IOSSimulator implementation.

Also fixes some minor bugs with iOS and Android interactions.

packages/flutter_tools/lib/src/application_package.dart

@@ -74,6 +74,7 @@ class ApplicationPackageFactory {
   static List<BuildPlatform> defaultBuildPlatforms = [
     BuildPlatform.android,
     BuildPlatform.iOS,
+    BuildPlatform.iOSSimulator,
   ];
 
   static Map<BuildPlatform, ApplicationPackage> getAvailableApplicationPackages(
@@ -95,6 +96,9 @@ class ApplicationPackageFactory {
         case BuildPlatform.iOS:
           packages[platform] = new IOSApp(buildPath);
           break;
+        case BuildPlatform.iOSSimulator:
+          packages[platform] = new IOSApp(buildPath);
+          break;
         default:
           // TODO(iansf): Add other platforms
           assert(false);

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

@@ -15,27 +15,38 @@ class InstallCommand extends Command {
   final name = 'install';
   final description = 'Install your Flutter app on attached devices.';
 
-  AndroidDevice android = null;
+  AndroidDevice android;
   IOSDevice ios;
+  IOSSimulator iosSim;
 
-  InstallCommand({this.android, this.ios});
+  InstallCommand({this.android, this.ios, this.iosSim}) {
+    argParser.addFlag('boot',
+        help: 'Boot the iOS Simulator if it isn\'t already running.');
+  }
 
   @override
   Future<int> run() async {
-    if (install()) {
+    if (install(argResults['boot'])) {
       return 0;
     } else {
       return 2;
     }
   }
 
-  bool install() {
+  bool install([bool boot = false]) {
     if (android == null) {
       android = new AndroidDevice();
     }
     if (ios == null) {
       ios = new IOSDevice();
     }
+    if (iosSim == null) {
+      iosSim = new IOSSimulator();
+    }
+
+    if (boot) {
+      iosSim.boot();
+    }
 
     bool installedSomewhere = false;
 
@@ -43,6 +54,7 @@ class InstallCommand extends Command {
         ApplicationPackageFactory.getAvailableApplicationPackages();
     ApplicationPackage androidApp = packages[BuildPlatform.android];
     ApplicationPackage iosApp = packages[BuildPlatform.iOS];
+    ApplicationPackage iosSimApp = packages[BuildPlatform.iOSSimulator];
 
     if (androidApp != null && android.isConnected()) {
       installedSomewhere = android.installApp(androidApp) || installedSomewhere;
@@ -52,6 +64,10 @@ class InstallCommand extends Command {
       installedSomewhere = ios.installApp(iosApp) || installedSomewhere;
     }
 
+    if (iosSimApp != null && iosSim.isConnected()) {
+      installedSomewhere = iosSim.installApp(iosSimApp) || installedSomewhere;
+    }
+
     return installedSomewhere;
   }
 }

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

@@ -18,8 +18,9 @@ class ListCommand extends Command {
   final description = 'List all connected devices.';
   AndroidDevice android;
   IOSDevice ios;
+  IOSSimulator iosSim;
 
-  ListCommand({this.android, this.ios}) {
+  ListCommand({this.android, this.ios, this.iosSim}) {
     argParser.addFlag('details',
         abbr: 'd',
         negatable: false,
@@ -54,6 +55,17 @@ class ListCommand extends Command {
       }
     }
 
+    if (details) {
+      print('iOS Simulators:');
+    }
+    for (IOSSimulator device in IOSSimulator.getAttachedDevices(iosSim)) {
+      if (details) {
+        print('${device.id}\t${device.name}');
+      } else {
+        print(device.id);
+      }
+    }
+
     return 0;
   }
 }

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

@@ -22,22 +22,25 @@ class ListenCommand extends Command {
       'on all connected devices.';
   AndroidDevice android;
   IOSDevice ios;
+  IOSSimulator iosSim;
   List<String> watchCommand;
 
