extract flutter watch from flutter analyze (#6012)

dev/bots/test.sh

@@ -45,7 +45,7 @@ SRC_ROOT=$PWD
 
 # generate and analyze our large sample app
 dart dev/tools/mega_gallery.dart
-(cd dev/benchmarks/mega_gallery; flutter analyze --watch --benchmark)
+(cd dev/benchmarks/mega_gallery; flutter watch --benchmark)
 
 if [ -n "$COVERAGE_FLAG" ]; then
   GSUTIL=$HOME/google-cloud-sdk/bin/gsutil

packages/flutter_tools/lib/executable.dart

@@ -38,6 +38,7 @@ import 'src/commands/test.dart';
 import 'src/commands/trace.dart';
 import 'src/commands/update_packages.dart';
 import 'src/commands/upgrade.dart';
+import 'src/commands/watch.dart';
 import 'src/device.dart';
 import 'src/doctor.dart';
 import 'src/globals.dart';
@@ -84,7 +85,8 @@ Future<Null> main(List<String> args) async {
     ..addCommand(new TestCommand())
     ..addCommand(new TraceCommand())
     ..addCommand(new UpdatePackagesCommand(hidden: !verboseHelp))
-    ..addCommand(new UpgradeCommand());
+    ..addCommand(new UpgradeCommand())
+    ..addCommand(new WatchCommand(verboseHelp: verboseHelp));
 
   return Chain.capture/*<Future<Null>>*/(() async {
     // Initialize globals.

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

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:io';
+
+import '../base/utils.dart';
+import '../globals.dart';
+import '../runner/flutter_command.dart';
+
+/// Common behavior for `flutter analyze` and `flutter watch`
+abstract class AnalysisCommand extends FlutterCommand {
+  AnalysisCommand({bool verboseHelp: false}) {
+    argParser.addFlag('flutter-repo', help: 'Include all the examples and tests from the Flutter repository.', defaultsTo: false);
+    argParser.addFlag('current-directory', help: 'Include all the Dart files in the current directory, if any.', defaultsTo: true);
+    argParser.addFlag('current-package', help: 'Include the lib/main.dart file from the current directory, if any.', defaultsTo: true);
+    argParser.addFlag('dartdocs', help: 'List every public member that is lacking documentation (only examines files in the Flutter repository).', defaultsTo: false);
+    argParser.addOption('write', valueHelp: 'file', help: 'Also output the results to a file.');
+    argParser.addOption('dart-sdk', valueHelp: 'path-to-sdk', help: 'The path to the Dart SDK.', hide: !verboseHelp);
+
+    // Hidden option to enable a benchmarking mode.
+    argParser.addFlag('benchmark', negatable: false, hide: !verboseHelp, help: 'Also output the analysis time');
+
+    usesPubOption();
+  }
+
+  @override
+  bool get shouldRunPub {
+    // If they're not analyzing the current project.
+    if (!argResults['current-package'])
+      return false;
+
+    // Or we're not in a project directory.
+    if (!new File('pubspec.yaml').existsSync())
+      return false;
+
+    return super.shouldRunPub;
+  }
+
+  void dumpErrors(Iterable<String> errors) {
+    if (argResults['write'] != null) {
+      try {
+        final RandomAccessFile resultsFile = new File(argResults['write']).openSync(mode: FileMode.WRITE);
+        try {
+          resultsFile.lockSync();
+          resultsFile.writeStringSync(errors.join('\n'));
+        } finally {
+          resultsFile.close();
+        }
+      } catch (e) {
+        printError('Failed to save output to "${argResults['write']}": $e');
+      }
+    }
+  }
+
+  void writeBenchmark(Stopwatch stopwatch, int errorCount, int membersMissingDocumentation) {
+    final String benchmarkOut = 'analysis_benchmark.json';
+    Map<String, dynamic> data = <String, dynamic>{
+      'time': (stopwatch.elapsedMilliseconds / 1000.0),
+      'issues': errorCount,
+      'missingDartDocs': membersMissingDocumentation
+    };
+    new File(benchmarkOut).writeAsStringSync(toPrettyJson(data));
+    printStatus('Analysis benchmark written to $benchmarkOut ($data).');
+  }
+
+  bool get isBenchmarking => argResults['benchmark'];
+}
\ No newline at end of file

