Change --debug-port to --observatory-port (#7675)

...and add --diagnostic-port.

...and document port 0.

packages/flutter_tools/lib/src/android/android_device.dart

@@ -445,7 +445,7 @@ class AndroidDevice extends Device {
       Match match = discoverExp.firstMatch(line);
       if (match != null) {
         Map<String, dynamic> app = JSON.decode(match.group(1));
-        result.add(new DiscoveredApp(app['id'], app['observatoryPort']));
+        result.add(new DiscoveredApp(app['id'], app['observatoryPort'], app['diagnosticPort']));
       }
     });
 

packages/flutter_tools/lib/src/base/os.dart

@@ -163,6 +163,7 @@ Future<int> findPreferredPort(int defaultPort, { int searchStep: 2 }) async {
 
 Future<bool> _isPortAvailable(int port) async {
   try {
+    // TODO(ianh): This is super racy.
     ServerSocket socket = await ServerSocket.bind(InternetAddress.LOOPBACK_IP_V4, port);
     await socket.close();
     return true;

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

@@ -485,7 +485,8 @@ class AppDomain extends Domain {
     return apps.map((DiscoveredApp app) {
       return <String, dynamic>{
         'id': app.id,
-        'observatoryDevicePort': app.observatoryPort
+        'observatoryDevicePort': app.observatoryPort,
+        'diagnosticDevicePort': app.diagnosticPort,
       };
     }).toList();
   }

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

@@ -65,10 +65,7 @@ class DriveCommand extends RunCommandBase {
         'the application running after tests are done.'
     );
 
-    argParser.addOption('debug-port',
-      defaultsTo: kDefaultDrivePort.toString(),
-      help: 'Listen to the given port for a debug connection.'
-    );
+    usesPortOptions();
   }
 
   @override
@@ -87,7 +84,8 @@ class DriveCommand extends RunCommandBase {
   // ignore: cancel_subscriptions
   StreamSubscription<String> _deviceLogSubscription;
 
-  int get debugPort => int.parse(argResults['debug-port']);
+  int get observatoryPort => int.parse(argResults['observatory-port']);
+  int get diagnosticPort => int.parse(argResults['diagnostic-port']);
 
   @override
   Future<Null> verifyThenRunCommand() async {
@@ -315,7 +313,8 @@ Future<int> startApp(DriveCommand command) async {
     debuggingOptions: new DebuggingOptions.enabled(
       command.getBuildMode(),
       startPaused: true,
-      observatoryPort: command.debugPort
+      observatoryPort: command.observatoryPort,
+      diagnosticPort: command.diagnosticPort,
     ),
     platformArgs: platformArgs
   );

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

@@ -50,8 +50,7 @@ class RunCommand extends RunCommandBase {
         defaultsTo: false,
         negatable: false,
         help: 'Start in a paused mode and wait for a debugger to connect.');
-    argParser.addOption('debug-port',
-        help: 'Listen to the given port for a debug connection (defaults to $kDefaultObservatoryPort).');
+    usesPortOptions();
     argParser.addFlag('build',
         defaultsTo: true,
         help: 'If necessary, build the app before running.');
@@ -190,12 +189,21 @@ class RunCommand extends RunCommandBase {
       return null;
     }
 
-    int debugPort;
-    if (argResults['debug-port'] != null) {
+    int observatoryPort;
+    if (argResults['observatory-port'] != null) {
       try {
-        debugPort = int.parse(argResults['debug-port']);
+        observatoryPort = int.parse(argResults['observatory-port']);
       } catch (error) {
-        throwToolExit('Invalid port for `--debug-port`: $error');
+        throwToolExit('Invalid port for `--observatory-port`: $error');
+      }
+    }
+
+    int diagnosticPort;
+    if (argResults['diagnostic-port'] != null) {
+      try {
+        diagnosticPort = int.parse(argResults['diagnostic-port']);
+      } catch (error) {
+        throwToolExit('Invalid port for `--diagnostic-port`: $error');
       }
     }
 