   /// Only run once.  Used for testing.
   bool singleRun;
 
-  ListenCommand({this.android, this.ios, this.singleRun: false}) {}
+  ListenCommand({this.android, this.ios, this.iosSim, this.singleRun: false}) {}
 
   @override
   Future<int> run() async {
     if (android == null) {
       android = new AndroidDevice();
     }
-
     if (ios == null) {
       ios = new IOSDevice();
     }
+    if (iosSim == null) {
+      iosSim = new IOSSimulator();
+    }
 
     if (argResults.rest.length > 0) {
       watchCommand = _initWatchCommand(argResults.rest);
@@ -49,6 +52,7 @@ class ListenCommand extends Command {
         ApplicationPackageFactory.getAvailableApplicationPackages();
     ApplicationPackage androidApp = packages[BuildPlatform.android];
     ApplicationPackage iosApp = packages[BuildPlatform.iOS];
+    ApplicationPackage iosSimApp = packages[BuildPlatform.iOSSimulator];
 
     while (true) {
       _logging.info('Updating running Sky apps...');
@@ -66,7 +70,7 @@ class ListenCommand extends Command {
             // TODO(iansf): Don't rely on sky-src-path for the snapshotter.
             '--compiler',
             '${globalResults['sky-src-path']}'
-                '/out/ios_Debug/clang_x64/sky_snapshot'
+                '/out/ios_sim_Debug/clang_x64/sky_snapshot'
           ]);
         }
       } catch (e) {}
@@ -79,6 +83,10 @@ class ListenCommand extends Command {
         await ios.pushFile(iosApp, localFLXPath, remoteFLXPath);
       }
 
+      if (iosSim.isConnected()) {
+        await iosSim.pushFile(iosSimApp, localFLXPath, remoteFLXPath);
+      }
+
       if (android.isConnected()) {
         await android.startServer(
             argResults['target'], true, argResults['checked'], androidApp);

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

@@ -18,8 +18,9 @@ class LogsCommand extends Command {
   final description = 'Show logs for running Sky apps.';
   AndroidDevice android;
   IOSDevice ios;
+  IOSSimulator iosSim;
 
-  LogsCommand({this.android, this.ios}) {
+  LogsCommand({this.android, this.ios, this.iosSim}) {
     argParser.addFlag('clear',
         negatable: false,
         help: 'Clear log history before reading from logs (Android only).');
@@ -33,6 +34,9 @@ class LogsCommand extends Command {
     if (ios == null) {
       ios = new IOSDevice();
     }
+    if (iosSim == null) {
+      iosSim = new IOSSimulator();
+    }
 
     Future<int> androidLogProcess = null;
     if (android.isConnected()) {
@@ -44,6 +48,11 @@ class LogsCommand extends Command {
       iosLogProcess = ios.logs(clear: argResults['clear']);
     }
 
+    Future<int> iosSimLogProcess = null;
+    if (iosSim.isConnected()) {
+      iosSimLogProcess = iosSim.logs(clear: argResults['clear']);
+    }
+
     if (androidLogProcess != null) {
       await androidLogProcess;
     }
@@ -52,6 +61,10 @@ class LogsCommand extends Command {
       await iosLogProcess;
     }
 
+    if (iosSimLogProcess != null) {
+      await iosSimLogProcess;
+    }
+
     return 0;
   }
 }

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

@@ -20,10 +20,11 @@ final Logger _logging = new Logger('sky_tools.start');
 class StartCommand extends Command {
   final name = 'start';
   final description = 'Start your Flutter app on attached devices.';
-  AndroidDevice android = null;
-  IOSDevice ios = null;
+  AndroidDevice android;
+  IOSDevice ios;
+  IOSSimulator iosSim;
 