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

@@ -4,40 +4,24 @@
 
 import 'dart:async';
 import 'dart:collection';
-import 'dart:convert';
 import 'dart:io';
 
 import 'package:path/path.dart' as path;
 import 'package:yaml/yaml.dart' as yaml;
 
-import '../base/logger.dart';
-import '../base/utils.dart';
 import '../cache.dart';
 import '../dart/analysis.dart';
-import '../dart/sdk.dart';
 import '../globals.dart';
-import '../runner/flutter_command.dart';
+import 'analysis_common.dart';
 
 bool isDartFile(FileSystemEntity entry) => entry is File && entry.path.endsWith('.dart');
 
 typedef bool FileFilter(FileSystemEntity entity);
 
-class AnalyzeCommand extends FlutterCommand {
-  AnalyzeCommand({bool verboseHelp: false}) {
-    argParser.addFlag('flutter-repo', help: 'Include all the examples and tests from the Flutter repository.', defaultsTo: false);
-    argParser.addFlag('current-directory', help: 'Include all the Dart files in the current directory, if any.', defaultsTo: true);
-    argParser.addFlag('current-package', help: 'Include the lib/main.dart file from the current directory, if any.', defaultsTo: true);
-    argParser.addFlag('dartdocs', help: 'List every public member that is lacking documentation (only examines files in the Flutter repository).', defaultsTo: false);
-    argParser.addFlag('preamble', help: 'Display the number of files that will be analyzed.', defaultsTo: true);
+class AnalyzeCommand extends AnalysisCommand {
+  AnalyzeCommand({bool verboseHelp: false}) : super(verboseHelp: verboseHelp) {
     argParser.addFlag('congratulate', help: 'Show output even when there are no errors, warnings, hints, or lints.', defaultsTo: true);
-    argParser.addFlag('watch', help: 'Run analysis continuously, watching the filesystem for changes.', negatable: false);
-    argParser.addOption('write', valueHelp: 'file', help: 'Also output the results to a file. This is useful with --watch if you want a file to always contain the latest results.');
-    argParser.addOption('dart-sdk', valueHelp: 'path-to-sdk', help: 'The path to the Dart SDK.', hide: !verboseHelp);
-
-    // Hidden option to enable a benchmarking mode.
-    argParser.addFlag('benchmark', negatable: false, hide: !verboseHelp);
-
-    usesPubOption();
+    argParser.addFlag('preamble', help: 'Display the number of files that will be analyzed.', defaultsTo: true);
   }
 
   @override
@@ -47,58 +31,7 @@ class AnalyzeCommand extends FlutterCommand {
   String get description => 'Analyze the project\'s Dart code.';
 
   @override
-  bool get shouldRunPub {
-    // If they're not analyzing the current project.
-    if (!argResults['current-package'])
-      return false;
-
-    // Or we're not in a project directory.
-    if (!new File('pubspec.yaml').existsSync())
-      return false;
-
-    return super.shouldRunPub;
-  }
-
-  @override
-  Future<int> runCommand() => argResults['watch'] ? _analyzeWatch() : _analyzeOnce();
-
-  List<String> flutterRootComponents;
-  bool isFlutterLibrary(String filename) {
-    flutterRootComponents ??= path.normalize(path.absolute(Cache.flutterRoot)).split(path.separator);
-    List<String> filenameComponents = path.normalize(path.absolute(filename)).split(path.separator);
-    if (filenameComponents.length < flutterRootComponents.length + 4) // the 4: 'packages', package_name, 'lib', file_name
-      return false;
-    for (int index = 0; index < flutterRootComponents.length; index += 1) {
-      if (flutterRootComponents[index] != filenameComponents[index])
-        return false;
-    }
-    if (filenameComponents[flutterRootComponents.length] != 'packages')
-      return false;
-    if (filenameComponents[flutterRootComponents.length + 1] == 'flutter_tools')
-      return false;
-    if (filenameComponents[flutterRootComponents.length + 2] != 'lib')
-      return false;
-    return true;
-  }
-
-  /// Return `true` if [fileList] contains a path that resides inside the Flutter repository.
-  /// If [fileList] is empty, then return `true` if the current directory resides inside the Flutter repository.
-  bool inRepo(List<String> fileList) {
-    if (fileList == null || fileList.isEmpty)
-      fileList = <String>[path.current];
-    String root = path.normalize(path.absolute(Cache.flutterRoot));
-    String prefix = root + Platform.pathSeparator;
-    for (String file in fileList) {
-      file = path.normalize(path.absolute(file));
-      if (file == root || file.startsWith(prefix))
-        return true;
-    }
-    return false;
-  }
-
-  bool get _isBenchmarking => argResults['benchmark'];
-
-  Future<int> _analyzeOnce() async {
+  Future<int> runCommand() async {
     Stopwatch stopwatch = new Stopwatch()..start();
     Set<Directory> pubSpecDirectories = new HashSet<Directory>();
     List<File> dartFiles = <File>[];
@@ -188,7 +121,7 @@ class AnalyzeCommand extends FlutterCommand {
               if (packageName != 'analyzer' || packagePath.startsWith('..'))
                 dependencies.add(packageName, path.normalize(path.absolute(directory.path, path.fromUri(packagePath))), dotPackagesPath);
             }
-          });
+        });
       }
     }
 
