add smoke driver test; find by tooltip; retry predicate

packages/flutter_driver/lib/src/driver.dart

@@ -151,8 +151,19 @@ class FlutterDriver {
     return Health.fromJson(await _sendCommand(new GetHealth()));
   }
 
+  /// Finds the UI element with the given [key].
   Future<ObjectRef> findByValueKey(dynamic key) async {
-    return ObjectRef.fromJson(await _sendCommand(new FindByValueKey(key)));
+    return ObjectRef.fromJson(await _sendCommand(new Find(new ByValueKey(key))));
+  }
+
+  /// Finds the UI element for the tooltip with the given [message].
+  Future<ObjectRef> findByTooltipMessage(String message) async {
+    return ObjectRef.fromJson(await _sendCommand(new Find(new ByTooltipMessage(message))));
+  }
+
+  /// Finds the text element with the given [text].
+  Future<ObjectRef> findByText(String text) async {
+    return ObjectRef.fromJson(await _sendCommand(new Find(new ByText(text))));
   }
 
   Future<Null> tap(ObjectRef ref) async {

packages/flutter_driver/lib/src/enum_util.dart

@@ -6,7 +6,8 @@
 ///
 /// In Dart enum names are prefixed with enum class name. For example, for
 /// `enum Vote { yea, nay }`, `Vote.yea.toString()` produces `"Vote.yea"`
-/// rather than just `"yea"` - the simple name.
+/// rather than just `"yea"` - the simple name. This class provides methods for
+/// getting and looking up by simple names.
 ///
 /// Example:
 ///

packages/flutter_driver/lib/src/error.dart

@@ -15,7 +15,13 @@ class DriverError extends Error {
   final dynamic originalError;
   final dynamic originalStackTrace;
 
-  String toString() => 'DriverError: $message';
+  String toString() {
+    return '''DriverError: $message
+Original error: $originalError
+Original stack trace:
+$originalStackTrace
+    ''';
+  }
 }
 
 // Whether someone redirected the log messages somewhere.

packages/flutter_driver/lib/src/extension.dart

@@ -5,6 +5,7 @@
 import 'dart:async';
 import 'dart:convert';
 import 'dart:developer';
+import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_test/src/instrumentation.dart';
 
@@ -50,14 +51,14 @@ class FlutterDriverExtension {
   FlutterDriverExtension() {
     _commandHandlers = {
       'get_health': getHealth,
-      'find_by_value_key': findByValueKey,
+      'find': find,
       'tap': tap,
       'get_text': getText,
     };
 
     _commandDeserializers = {
       'get_health': GetHealth.fromJson,
-      'find_by_value_key': FindByValueKey.fromJson,
+      'find': Find.fromJson,
       'tap': Tap.fromJson,
       'get_text': GetText.fromJson,
     };
@@ -72,41 +73,95 @@ class FlutterDriverExtension {
       <String, CommandDeserializerCallback>{};
 
   Future<ServiceExtensionResponse> call(Map<String, String> params) async {
-    String commandKind = params['kind'];
-    CommandHandlerCallback commandHandler = _commandHandlers[commandKind];
-    CommandDeserializerCallback commandDeserializer =
-        _commandDeserializers[commandKind];
-
-    if (commandHandler == null || commandDeserializer == null) {
-      return new ServiceExtensionResponse.error(
-        ServiceExtensionResponse.kInvalidParams,
-        'Extension $_extensionMethod does not support command $commandKind'
-      );
+    try {
+      String commandKind = params['kind'];
+      CommandHandlerCallback commandHandler = _commandHandlers[commandKind];
+      CommandDeserializerCallback commandDeserializer =
+          _commandDeserializers[commandKind];
+
+      if (commandHandler == null || commandDeserializer == null) {
+        return new ServiceExtensionResponse.error(
+          ServiceExtensionResponse.kInvalidParams,
+          'Extension $_extensionMethod does not support command $commandKind'
+        );
+      }
+
+      Command command = commandDeserializer(params);
+      return commandHandler(command).then((Result result) {
+        return new ServiceExtensionResponse.result(JSON.encode(result.toJson()));
+      }, onError: (e, s) {
+        _log.warning('$e:\n$s');
+        return new ServiceExtensionResponse.error(
+          ServiceExtensionResponse.kExtensionError, '$e');
+      });
+    } catch(error, stackTrace) {
+      _log.warning('Uncaught extension error: $error\n$stackTrace');
     }
-
-    Command command = commandDeserializer(params);
-    return commandHandler(command).then((Result result) {
-      return new ServiceExtensionResponse.result(JSON.encode(result.toJson()));
-    }, onError: (e, s) {
-      _log.warning('$e:\n$s');
-      return new ServiceExtensionResponse.error(
-        ServiceExtensionResponse.kExtensionError, '$e');
-    });
   }
 