-  StartCommand({this.android, this.ios}) {
+  StartCommand({this.android, this.ios, this.iosSim}) {
     argParser.addFlag('poke',
         negatable: false,
         help: 'Restart the connection to the server (Android only).');
@@ -35,6 +36,8 @@ class StartCommand extends Command {
         defaultsTo: '.',
         abbr: 't',
         help: 'Target app path or filename to start.');
+    argParser.addFlag('boot',
+        help: 'Boot the iOS Simulator if it isn\'t already running.');
   }
 
   @override
@@ -45,6 +48,9 @@ class StartCommand extends Command {
     if (ios == null) {
       ios = new IOSDevice();
     }
+    if (iosSim == null) {
+      iosSim = new IOSSimulator();
+    }
 
     bool startedSomewhere = false;
     bool poke = argResults['poke'];
@@ -53,28 +59,32 @@ class StartCommand extends Command {
       stopper.stop();
 
       // Only install if the user did not specify a poke
-      InstallCommand installer = new InstallCommand(android: android, ios: ios);
-      installer.install();
+      InstallCommand installer =
+          new InstallCommand(android: android, ios: ios, iosSim: iosSim);
+      installer.install(argResults['boot']);
     }
 
     Map<BuildPlatform, ApplicationPackage> packages =
         ApplicationPackageFactory.getAvailableApplicationPackages();
+    ApplicationPackage androidApp = packages[BuildPlatform.android];
+    ApplicationPackage iosApp = packages[BuildPlatform.iOS];
+    ApplicationPackage iosSimApp = packages[BuildPlatform.iOSSimulator];
 
     bool startedOnAndroid = false;
-    if (android.isConnected()) {
-      ApplicationPackage androidApp = packages[BuildPlatform.android];
-
+    if (androidApp != null && android.isConnected()) {
       String target = path.absolute(argResults['target']);
       startedOnAndroid = await android.startServer(
           target, poke, argResults['checked'], androidApp);
     }
 
-    if (ios.isConnected()) {
-      ApplicationPackage iosApp = packages[BuildPlatform.iOS];
-
+    if (iosApp != null && ios.isConnected()) {
       startedSomewhere = await ios.startApp(iosApp) || startedSomewhere;
     }
 
+    if (iosSimApp != null && iosSim.isConnected()) {
+      startedSomewhere = await iosSim.startApp(iosSimApp) || startedSomewhere;
+    }
+
     if (startedSomewhere || startedOnAndroid) {
       return 0;
     } else {

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

@@ -17,10 +17,11 @@ final Logger _logging = new Logger('sky_tools.stop');
 class StopCommand extends Command {
   final name = 'stop';
   final description = 'Stop your Flutter app on all attached devices.';
-  AndroidDevice android = null;
-  IOSDevice ios = null;
+  AndroidDevice android;
+  IOSDevice ios;
+  IOSSimulator iosSim;
 
-  StopCommand({this.android, this.ios});
+  StopCommand({this.android, this.ios, this.iosSim});
 
   @override
   Future<int> run() async {
@@ -38,6 +39,9 @@ class StopCommand extends Command {
     if (ios == null) {
       ios = new IOSDevice();
     }
+    if (iosSim == null) {
+      iosSim = new IOSSimulator();
+    }
 
     bool stoppedSomething = false;
     Map<BuildPlatform, ApplicationPackage> packages =
@@ -53,6 +57,11 @@ class StopCommand extends Command {
       stoppedSomething = await ios.stopApp(iosApp) || stoppedSomething;
     }
 
+    if (iosSim.isConnected()) {
+      ApplicationPackage iosApp = packages[BuildPlatform.iOSSimulator];
+      stoppedSomething = await iosSim.stopApp(iosApp) || stoppedSomething;
+    }
+
     return stoppedSomething;
   }
 }

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

@@ -21,7 +21,7 @@ class TraceCommand extends Command {
       'To start a trace, wait, and then stop the trace, don\'t set any flags '
       'except (optionally) duration.\n'
       'Otherwise, specify either start or stop to manually control the trace.';
-  AndroidDevice android = null;
+  AndroidDevice android;
 