@@ -216,8 +149,8 @@ class AnalyzeCommand extends FlutterCommand {
     options.dartSdkPath = argResults['dart-sdk'];
     options.packageMap = packages;
     options.analysisOptionsFile = flutterRepo
-      ? path.join(Cache.flutterRoot, '.analysis_options_repo')
-      : path.join(Cache.flutterRoot, '.analysis_options_user');
+        ? path.join(Cache.flutterRoot, '.analysis_options_repo')
+        : path.join(Cache.flutterRoot, '.analysis_options_user');
     AnalysisDriver analyzer = new AnalysisDriver(options);
 
     // TODO(pq): consider error handling
@@ -247,13 +180,13 @@ class AnalyzeCommand extends FlutterCommand {
       printError(error.asString());
       errorCount += 1;
     }
-    _dumpErrors(errors.map/*<String>*/((AnalysisErrorDescription error) => error.asString()));
+    dumpErrors(errors.map/*<String>*/((AnalysisErrorDescription error) => error.asString()));
 
     stopwatch.stop();
     String elapsed = (stopwatch.elapsedMilliseconds / 1000.0).toStringAsFixed(1);
 
-    if (_isBenchmarking)
-      _writeBenchmark(stopwatch, errorCount, membersMissingDocumentation);
+    if (isBenchmarking)
+      writeBenchmark(stopwatch, errorCount, membersMissingDocumentation);
 
     if (errorCount > 0) {
       if (membersMissingDocumentation > 0 && flutterRepo)
@@ -272,20 +205,38 @@ class AnalyzeCommand extends FlutterCommand {
     return 0;
   }
 
-  void _dumpErrors(Iterable<String> errors) {
-    if (argResults['write'] != null) {
-      try {
-        final RandomAccessFile resultsFile = new File(argResults['write']).openSync(mode: FileMode.WRITE);
-        try {
-          resultsFile.lockSync();
-          resultsFile.writeStringSync(errors.join('\n'));
-        } finally {
-          resultsFile.close();
-        }
-      } catch (e) {
-        printError('Failed to save output to "${argResults['write']}": $e');
-      }
+  List<String> flutterRootComponents;
+  bool isFlutterLibrary(String filename) {
+    flutterRootComponents ??= path.normalize(path.absolute(Cache.flutterRoot)).split(path.separator);
+    List<String> filenameComponents = path.normalize(path.absolute(filename)).split(path.separator);
+    if (filenameComponents.length < flutterRootComponents.length + 4) // the 4: 'packages', package_name, 'lib', file_name
+      return false;
+    for (int index = 0; index < flutterRootComponents.length; index += 1) {
+      if (flutterRootComponents[index] != filenameComponents[index])
+        return false;
     }
+    if (filenameComponents[flutterRootComponents.length] != 'packages')
+      return false;
+    if (filenameComponents[flutterRootComponents.length + 1] == 'flutter_tools')
+      return false;
+    if (filenameComponents[flutterRootComponents.length + 2] != 'lib')
+      return false;
+    return true;
+  }
+
+  /// Return `true` if [fileList] contains a path that resides inside the Flutter repository.
+  /// If [fileList] is empty, then return `true` if the current directory resides inside the Flutter repository.
+  bool inRepo(List<String> fileList) {
+    if (fileList == null || fileList.isEmpty)
+      fileList = <String>[path.current];
+    String root = path.normalize(path.absolute(Cache.flutterRoot));
+    String prefix = root + Platform.pathSeparator;
+    for (String file in fileList) {
+      file = path.normalize(path.absolute(file));
+      if (file == root || file.startsWith(prefix))
+        return true;
+    }
+    return false;
   }
 