@@ -210,7 +218,8 @@ class RunCommand extends RunCommandBase {
       options = new DebuggingOptions.enabled(
         getBuildMode(),
         startPaused: argResults['start-paused'],
-        observatoryPort: debugPort
+        observatoryPort: observatoryPort,
+        diagnosticPort: diagnosticPort,
       );
     }
 

packages/flutter_tools/lib/src/device.dart

@@ -313,6 +313,8 @@ class DebuggingOptions {
   /// Return the user specified diagnostic port. If that isn't available,
   /// return [kDefaultDiagnosticPort], or a port close to that one.
   Future<int> findBestDiagnosticPort() {
+    if (hasDiagnosticPort)
+      return new Future<int>.value(diagnosticPort);
     return findPreferredPort(diagnosticPort ?? kDefaultDiagnosticPort);
   }
 }
@@ -378,7 +380,8 @@ abstract class DeviceLogReader {
 
 /// Describes an app running on the device.
 class DiscoveredApp {
-  DiscoveredApp(this.id, this.observatoryPort);
+  DiscoveredApp(this.id, this.observatoryPort, this.diagnosticPort);
   final String id;
   final int observatoryPort;
+  final int diagnosticPort;
 }

packages/flutter_tools/lib/src/hot.dart

@@ -183,7 +183,6 @@ class HotRunner extends ResidentRunner {
       return 2;
     }
 
-
     try {
       Uri baseUri = await _initDevFS();
       if (connectionInfoCompleter != null) {

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

@@ -299,8 +299,8 @@ class IOSDevice extends Device {
 
     if (installationResult != 0) {
       printError('Could not install ${bundle.path} on $id.');
-      printError("Try launching XCode and selecting 'Product > Run' to fix the problem:");
-      printError("  open ios/Runner.xcodeproj");
+      printError('Try launching XCode and selecting "Product > Run" to fix the problem:');
+      printError('  open ios/Runner.xcodeproj');
       printError('');
       return new LaunchResult.failed();
     }

packages/flutter_tools/lib/src/ios/simulators.dart

@@ -453,6 +453,8 @@ class IOSSimulator extends Device {
 
       int observatoryPort = await debuggingOptions.findBestObservatoryPort();
       args.add("--observatory-port=$observatoryPort");
+      int diagnosticPort = await debuggingOptions.findBestDiagnosticPort();
+      args.add("--diagnostic-port=$diagnosticPort");
     }
 
     ProtocolDiscovery observatoryDiscovery;

packages/flutter_tools/lib/src/protocol_discovery.dart

@@ -63,14 +63,13 @@ class ProtocolDiscovery {
       hostPort = await portForwarder
           .forward(devicePort, hostPort: hostPort)
           .timeout(const Duration(seconds: 60), onTimeout: () {
-            throwToolExit('Timeout while atempting to foward device port $devicePort');
+            throwToolExit('Timeout while atempting to foward device port $devicePort for $_serviceName');
           });
-      printTrace('Forwarded host port $hostPort to device port $devicePort');
+      printTrace('Forwarded host port $hostPort to device port $devicePort for $_serviceName');
       hostUri = deviceUri.replace(port: hostPort);
     } else {
       hostUri = deviceUri;
     }
-    printStatus('$_serviceName listening on $hostUri');
     return hostUri;
   }
 

packages/flutter_tools/lib/src/resident_runner.dart

@@ -143,9 +143,8 @@ abstract class ResidentRunner {
   }
 
   Future<Null> startEchoingDeviceLog(ApplicationPackage app) async {
-    if (_loggingSubscription != null) {
+    if (_loggingSubscription != null)
       return;
-    }
     _loggingSubscription = device.getLogReader(app: app).logLines.listen((String line) {
       if (!line.contains('Observatory listening on http') &&
           !line.contains('Diagnostic server listening on http'))

packages/flutter_tools/lib/src/runner/flutter_command.dart

@@ -63,6 +63,19 @@ abstract class FlutterCommand extends Command<Null> {
     _usesPubOption = true;
   }
 
+  void usesPortOptions() {
+    argParser.addOption('observatory-port',
+        help: 'Listen to the given port for an observatory debugger connection.\n'
+              'Specifying port 0 will find a random free port.\n'
+              'Defaults to the first available port after $kDefaultObservatoryPort.'
+    );
+    argParser.addOption('diagnostic-port',
+        help: 'Listen to the given port for a diagnostic connection.\n'
+              'Specifying port 0 will find a random free port.\n'
+              'Defaults to the first available port after $kDefaultDiagnosticPort.'
+    );
+  }
+
   void addBuildModeFlags({ bool defaultToRelease: true }) {
     defaultBuildMode = defaultToRelease ? BuildMode.release : BuildMode.debug;