   TraceCommand([this.android]) {
     argParser.addFlag('start', negatable: false, help: 'Start tracing.');

packages/flutter_tools/lib/src/device.dart

@@ -26,6 +26,8 @@ abstract class _Device {
         id = AndroidDevice.defaultDeviceID;
       } else if (className == IOSDevice.className) {
         id = IOSDevice.defaultDeviceID;
+      } else if (className == IOSSimulator.className) {
+        id = IOSSimulator.defaultDeviceID;
       } else {
         throw 'Attempted to create a Device of unknown type $className';
       }
@@ -40,6 +42,10 @@ abstract class _Device {
         final device = new IOSDevice._(id);
         _deviceCache[id] = device;
         return device;
+      } else if (className == IOSSimulator.className) {
+        final device = new IOSSimulator._(id);
+        _deviceCache[id] = device;
+        return device;
       } else {
         throw 'Attempted to create a Device of unknown type $className';
       }
@@ -128,10 +134,13 @@ class IOSDevice extends _Device {
     return devices;
   }
 
-  static List<String> _getAttachedDeviceIDs([IOSDevice mockIOS]) {
+  static Iterable<String> _getAttachedDeviceIDs([IOSDevice mockIOS]) {
     String listerPath =
         (mockIOS != null) ? mockIOS.listerPath : _checkForCommand('idevice_id');
-    return runSync([listerPath, '-l']).trim().split('\n');
+    return runSync([listerPath, '-l'])
+        .trim()
+        .split('\n')
+        .where((String s) => s != null && s.length > 0);
   }
 
   static String _getDeviceName(String deviceID, [IOSDevice mockIOS]) {
@@ -163,17 +172,22 @@ class IOSDevice extends _Device {
 
   @override
   bool installApp(ApplicationPackage app) {
-    if (id == defaultDeviceID) {
-      runCheckedSync([installerPath, '-i', app.appPath]);
-    } else {
-      runCheckedSync([installerPath, '-u', id, '-i', app.appPath]);
+    try {
+      if (id == defaultDeviceID) {
+        runCheckedSync([installerPath, '-i', app.appPath]);
+      } else {
+        runCheckedSync([installerPath, '-u', id, '-i', app.appPath]);
+      }
+      return true;
+    } catch (e) {
+      return false;
     }
     return false;
   }
 
   @override
   bool isConnected() {
-    List<String> ids = _getAttachedDeviceIDs();
+    Iterable<String> ids = _getAttachedDeviceIDs();
     for (String id in ids) {
       if (id == this.id || this.id == defaultDeviceID) {
         return true;
@@ -245,12 +259,234 @@ class IOSDevice extends _Device {
   }
 
   /// Note that clear is not supported on iOS at this time.
-  Future<int> logs({bool clear: false}) {
+  Future<int> logs({bool clear: false}) async {
+    if (!isConnected()) {
+      return 2;
+    }
     return runCommandAndStreamOutput([loggerPath],
         prefix: 'IOS DEV: ', filter: new RegExp(r'.*SkyShell.*'));
   }
 }
 