   List<File> _collectDartFiles(Directory dir, List<File> collected, {FileFilter exclude}) {
@@ -305,134 +256,6 @@ class AnalyzeCommand extends FlutterCommand {
 
     return collected;
   }
-
-
-  String analysisTarget;
-  bool firstAnalysis = true;
-  Set<String> analyzedPaths = new Set<String>();
-  Map<String, List<AnalysisError>> analysisErrors = <String, List<AnalysisError>>{};
-  Stopwatch analysisTimer;
-  int lastErrorCount = 0;
-  Status analysisStatus;
-
-  Future<int> _analyzeWatch() async {
-    List<String> directories;
-
-    if (argResults['flutter-repo']) {
-      directories = runner.getRepoAnalysisEntryPoints().map((Directory dir) => dir.path).toList();
-      analysisTarget = 'Flutter repository';
-      printTrace('Analyzing Flutter repository:');
-      for (String projectPath in directories)
-        printTrace('  ${path.relative(projectPath)}');
-    } else {
-      directories = <String>[Directory.current.path];
-      analysisTarget = Directory.current.path;
-    }
-
-    AnalysisServer server = new AnalysisServer(dartSdkPath, directories);
-    server.onAnalyzing.listen((bool isAnalyzing) => _handleAnalysisStatus(server, isAnalyzing));
-    server.onErrors.listen(_handleAnalysisErrors);
-
-    Cache.releaseLockEarly();
-
-    await server.start();
-    final int exitCode = await server.onExit;
-
-    printStatus('Analysis server exited with code $exitCode.');
-    return 0;
-  }
-
-  void _handleAnalysisStatus(AnalysisServer server, bool isAnalyzing) {
-    if (isAnalyzing) {
-      analysisStatus?.cancel();
-      if (!firstAnalysis)
-        printStatus('\n');
-      analysisStatus = logger.startProgress('Analyzing $analysisTarget...');
-      analyzedPaths.clear();
-      analysisTimer = new Stopwatch()..start();
-    } else {
-      analysisStatus?.stop(showElapsedTime: true);
-      analysisTimer.stop();
-
-      logger.printStatus(terminal.clearScreen(), newline: false);
-
-      // Remove errors for deleted files, sort, and print errors.
-      final List<AnalysisError> errors = <AnalysisError>[];
-      for (String path in analysisErrors.keys.toList()) {
-        if (FileSystemEntity.isFileSync(path)) {
-          errors.addAll(analysisErrors[path]);
-        } else {
-          analysisErrors.remove(path);
-        }
-      }
-
-      errors.sort();
-
-      for (AnalysisError error in errors) {
-        printStatus(error.toString());
-        if (error.code != null)
-          printTrace('error code: ${error.code}');
-      }
-
-      _dumpErrors(errors.map/*<String>*/((AnalysisError error) => error.toLegacyString()));
-
-      // Print an analysis summary.
-      String errorsMessage;
-
-      int issueCount = errors.length;
-      int issueDiff = issueCount - lastErrorCount;
-      lastErrorCount = issueCount;
-
-      if (firstAnalysis)
-        errorsMessage = '$issueCount ${pluralize('issue', issueCount)} found';
-      else if (issueDiff > 0)
-        errorsMessage = '$issueCount ${pluralize('issue', issueCount)} found ($issueDiff new)';
-      else if (issueDiff < 0)
-        errorsMessage = '$issueCount ${pluralize('issue', issueCount)} found (${-issueDiff} fixed)';
-      else if (issueCount != 0)
-        errorsMessage = '$issueCount ${pluralize('issue', issueCount)} found';
-      else
-        errorsMessage = 'no issues found';
-
-      String files = '${analyzedPaths.length} ${pluralize('file', analyzedPaths.length)}';
-      String seconds = (analysisTimer.elapsedMilliseconds / 1000.0).toStringAsFixed(2);
-      printStatus('$errorsMessage • analyzed $files, $seconds seconds');
-
-      if (firstAnalysis && _isBenchmarking) {
-        _writeBenchmark(analysisTimer, issueCount, -1); // TODO(ianh): track members missing dartdocs instead of saying -1
-        server.dispose().then((_) => exit(issueCount > 0 ? 1 : 0));
-      }
-
-      firstAnalysis = false;
-    }
-  }
-
-  void _handleAnalysisErrors(FileAnalysisErrors fileErrors) {
-    fileErrors.errors.removeWhere(_filterError);
-
-    analyzedPaths.add(fileErrors.file);
-    analysisErrors[fileErrors.file] = fileErrors.errors;
-  }
-
-  bool _filterError(AnalysisError error) {
-    // TODO(devoncarew): Also filter the regex items from `analyzeOnce()`.
-
-    if (error.type == 'TODO')
-      return true;
-
-    return false;
-  }
-
-  void _writeBenchmark(Stopwatch stopwatch, int errorCount, int membersMissingDocumentation) {
-    final String benchmarkOut = 'analysis_benchmark.json';
-    Map<String, dynamic> data = <String, dynamic>{
-      'time': (stopwatch.elapsedMilliseconds / 1000.0),
-      'issues': errorCount,
-      'missingDartDocs': membersMissingDocumentation
-    };
-    new File(benchmarkOut).writeAsStringSync(toPrettyJson(data));
-    printStatus('Analysis benchmark written to $benchmarkOut ($data).');
-  }
 }
 