   Future<Health> getHealth(GetHealth command) async => new Health(HealthStatus.ok);
 
-  Future<ObjectRef> findByValueKey(FindByValueKey command) async {
-    Element elem = await retry(() {
-      return prober.findElementByKey(new ValueKey<dynamic>(command.keyValue));
-    }, _kDefaultTimeout, _kDefaultPauseBetweenRetries);
+  Future<ObjectRef> find(Find command) async {
+    SearchSpecification searchSpec = command.searchSpec;
+    switch(searchSpec.runtimeType) {
+      case ByValueKey: return findByValueKey(searchSpec);
+      case ByTooltipMessage: return findByTooltipMessage(searchSpec);
+      case ByText: return findByText(searchSpec);
+    }
+    throw new DriverError('Unsupported search specification type ${searchSpec.runtimeType}');
+  }
 
-    ObjectRef elemRef = elem != null
-      ? new ObjectRef(_registerObject(elem))
+  /// Runs object [locator] repeatedly until it returns a non-`null` value.
+  ///
+  /// [descriptionGetter] describes the object to be waited for. It is used in
+  /// the warning printed should timeout happen.
+  Future<ObjectRef> _waitForObject(String descriptionGetter(), Object locator()) async {
+    Object object = await retry(locator, _kDefaultTimeout, _kDefaultPauseBetweenRetries, predicate: (object) {
+      return object != null;
+    }).catchError((dynamic error, stackTrace) {
+      _log.warning('Timed out waiting for ${descriptionGetter()}');
+      return null;
+    });
+
+    ObjectRef elemRef = object != null
+      ? new ObjectRef(_registerObject(object))
       : new ObjectRef.notFound();
     return new Future.value(elemRef);
   }
 
+  Future<ObjectRef> findByValueKey(ByValueKey byKey) async {
+    return _waitForObject(
+      () => 'element with key "${byKey.keyValue}" of type ${byKey.keyValueType}',
+      () {
+        return prober.findElementByKey(new ValueKey<dynamic>(byKey.keyValue));
+      }
+    );
+  }
+
+  Future<ObjectRef> findByTooltipMessage(ByTooltipMessage byTooltipMessage) async {
+    return _waitForObject(
+      () => 'tooltip with message "${byTooltipMessage.text}" on it',
+      () {
+        return prober.findElement((Element element) {
+          Widget widget = element.widget;
+
+          if (widget is Tooltip)
+            return widget.message == byTooltipMessage.text;
+
+          return false;
+        });
+      }
+    );
+  }
+
+  Future<ObjectRef> findByText(ByText byText) async {
+    return await _waitForObject(
+      () => 'text "${byText.text}"',
+      () {
+        return prober.findText(byText.text);
+      });
+  }
+
   Future<TapResult> tap(Tap command) async {
     Element target = await _dereferenceOrDie(command.targetRef);
     prober.tap(target);

packages/flutter_driver/lib/src/find.dart

@@ -7,11 +7,84 @@ import 'message.dart';
 
 const List<Type> _supportedKeyValueTypes = const <Type>[String, int];
 
-/// Command to find an element by a value key.
-class FindByValueKey extends Command {
-  final String kind = 'find_by_value_key';
+/// Command to find an element.
+class Find extends Command {
+  final String kind = 'find';
 