+class IOSSimulator extends _Device {
+  static const String className = 'IOSSimulator';
+  static final String defaultDeviceID = 'default_ios_sim_id';
+
+  static const String _macInstructions =
+      'To work with iOS devices, please install ideviceinstaller. '
+      'If you use homebrew, you can install it with '
+      '"\$ brew install ideviceinstaller".';
+
+  static String _xcrunPath = path.join('/usr', 'bin', 'xcrun');
+
+  String _iOSSimPath;
+  String get iOSSimPath => _iOSSimPath;
+
+  String get xcrunPath => _xcrunPath;
+
+  String _name;
+  String get name => _name;
+
+  factory IOSSimulator({String id, String name, String iOSSimulatorPath}) {
+    IOSSimulator device = new _Device(className, id);
+    device._name = name;
+    if (iOSSimulatorPath == null) {
+      iOSSimulatorPath = path.join('/Applications', 'iOS Simulator.app',
+          'Contents', 'MacOS', 'iOS Simulator');
+    }
+    device._iOSSimPath = iOSSimulatorPath;
+    return device;
+  }
+
+  IOSSimulator._(String id) : super._(id) {}
+
+  static String _getRunningSimulatorID([IOSSimulator mockIOS]) {
+    String xcrunPath = mockIOS != null ? mockIOS.xcrunPath : _xcrunPath;
+    String output = runCheckedSync([xcrunPath, 'simctl', 'list', 'devices']);
+
+    Match match;
+    Iterable<Match> matches = new RegExp(r'[^\(]+\(([^\)]+)\) \(Booted\)',
+        multiLine: true).allMatches(output);
+    if (matches.length > 1) {
+      // More than one simulator is listed as booted, which is not allowed but
+      // sometimes happens erroneously.  Kill them all because we don't know
+      // which one is actually running.
+      _logging.warning('Multiple running simulators were detected, '
+          'which is not supposed to happen.');
+      for (Match m in matches) {
+        if (m.groupCount > 0) {
+          _logging.warning('Killing simulator ${m.group(1)}');
+          runSync([xcrunPath, 'simctl', 'shutdown', m.group(1)]);
+        }
+      }
+    } else if (matches.length == 1) {
+      match = matches.first;
+    }
+
+    if (match != null && match.groupCount > 0) {
+      return match.group(1);
+    } else {
+      _logging.info('No running simulators found');
+      return null;
+    }
+  }
+
+  String _getSimulatorPath() {
+    String deviceID = id == defaultDeviceID ? _getRunningSimulatorID() : id;
+    String homeDirectory = path.absolute(Platform.environment['HOME']);
+    if (deviceID == null) {
+      return null;
+    }
+    return path.join(homeDirectory, 'Library', 'Developer', 'CoreSimulator',
+        'Devices', deviceID);
+  }
+
+  String _getSimulatorAppHomeDirectory(ApplicationPackage app) {
+    String simulatorPath = _getSimulatorPath();
+    if (simulatorPath == null) {
+      return null;
+    }
+    return path.join(simulatorPath, 'data');
+  }
+
+  static List<IOSSimulator> getAttachedDevices([IOSSimulator mockIOS]) {
+    List<IOSSimulator> devices = [];
+    String id = _getRunningSimulatorID(mockIOS);
+    if (id != null) {
+      // TODO(iansf): get the simulator's name
+      // String name = _getDeviceName(id, mockIOS);
+      devices.add(new IOSSimulator(id: id));
+    }
+    return devices;
+  }
+
+  Future<bool> boot() async {
+    if (!Platform.isMacOS) {
+      return false;
+    }
+    if (isConnected()) {
+      return true;
+    }
+    if (id == defaultDeviceID) {
+      runDetached([iOSSimPath]);
+
+      Future<bool> checkConnection([int attempts = 20]) async {
+        if (attempts == 0) {