 class PackageDependency {
@@ -523,179 +346,3 @@ class PackageDependencyTracker {
     return result;
   }
 }
-
-class AnalysisServer {
-  AnalysisServer(this.sdk, this.directories);
-
-  final String sdk;
-  final List<String> directories;
-
-  Process _process;
-  StreamController<bool> _analyzingController = new StreamController<bool>.broadcast();
-  StreamController<FileAnalysisErrors> _errorsController = new StreamController<FileAnalysisErrors>.broadcast();
-
-  int _id = 0;
-
-  Future<Null> start() async {
-    String snapshot = path.join(sdk, 'bin/snapshots/analysis_server.dart.snapshot');
-    List<String> args = <String>[snapshot, '--sdk', sdk];
-
-    printTrace('dart ${args.join(' ')}');
-    _process = await Process.start(path.join(dartSdkPath, 'bin', 'dart'), args);
-    _process.exitCode.whenComplete(() => _process = null);
-
-    Stream<String> errorStream = _process.stderr.transform(UTF8.decoder).transform(const LineSplitter());
-    errorStream.listen((String error) => printError(error));
-
-    Stream<String> inStream = _process.stdout.transform(UTF8.decoder).transform(const LineSplitter());
-    inStream.listen(_handleServerResponse);
-
-    // Available options (many of these are obsolete):
-    //   enableAsync, enableDeferredLoading, enableEnums, enableNullAwareOperators,
-    //   enableSuperMixins, generateDart2jsHints, generateHints, generateLints
-    _sendCommand('analysis.updateOptions', <String, dynamic>{
-      'options': <String, dynamic>{
-        'enableSuperMixins': true
-      }
-    });
-
-    _sendCommand('server.setSubscriptions', <String, dynamic>{
-      'subscriptions': <String>['STATUS']
-    });
-
-    _sendCommand('analysis.setAnalysisRoots', <String, dynamic>{
-      'included': directories,
-      'excluded': <String>[]
-    });
-  }
-
-  Stream<bool> get onAnalyzing => _analyzingController.stream;
-  Stream<FileAnalysisErrors> get onErrors => _errorsController.stream;
-
-  Future<int> get onExit => _process.exitCode;
-
-  void _sendCommand(String method, Map<String, dynamic> params) {
-    String message = JSON.encode(<String, dynamic> {
-      'id': (++_id).toString(),
-      'method': method,
-      'params': params
-    });
-    _process.stdin.writeln(message);
-    printTrace('==> $message');
-  }
-
-  void _handleServerResponse(String line) {
-    printTrace('<== $line');
-
-    dynamic response = JSON.decode(line);
-
-    if (response is Map<dynamic, dynamic>) {
-      if (response['event'] != null) {
-        String event = response['event'];
-        dynamic params = response['params'];
-
-        if (params is Map<dynamic, dynamic>) {
-          if (event == 'server.status')
-            _handleStatus(response['params']);
-          else if (event == 'analysis.errors')
-            _handleAnalysisIssues(response['params']);
-          else if (event == 'server.error')
-            _handleServerError(response['params']);
-        }
-      } else if (response['error'] != null) {
-        // Fields are 'code', 'message', and 'stackTrace'.
-        Map<String, dynamic> error = response['error'];