-  FindByValueKey(dynamic keyValue)
+  Find(this.searchSpec);
+
+  final SearchSpecification searchSpec;
+
+  Map<String, dynamic> toJson() => searchSpec.toJson();
+
+  static Find fromJson(Map<String, dynamic> json) {
+    return new Find(SearchSpecification.fromJson(json));
+  }
+
+  static _throwInvalidKeyValueType(String invalidType) {
+    throw new DriverError('Unsupported key value type $invalidType. Flutter Driver only supports ${_supportedKeyValueTypes.join(", ")}');
+  }
+}
+
+/// Describes how to the driver should search for elements.
+abstract class SearchSpecification extends Message {
+  String get searchSpecType;
+
+  static SearchSpecification fromJson(Map<String, dynamic> json) {
+    String searchSpecType = json['searchSpecType'];
+    switch(searchSpecType) {
+      case 'ByValueKey': return ByValueKey.fromJson(json);
+      case 'ByTooltipMessage': return ByTooltipMessage.fromJson(json);
+      case 'ByText': return ByText.fromJson(json);
+    }
+    throw new DriverError('Unsupported search specification type $searchSpecType');
+  }
+
+  Map<String, dynamic> toJson() => {
+    'searchSpecType': searchSpecType,
+  };
+}
+
+/// Tells [Find] to search by tooltip text.
+class ByTooltipMessage extends SearchSpecification {
+  final String searchSpecType = 'ByTooltipMessage';
+
+  ByTooltipMessage(this.text);
+
+  /// Tooltip message text.
+  final String text;
+
+  Map<String, dynamic> toJson() => super.toJson()..addAll({
+    'text': text,
+  });
+
+  static ByTooltipMessage fromJson(Map<String, dynamic> json) {
+    return new ByTooltipMessage(json['text']);
+  }
+}
+
+/// Tells [Find] to search for `Text` widget by text.
+class ByText extends SearchSpecification {
+  final String searchSpecType = 'ByText';
+
+  ByText(this.text);
+
+  final String text;
+
+  Map<String, dynamic> toJson() => super.toJson()..addAll({
+    'text': text,
+  });
+
+  static ByText fromJson(Map<String, dynamic> json) {
+    return new ByText(json['text']);
+  }
+}
+
+/// Tells [Find] to search by `ValueKey`.
+class ByValueKey extends SearchSpecification {
+  final String searchSpecType = 'ByValueKey';
+
+  ByValueKey(dynamic keyValue)
     : this.keyValue = keyValue,
       this.keyValueString = '$keyValue',
       this.keyValueType = '${keyValue.runtimeType}' {
@@ -30,19 +103,19 @@ class FindByValueKey extends Command {
   /// May be one of "String", "int". The list of supported types may change.
   final String keyValueType;
 
-  Map<String, dynamic> toJson() => {
+  Map<String, dynamic> toJson() => super.toJson()..addAll({
     'keyValueString': keyValueString,
     'keyValueType': keyValueType,
-  };
+  });
 
-  static FindByValueKey fromJson(Map<String, dynamic> json) {
+  static ByValueKey fromJson(Map<String, dynamic> json) {
     String keyValueString = json['keyValueString'];
     String keyValueType = json['keyValueType'];
     switch(keyValueType) {
       case 'int':
-        return new FindByValueKey(int.parse(keyValueString));
+        return new ByValueKey(int.parse(keyValueString));
       case 'String':
-        return new FindByValueKey(keyValueString);
+        return new ByValueKey(keyValueString);
       default:
         return _throwInvalidKeyValueType(keyValueType);
     }

packages/flutter_driver/lib/src/retry.dart

@@ -8,13 +8,17 @@ import 'dart:async';
 /// that evaluates to the result.
 typedef dynamic Action();
 
+/// Determines if [value] is acceptable. For good style an implementation should
+/// be idempotent.
+typedef bool Predicate(dynamic value);
+
 /// Performs [action] repeatedly until it either succeeds or [timeout] limit is
 /// reached.
 ///
 /// When the retry time out, the last seen error and stack trace are returned in
 /// an error [Future].
 Future<dynamic> retry(Action action, Duration timeout,
-    Duration pauseBetweenRetries) async {
+    Duration pauseBetweenRetries, { Predicate predicate }) async {
   assert(action != null);
   assert(timeout != null);
   assert(pauseBetweenRetries != null);
@@ -28,20 +32,25 @@ Future<dynamic> retry(Action action, Duration timeout,
   while(!success && sw.elapsed < timeout) {
     try {
       result = await action();
-      success = true;
+      if (predicate == null || predicate(result))
+        success = true;
+      lastError = null;
+      lastStackTrace = null;
     } catch(error, stackTrace) {
       lastError = error;
       lastStackTrace = stackTrace;
-      if (sw.elapsed < timeout) {
-        await new Future<Null>.delayed(pauseBetweenRetries);
-      }
     }
+
+    if (!success && sw.elapsed < timeout)
+      await new Future<Null>.delayed(pauseBetweenRetries);
   }
 