+          _logging.info('Timed out waiting for iOS Simulator $id to boot.');
+          return false;
+        }
+        if (!isConnected()) {
+          _logging.info('Waiting for iOS Simulator $id to boot...');
+          return new Future.delayed(new Duration(milliseconds: 500),
+              () => checkConnection(attempts - 1));
+        }
+        return true;
+      }
+      return checkConnection();
+    } else {
+      try {
+        runCheckedSync([xcrunPath, 'simctl', 'boot', id]);
+      } catch (e) {
+        _logging.warning('Unable to boot iOS Simulator $id: ', e);
+        return false;
+      }
+    }
+    return false;
+  }
+
+  @override
+  bool installApp(ApplicationPackage app) {
+    if (!isConnected()) {
+      return false;
+    }
+    try {
+      if (id == defaultDeviceID) {
+        runCheckedSync([xcrunPath, 'simctl', 'install', 'booted', app.appPath]);
+      } else {
+        runCheckedSync([xcrunPath, 'simctl', 'install', id, app.appPath]);
+      }
+      return true;
+    } catch (e) {
+      return false;
+    }
+  }
+
+  @override
+  bool isConnected() {
+    if (!Platform.isMacOS) {
+      return false;
+    }
+    String simulatorID = _getRunningSimulatorID();
+    if (simulatorID == null) {
+      return false;
+    } else if (id == defaultDeviceID) {
+      return true;
+    } else {
+      return _getRunningSimulatorID() == id;
+    }
+  }
+
+  @override
+  bool isAppInstalled(ApplicationPackage app) {
+    try {
+      String simulatorHomeDirectory = _getSimulatorAppHomeDirectory(app);
+      return FileSystemEntity.isDirectorySync(simulatorHomeDirectory);
+    } catch (e) {
+      return false;
+    }
+  }
+
+  @override
+  Future<bool> startApp(ApplicationPackage app) async {
+    if (!isAppInstalled(app)) {
+      return false;
+    }
+    try {
+      if (id == defaultDeviceID) {
+        runCheckedSync(
+            [xcrunPath, 'simctl', 'launch', 'booted', app.appPackageID]);
+      } else {
+        runCheckedSync([xcrunPath, 'simctl', 'launch', id, app.appPackageID]);
+      }
+      return true;
+    } catch (e) {
+      return false;
+    }
+  }
+
+  @override
+  Future<bool> stopApp(ApplicationPackage app) async {
+    // Currently we don't have a way to stop an app running on iOS.
+    return false;
+  }
+
+  Future<bool> pushFile(
+      ApplicationPackage app, String localFile, String targetFile) async {
+    if (Platform.isMacOS) {
+      String simulatorHomeDirectory = _getSimulatorAppHomeDirectory(app);
+      runCheckedSync(
+          ['cp', localFile, path.join(simulatorHomeDirectory, targetFile)]);
+      return true;
+    }
+    return false;
+  }
+
+  Future<int> logs({bool clear: false}) async {
+    if (!isConnected()) {
+      return 2;
+    }
+    String homeDirectory = path.absolute(Platform.environment['HOME']);
+    String simulatorDeviceID = _getRunningSimulatorID();
+    String logFilePath = path.join(homeDirectory, 'Library', 'Logs',
+        'CoreSimulator', simulatorDeviceID, 'system.log');
+    if (clear) {
+      runSync(['rm', logFilePath]);
+    }
+    return runCommandAndStreamOutput(['tail', '-f', logFilePath],
+        prefix: 'IOS SIM: ', filter: new RegExp(r'.*SkyShell.*'));
+  }
+}
+
 class AndroidDevice extends _Device {
   static const String _ADB_PATH = 'adb';
   static const String _observatoryPort = '8181';
@@ -576,7 +812,11 @@ class AndroidDevice extends _Device {
     runSync([adbPath, 'logcat', '-c']);
   }
 