-        printError('Error response from the server: ${error['code']} ${error['message']}');
-        if (error['stackTrace'] != null)
-          printError(error['stackTrace']);
-      }
-    }
-  }
-
-  void _handleStatus(Map<String, dynamic> statusInfo) {
-    // {"event":"server.status","params":{"analysis":{"isAnalyzing":true}}}
-    if (statusInfo['analysis'] != null) {
-      bool isAnalyzing = statusInfo['analysis']['isAnalyzing'];
-      _analyzingController.add(isAnalyzing);
-    }
-  }
-
-  void _handleServerError(Map<String, dynamic> error) {
-    // Fields are 'isFatal', 'message', and 'stackTrace'.
-    printError('Error from the analysis server: ${error['message']}');
-    if (error['stackTrace'] != null)
-      printError(error['stackTrace']);
-  }
-
-  void _handleAnalysisIssues(Map<String, dynamic> issueInfo) {
-    // {"event":"analysis.errors","params":{"file":"/Users/.../lib/main.dart","errors":[]}}
-    String file = issueInfo['file'];
-    List<AnalysisError> errors = issueInfo['errors'].map((Map<String, dynamic> json) => new AnalysisError(json)).toList();
-    _errorsController.add(new FileAnalysisErrors(file, errors));
-  }
-
-  Future<bool> dispose() async {
-    await _analyzingController.close();
-    await _errorsController.close();
-    return _process?.kill();
-  }
-}
-
-class FileAnalysisErrors {
-  FileAnalysisErrors(this.file, this.errors);
-
-  final String file;
-  final List<AnalysisError> errors;
-}
-
-class AnalysisError implements Comparable<AnalysisError> {
-  AnalysisError(this.json);
-
-  static final Map<String, int> _severityMap = <String, int> {
-    'ERROR': 3,
-    'WARNING': 2,
-    'INFO': 1
-  };
-
-  // "severity":"INFO","type":"TODO","location":{
-  //   "file":"/Users/.../lib/test.dart","offset":362,"length":72,"startLine":15,"startColumn":4
-  // },"message":"...","hasFix":false}
-  Map<String, dynamic> json;
-
-  String get severity => json['severity'];
-  int get severityLevel => _severityMap[severity] ?? 0;
-  String get type => json['type'];
-  String get message => json['message'];
-  String get code => json['code'];
-
-  String get file => json['location']['file'];
-  int get startLine => json['location']['startLine'];
-  int get startColumn => json['location']['startColumn'];
-  int get offset => json['location']['offset'];
-
-  @override
-  int compareTo(AnalysisError other) {
-    // Sort in order of file path, error location, severity, and message.
-    if (file != other.file)
-      return file.compareTo(other.file);
-
-    if (offset != other.offset)
-      return offset - other.offset;
-
-    int diff = other.severityLevel - severityLevel;
-    if (diff != 0)
-      return diff;
-
-    return message.compareTo(other.message);
-  }
-
-  @override
-  String toString() {
-    String relativePath = path.relative(file);
-    return '${severity.toLowerCase().padLeft(7)} • $message • $relativePath:$startLine:$startColumn';
-  }
-
-  String toLegacyString() {
-    return '[${severity.toLowerCase()}] $message ($file:$startLine:$startColumn)';
-  }
-}