   if (success)
     return result;
-  else
+  else if (lastError != null)
     return new Future.error(lastError, lastStackTrace);
+  else
+    return new Future.error('Retry timed out');
 }
 
 /// A function that produces a [Stopwatch].

packages/flutter_driver/test/flutter_driver_test.dart

@@ -122,9 +122,10 @@ main() {
       test('finds by ValueKey', () async {
         when(mockIsolate.invokeExtension(any, any)).thenAnswer((Invocation i) {
           expect(i.positionalArguments[1], {
-            'kind': 'find_by_value_key',
+            'kind': 'find',
+            'searchSpecType': 'ByValueKey',
             'keyValueString': 'foo',
-            'keyValueType': 'String',
+            'keyValueType': 'String'
           });
           return new Future.value({
             'objectReferenceKey': '123',

packages/flutter_driver/test/retry_test.dart

@@ -51,6 +51,26 @@ main() {
       });
     });
 
+    test('obeys predicates', () {
+      fakeAsync.run((_) {
+        int retryCount = 0;
+
+        expect(
+          // The predicate requires that the returned value is 2, so we expect
+          // that `retry` keeps trying until the counter reaches 2.
+          retry(
+            () async => retryCount++,
+            new Duration(milliseconds: 30),
+            new Duration(milliseconds: 10),
+            predicate: (value) => value == 2
+          ),
+          completion(2)
+        );
+
+        fakeAsync.elapse(new Duration(milliseconds: 50));
+      });
+    });
+
     test('times out returning last error', () async {
       fakeAsync.run((_) {
         bool timedOut = false;

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

@@ -55,6 +55,20 @@ bool _addPackage(String directoryPath, List<String> dartFiles, Set<String> pubSp
     }
   }
 
+  Directory testDriverDirectory = new Directory(path.join(directoryPath, 'test_driver'));
+  if (testDriverDirectory.existsSync()) {
+    for (FileSystemEntity entry in testDriverDirectory.listSync()) {
+      if (entry is Directory) {
+        for (FileSystemEntity subentry in entry.listSync()) {
+          if (isDartTestFile(subentry))
+            dartFiles.add(subentry.path);
+        }
+      } else if (isDartTestFile(entry)) {
+        dartFiles.add(entry.path);
+      }
+    }
+  }
+
   Directory benchmarkDirectory = new Directory(path.join(directoryPath, 'benchmark'));
   if (benchmarkDirectory.existsSync()) {
     for (FileSystemEntity entry in benchmarkDirectory.listSync()) {
@@ -76,6 +90,18 @@ bool _addPackage(String directoryPath, List<String> dartFiles, Set<String> pubSp
   return false;
 }
 
+/// Adds all packages in [subPath], assuming a flat directory structure, i.e.
+/// each direct child of [subPath] is a plain Dart package.
+void _addFlatPackageList(String subPath, List<String> dartFiles, Set<String> pubSpecDirectories) {
+  Directory subdirectory = new Directory(path.join(ArtifactStore.flutterRoot, subPath));
+  if (subdirectory.existsSync()) {
+    for (FileSystemEntity entry in subdirectory.listSync()) {
+      if (entry is Directory)
+        _addPackage(entry.path, dartFiles, pubSpecDirectories);
+    }
+  }
+}
+
 class FileChanged { }
 
 class AnalyzeCommand extends FlutterCommand {
@@ -146,23 +172,10 @@ class AnalyzeCommand extends FlutterCommand {
       //dev/manual_tests/*/ as package
       //dev/manual_tests/*/ as files
 