-  Future<int> logs({bool clear: false}) {
+  Future<int> logs({bool clear: false}) async {
+    if (!isConnected()) {
+      return 2;
+    }
+
     if (clear) {
       clearLogs();
     }

packages/flutter_tools/lib/src/process.dart

@@ -22,7 +22,7 @@ Future<int> runCommandAndStreamOutput(List<String> cmd,
   proc.stdout.transform(UTF8.decoder).listen((String data) {
     List<String> dataLines = data.trimRight().split('\n');
     if (filter != null) {
-      dataLines = dataLines.where((String s) => filter.hasMatch(s));
+      dataLines = dataLines.where((String s) => filter.hasMatch(s)).toList();
     }
     if (dataLines.length > 0) {
       stdout.write('$prefix${dataLines.join('\n$prefix')}\n');
@@ -41,17 +41,21 @@ Future<int> runCommandAndStreamOutput(List<String> cmd,
 }
 
 Future runAndKill(List<String> cmd, Duration timeout) async {
-  _logging.info(cmd.join(' '));
-  Future<Process> proc = Process.start(
-      cmd[0], cmd.getRange(1, cmd.length).toList(),
-      mode: ProcessStartMode.DETACHED);
-
+  Future<Process> proc = runDetached(cmd);
   return new Future.delayed(timeout, () async {
     _logging.info('Intentionally killing ${cmd[0]}');
     Process.killPid((await proc).pid);
   });
 }
 
+Future<Process> runDetached(List<String> cmd) async {
+  _logging.info(cmd.join(' '));
+  Future<Process> proc = Process.start(
+      cmd[0], cmd.getRange(1, cmd.length).toList(),
+      mode: ProcessStartMode.DETACHED);
+  return proc;
+}
+
 /// Run cmd and return stdout.
 /// Throws an error if cmd exits with a non-zero value.
 String runCheckedSync(List<String> cmd) =>

packages/flutter_tools/test/install_test.dart

@@ -26,6 +26,10 @@ defineTests() {
       when(ios.isConnected()).thenReturn(false);
       when(ios.installApp(any)).thenReturn(false);
 
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      when(iosSim.isConnected()).thenReturn(false);
+      when(iosSim.installApp(any)).thenReturn(false);
+
       InstallCommand command = new InstallCommand(android: android, ios: ios);
 
       CommandRunner runner = new CommandRunner('test_flutter', '')
@@ -44,7 +48,12 @@ defineTests() {
       when(ios.isConnected()).thenReturn(true);
       when(ios.installApp(any)).thenReturn(true);
 
-      InstallCommand command = new InstallCommand(android: android, ios: ios);
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      when(iosSim.isConnected()).thenReturn(false);
+      when(iosSim.installApp(any)).thenReturn(false);
+
+      InstallCommand command =
+          new InstallCommand(android: android, ios: ios, iosSim: iosSim);
 
       CommandRunner runner = new CommandRunner('test_flutter', '')
         ..addCommand(command);

packages/flutter_tools/test/list_test.dart

@@ -30,7 +30,13 @@ defineTests() {
       when(ios.installerPath).thenReturn('echo');
       when(ios.listerPath).thenReturn('echo');
 
-      ListCommand command = new ListCommand(android: android, ios: ios);
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      // Avoid relying on xcrun being installed on the test system.
+      // Instead, cause the test to run the echo command.
+      when(iosSim.xcrunPath).thenReturn('echo');
+
+      ListCommand command =
+          new ListCommand(android: android, ios: ios, iosSim: iosSim);
       CommandRunner runner = new CommandRunner('test_flutter', '')
         ..addCommand(command);
       runner.run(['list']).then((int code) => expect(code, equals(0)));

packages/flutter_tools/test/listen_test.dart

@@ -22,8 +22,10 @@ defineTests() {
       when(android.isConnected()).thenReturn(false);
       MockIOSDevice ios = new MockIOSDevice();
       when(ios.isConnected()).thenReturn(false);
-      ListenCommand command =
-          new ListenCommand(android: android, ios: ios, singleRun: true);
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      when(iosSim.isConnected()).thenReturn(false);
+      ListenCommand command = new ListenCommand(
+          android: android, ios: ios, iosSim: iosSim, singleRun: true);
 
       CommandRunner runner = new CommandRunner('test_flutter', '')
         ..addCommand(command);

packages/flutter_tools/test/logs_test.dart

@@ -22,8 +22,11 @@ defineTests() {
       when(android.isConnected()).thenReturn(false);
       MockIOSDevice ios = new MockIOSDevice();
       when(ios.isConnected()).thenReturn(false);
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      when(iosSim.isConnected()).thenReturn(false);
 