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

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:path/path.dart' as path;
+
+import '../base/logger.dart';
+import '../base/utils.dart';
+import '../cache.dart';
+import '../dart/sdk.dart';
+import '../globals.dart';
+import 'analysis_common.dart';
+
+class WatchCommand extends AnalysisCommand {
+  WatchCommand({bool verboseHelp: false}) : super(verboseHelp: verboseHelp);
+
+  @override
+  String get name => 'watch';
+
+  @override
+  String get description => 'Analyze the project\'s Dart code continuously, watching the filesystem for changes.';
+
+  String analysisTarget;
+  bool firstAnalysis = true;
+  Set<String> analyzedPaths = new Set<String>();
+  Map<String, List<AnalysisError>> analysisErrors = <String, List<AnalysisError>>{};
+  Stopwatch analysisTimer;
+  int lastErrorCount = 0;
+  Status analysisStatus;
+
+  @override
+  Future<int> runCommand() async {
+    List<String> directories;
+
+    if (argResults['flutter-repo']) {
+      directories = runner.getRepoAnalysisEntryPoints().map((Directory dir) => dir.path).toList();
+      analysisTarget = 'Flutter repository';
+      printTrace('Analyzing Flutter repository:');
+      for (String projectPath in directories)
+        printTrace('  ${path.relative(projectPath)}');
+    } else {
+      directories = <String>[Directory.current.path];
+      analysisTarget = Directory.current.path;
+    }
+
+    AnalysisServer server = new AnalysisServer(dartSdkPath, directories);
+    server.onAnalyzing.listen((bool isAnalyzing) => _handleAnalysisStatus(server, isAnalyzing));
+    server.onErrors.listen(_handleAnalysisErrors);
+
+    Cache.releaseLockEarly();
+
+    await server.start();
+    final int exitCode = await server.onExit;
+
+    printStatus('Analysis server exited with code $exitCode.');
+    return 0;
+  }
+
+  void _handleAnalysisStatus(AnalysisServer server, bool isAnalyzing) {
+    if (isAnalyzing) {
+      analysisStatus?.cancel();
+      if (!firstAnalysis)
+        printStatus('\n');
+      analysisStatus = logger.startProgress('Analyzing $analysisTarget...');
+      analyzedPaths.clear();
+      analysisTimer = new Stopwatch()..start();
+    } else {
+      analysisStatus?.stop(showElapsedTime: true);
+      analysisTimer.stop();
+
+      logger.printStatus(terminal.clearScreen(), newline: false);
+
+      // Remove errors for deleted files, sort, and print errors.
+      final List<AnalysisError> errors = <AnalysisError>[];
+      for (String path in analysisErrors.keys.toList()) {
+        if (FileSystemEntity.isFileSync(path)) {
+          errors.addAll(analysisErrors[path]);
+        } else {
+          analysisErrors.remove(path);
+        }
+      }
+
+      errors.sort();
+
+      for (AnalysisError error in errors) {
+        printStatus(error.toString());
+        if (error.code != null)
+          printTrace('error code: ${error.code}');
+      }
+
+      dumpErrors(errors.map/*<String>*/((AnalysisError error) => error.toLegacyString()));
+
+      // Print an analysis summary.
+      String errorsMessage;
+
+      int issueCount = errors.length;
+      int issueDiff = issueCount - lastErrorCount;
+      lastErrorCount = issueCount;
+
+      if (firstAnalysis)
+        errorsMessage = '$issueCount ${pluralize('issue', issueCount)} found';
+      else if (issueDiff > 0)
+        errorsMessage = '$issueCount ${pluralize('issue', issueCount)} found ($issueDiff new)';
+      else if (issueDiff < 0)
+        errorsMessage = '$issueCount ${pluralize('issue', issueCount)} found (${-issueDiff} fixed)';
+      else if (issueCount != 0)
+        errorsMessage = '$issueCount ${pluralize('issue', issueCount)} found';
+      else
+        errorsMessage = 'no issues found';
+
+      String files = '${analyzedPaths.length} ${pluralize('file', analyzedPaths.length)}';
+      String seconds = (analysisTimer.elapsedMilliseconds / 1000.0).toStringAsFixed(2);
+      printStatus('$errorsMessage • analyzed $files, $seconds seconds');
+
+      if (firstAnalysis && isBenchmarking) {
+        writeBenchmark(analysisTimer, issueCount, -1); // TODO(ianh): track members missing dartdocs instead of saying -1
