, Object?>>();
     final List<ProxiedDevice> devices = <ProxiedDevice>[
       for (final Map<String, Object?> device in discoveredDevices)
-        _deviceFromDaemonResult(device),
+        deviceFromDaemonResult(device),
     ];
 
     _devices = devices;
@@ -75,7 +75,8 @@ class ProxiedDevices extends DeviceDiscovery {
   @override
   List<String> get wellKnownIds => const <String>[];
 
-  ProxiedDevice _deviceFromDaemonResult(Map<String, Object?> device) {
+  @visibleForTesting
+  ProxiedDevice deviceFromDaemonResult(Map<String, Object?> device) {
     final Map<String, Object?> capabilities = _cast<Map<String, Object?>>(device['capabilities']);
     return ProxiedDevice(
       connection, _cast<String>(device['id']),
@@ -275,12 +276,13 @@ class ProxiedDevice extends Device {
 
   @override
   Future<bool> stopApp(
-    covariant PrebuiltApplicationPackage app, {
+    covariant PrebuiltApplicationPackage? app, {
     String? userIdentifier,
   }) async {
     return _cast<bool>(await connection.sendRequest('device.stopApp', <String, Object?>{
       'deviceId': id,
-      'applicationPackageId': await applicationPackageId(app),
+      if (app != null)
+        'applicationPackageId': await applicationPackageId(app),
       'userIdentifier': userIdentifier,
     }));
   }

packages/flutter_tools/test/general.shard/proxied_devices/proxied_devices_test.dart

@@ -14,32 +14,32 @@ import 'package:test/fake.dart';
 import '../../src/common.dart';
 
 void main() {
-  group('ProxiedPortForwarder', () {
-    late BufferLogger bufferLogger;
-    late DaemonConnection serverDaemonConnection;
-    late DaemonConnection clientDaemonConnection;
-    setUp(() {
-      bufferLogger = BufferLogger.test();
-      final FakeDaemonStreams serverDaemonStreams = FakeDaemonStreams();
-      serverDaemonConnection = DaemonConnection(
-        daemonStreams: serverDaemonStreams,
-        logger: bufferLogger,
-      );
-      final FakeDaemonStreams clientDaemonStreams = FakeDaemonStreams();
-      clientDaemonConnection = DaemonConnection(
-        daemonStreams: clientDaemonStreams,
-        logger: bufferLogger,
-      );
-
-      serverDaemonStreams.inputs.addStream(clientDaemonStreams.outputs.stream);
-      clientDaemonStreams.inputs.addStream(serverDaemonStreams.outputs.stream);
-    });
+  late BufferLogger bufferLogger;
+  late DaemonConnection serverDaemonConnection;
+  late DaemonConnection clientDaemonConnection;
+  setUp(() {
+    bufferLogger = BufferLogger.test();
+    final FakeDaemonStreams serverDaemonStreams = FakeDaemonStreams();
+    serverDaemonConnection = DaemonConnection(
+      daemonStreams: serverDaemonStreams,
+      logger: bufferLogger,
+    );
+    final FakeDaemonStreams clientDaemonStreams = FakeDaemonStreams();
+    clientDaemonConnection = DaemonConnection(
+      daemonStreams: clientDaemonStreams,
+      logger: bufferLogger,
+    );
+
+    serverDaemonStreams.inputs.addStream(clientDaemonStreams.outputs.stream);
+    clientDaemonStreams.inputs.addStream(serverDaemonStreams.outputs.stream);
+  });
 
-    tearDown(() async {
-      await serverDaemonConnection.dispose();
-      await clientDaemonConnection.dispose();
-    });
+  tearDown(() async {
+    await serverDaemonConnection.dispose();
+    await clientDaemonConnection.dispose();
+  });
 
+  group('ProxiedPortForwarder', () {
     testWithoutContext('works correctly without device id', () async {
       final FakeServerSocket fakeServerSocket = FakeServerSocket(200);
       final ProxiedPortForwarder portForwarder = ProxiedPortForwarder(
@@ -202,6 +202,41 @@ void main() {
       });
     });
   });
+
+  group('ProxiedDevice', () {
+    final Map<String, Object> fakeDevice = <String, Object>{
+      'name': 'device-name',
+      'id': 'device-id',
+      'category': 'mobile',
+      'platformType': 'android',
+      'platform': 'android-arm',
+      'emulator': true,
+      'ephemeral': false,
+      'sdk': 'Test SDK (1.2.3)',
+      'capabilities': <String, Object>{
+        'hotReload': true,
+        'hotRestart': true,
+        'screenshot': false,
+        'fastStart': false,
+        'flutterExit': true,
+        'hardwareRendering': true,
+        'startPaused': true,
+      },
+    };
+    testWithoutContext('calls stopApp without application package if not passed', () async {
+      bufferLogger = BufferLogger.test();
+      final ProxiedDevices proxiedDevices = ProxiedDevices(
+        clientDaemonConnection,
+        logger: bufferLogger,
+      );
+      final ProxiedDevice device = proxiedDevices.deviceFromDaemonResult(fakeDevice);
+      unawaited(device.stopApp(null, userIdentifier: 'user-id'));
+      final DaemonMessage message = await serverDaemonConnection.incomingCommands.first;
+      expect(message.data['id'], isNotNull);
+      expect(message.data['method'], 'device.stopApp');
+      expect(message.data['params'], <String, Object?>{'deviceId': 'device-id', 'userIdentifier': 'user-id'});
+    });
+  });
 }
 
 class FakeDaemonStreams implements DaemonStreams {