-      LogsCommand command = new LogsCommand(android: android, ios: ios);
+      LogsCommand command =
+          new LogsCommand(android: android, ios: ios, iosSim: iosSim);
 
       CommandRunner runner = new CommandRunner('test_flutter', '')
         ..addCommand(command);

packages/flutter_tools/test/src/common.dart

@@ -16,10 +16,17 @@ class MockIOSDevice extends Mock implements IOSDevice {
   dynamic noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
 
+class MockIOSSimulator extends Mock implements IOSSimulator {
+  @override
+  dynamic noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
+}
+
 void applicationPackageSetup() {
   ApplicationPackageFactory.srcPath = './';
   ApplicationPackageFactory.setBuildPath(
       BuildType.prebuilt, BuildPlatform.android, './');
   ApplicationPackageFactory.setBuildPath(
       BuildType.prebuilt, BuildPlatform.iOS, './');
+  ApplicationPackageFactory.setBuildPath(
+      BuildType.prebuilt, BuildPlatform.iOSSimulator, './');
 }

packages/flutter_tools/test/start_test.dart

@@ -28,9 +28,16 @@ defineTests() {
       when(ios.isConnected()).thenReturn(false);
       when(ios.installApp(any)).thenReturn(false);
       when(ios.startApp(any)).thenReturn(false);
-      when(ios.startApp(any)).thenReturn(false);
+      when(ios.stopApp(any)).thenReturn(false);
 
-      StartCommand command = new StartCommand(android: android, ios: ios);
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      when(iosSim.isConnected()).thenReturn(false);
+      when(iosSim.installApp(any)).thenReturn(false);
+      when(iosSim.startApp(any)).thenReturn(false);
+      when(iosSim.stopApp(any)).thenReturn(false);
+
+      StartCommand command =
+          new StartCommand(android: android, ios: ios, iosSim: iosSim);
 
       CommandRunner runner = new CommandRunner('test_flutter', '')
         ..addCommand(command);
@@ -52,7 +59,14 @@ defineTests() {
       when(ios.startApp(any)).thenReturn(true);
       when(ios.stopApp(any)).thenReturn(false);
 
-      StartCommand command = new StartCommand(android: android, ios: ios);
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      when(iosSim.isConnected()).thenReturn(false);
+      when(iosSim.installApp(any)).thenReturn(false);
+      when(iosSim.startApp(any)).thenReturn(false);
+      when(iosSim.stopApp(any)).thenReturn(false);
+
+      StartCommand command =
+          new StartCommand(android: android, ios: ios, iosSim: iosSim);
 
       CommandRunner runner = new CommandRunner('test_flutter', '')
         ..addCommand(command);

packages/flutter_tools/test/stop_test.dart

@@ -26,7 +26,12 @@ defineTests() {
       when(ios.isConnected()).thenReturn(false);
       when(ios.stopApp(any)).thenReturn(false);
 
-      StopCommand command = new StopCommand(android: android, ios: ios);
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      when(iosSim.isConnected()).thenReturn(false);
+      when(iosSim.stopApp(any)).thenReturn(false);
+
+      StopCommand command =
+          new StopCommand(android: android, ios: ios, iosSim: iosSim);
 
       CommandRunner runner = new CommandRunner('test_flutter', '')
         ..addCommand(command);
@@ -44,7 +49,12 @@ defineTests() {
       when(ios.isConnected()).thenReturn(true);
       when(ios.stopApp(any)).thenReturn(true);
 
-      StopCommand command = new StopCommand(android: android, ios: ios);
+      MockIOSSimulator iosSim = new MockIOSSimulator();
+      when(iosSim.isConnected()).thenReturn(false);
+      when(iosSim.stopApp(any)).thenReturn(false);
+
+      StopCommand command =
+          new StopCommand(android: android, ios: ios, iosSim: iosSim);
 
       CommandRunner runner = new CommandRunner('test_flutter', '')
         ..addCommand(command);