-      Directory subdirectory;
-
-      subdirectory = new Directory(path.join(ArtifactStore.flutterRoot, 'packages'));
-      if (subdirectory.existsSync()) {
-        for (FileSystemEntity entry in subdirectory.listSync()) {
-          if (entry is Directory)
-            _addPackage(entry.path, dartFiles, pubSpecDirectories);
-        }
-      }
+      _addFlatPackageList('packages', dartFiles, pubSpecDirectories);
+      _addFlatPackageList('examples', dartFiles, pubSpecDirectories);
 
-      subdirectory = new Directory(path.join(ArtifactStore.flutterRoot, 'examples'));
-      if (subdirectory.existsSync()) {
-        for (FileSystemEntity entry in subdirectory.listSync()) {
-          if (entry is Directory)
-            _addPackage(entry.path, dartFiles, pubSpecDirectories);
-        }
-      }
+      Directory subdirectory;
 
       subdirectory = new Directory(path.join(ArtifactStore.flutterRoot, 'examples', 'layers'));
       if (subdirectory.existsSync()) {
@@ -198,7 +211,7 @@ class AnalyzeCommand extends FlutterCommand {
 
     }
 
-    dartFiles = dartFiles.map((String directory) => path.normalize(path.absolute(directory))).toSet().toList();    
+    dartFiles = dartFiles.map((String directory) => path.normalize(path.absolute(directory))).toSet().toList();
     dartFiles.sort();
 
     // prepare a Dart file that references all the above Dart files
@@ -444,4 +457,3 @@ linter:
     return 0;
   }
 }
-

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

@@ -118,7 +118,7 @@ class DriveCommand extends RunCommandBase {
           await appStopper(this);
         } catch(error, stackTrace) {
           // TODO(yjbanov): remove this guard when this bug is fixed: https://github.com/dart-lang/sdk/issues/25862
-          printStatus('Could not stop application: $error\n$stackTrace');
+          printTrace('Could not stop application: $error\n$stackTrace');
         }
       } else {
         printStatus('Leaving the application running.');

packages/flutter_tools/templates/create/lib/main.dart.tmpl

 import 'package:flutter/material.dart';
+{{#withDriverTest?}}
+import 'package:flutter_driver/driver_extension.dart';
+{{/withDriverTest?}}
 
 void main() {
+{{#withDriverTest?}}
+  // Starts the app with Flutter Driver extension enabled to allow Flutter Driver
+  // to test the app.
+  enableFlutterDriverExtension();
+{{/withDriverTest?}}
   runApp(
     new MaterialApp(
       title: 'Flutter Demo',

packages/flutter_tools/templates/driver/e2e.dart.tmpl

-// Starts the app with Flutter Driver extension enabled to allow Flutter Driver
-// to test the app.
-import 'package:{{projectName}}/main.dart' as app;
-import 'package:flutter_driver/driver_extension.dart';
-
-main() {
-  enableFlutterDriverExtension();
-  app.main();
-}

packages/flutter_tools/templates/driver/e2e_test.dart.tmpl → packages/flutter_tools/templates/driver/main_test.dart.tmpl

@@ -22,28 +22,20 @@ main() {
     });
 
     tearDownAll(() async {
-      if (driver != null) driver.close();
-    });
-
-    test('find the floating action button by value key', () async {
-      ObjectRef elem = await driver.findByValueKey('fab');
-      expect(elem, isNotNull);
-      expect(elem.objectReferenceKey, isNotNull);
+      if (driver != null)
+        driver.close();
     });
 
     test('tap on the floating action button; verify counter', () async {
       // Find floating action button (fab) to tap on
-      ObjectRef fab = await driver.findByValueKey('fab');
+      ObjectRef fab = await driver.findByTooltipMessage('Increment');
       expect(fab, isNotNull);
 
       // Tap on the fab
       await driver.tap(fab);
 
       // Wait for text to change to the desired value
-      await driver.waitFor(() async {
-        ObjectRef counter = await driver.findByValueKey('counter');
-        return await driver.getText(counter);
-      }, contains("Button tapped 1 times."));
+      expect(await driver.findByText('Button tapped 1 time.'), isNotNull);
     });
   });
 }