+        server.dispose().then((_) => exit(issueCount > 0 ? 1 : 0));
+      }
+
+      firstAnalysis = false;
+    }
+  }
+
+  bool _filterError(AnalysisError error) {
+    // TODO(devoncarew): Also filter the regex items from `analyzeOnce()`.
+
+    if (error.type == 'TODO')
+      return true;
+
+    return false;
+  }
+
+  void _handleAnalysisErrors(FileAnalysisErrors fileErrors) {
+    fileErrors.errors.removeWhere(_filterError);
+
+    analyzedPaths.add(fileErrors.file);
+    analysisErrors[fileErrors.file] = fileErrors.errors;
+  }
+}
+
+class AnalysisServer {
+  AnalysisServer(this.sdk, this.directories);
+
+  final String sdk;
+  final List<String> directories;
+
+  Process _process;
+  StreamController<bool> _analyzingController = new StreamController<bool>.broadcast();
+  StreamController<FileAnalysisErrors> _errorsController = new StreamController<FileAnalysisErrors>.broadcast();
+
+  int _id = 0;
+
+  Future<Null> start() async {
+    String snapshot = path.join(sdk, 'bin/snapshots/analysis_server.dart.snapshot');
+    List<String> args = <String>[snapshot, '--sdk', sdk];
+
+    printTrace('dart ${args.join(' ')}');
+    _process = await Process.start(path.join(dartSdkPath, 'bin', 'dart'), args);
+    _process.exitCode.whenComplete(() => _process = null);
+
+    Stream<String> errorStream = _process.stderr.transform(UTF8.decoder).transform(const LineSplitter());
+    errorStream.listen((String error) => printError(error));
+
+    Stream<String> inStream = _process.stdout.transform(UTF8.decoder).transform(const LineSplitter());
+    inStream.listen(_handleServerResponse);
+
+    // Available options (many of these are obsolete):
+    //   enableAsync, enableDeferredLoading, enableEnums, enableNullAwareOperators,
+    //   enableSuperMixins, generateDart2jsHints, generateHints, generateLints
+    _sendCommand('analysis.updateOptions', <String, dynamic>{
+      'options': <String, dynamic>{
+        'enableSuperMixins': true
+      }
+    });
+
+    _sendCommand('server.setSubscriptions', <String, dynamic>{
+      'subscriptions': <String>['STATUS']
+    });
+
+    _sendCommand('analysis.setAnalysisRoots', <String, dynamic>{
+      'included': directories,
+      'excluded': <String>[]
+    });
+  }
+
+  Stream<bool> get onAnalyzing => _analyzingController.stream;
+  Stream<FileAnalysisErrors> get onErrors => _errorsController.stream;
+
+  Future<int> get onExit => _process.exitCode;
+
+  void _sendCommand(String method, Map<String, dynamic> params) {
+    String message = JSON.encode(<String, dynamic> {
+      'id': (++_id).toString(),
+      'method': method,
+      'params': params
+    });
+    _process.stdin.writeln(message);
+    printTrace('==> $message');
+  }
+
+  void _handleServerResponse(String line) {
+    printTrace('<== $line');
+
+    dynamic response = JSON.decode(line);
+
+    if (response is Map<dynamic, dynamic>) {
+      if (response['event'] != null) {
+        String event = response['event'];
+        dynamic params = response['params'];
+
+        if (params is Map<dynamic, dynamic>) {
+          if (event == 'server.status')
+            _handleStatus(response['params']);
+          else if (event == 'analysis.errors')
+            _handleAnalysisIssues(response['params']);
+          else if (event == 'server.error')
+            _handleServerError(response['params']);
+        }
+      } else if (response['error'] != null) {
+        // Fields are 'code', 'message', and 'stackTrace'.
+        Map<String, dynamic> error = response['error'];
+        printError('Error response from the server: ${error['code']} ${error['message']}');
+        if (error['stackTrace'] != null)
+          printError(error['stackTrace']);
+      }
+    }
+  }
+
+  void _handleStatus(Map<String, dynamic> statusInfo) {
+    // {"event":"server.status","params":{"analysis":{"isAnalyzing":true}}}
+    if (statusInfo['analysis'] != null) {
+      bool isAnalyzing = statusInfo['analysis']['isAnalyzing'];
+      _analyzingController.add(isAnalyzing);
+    }
+  }
+
+  void _handleServerError(Map<String, dynamic> error) {
+    // Fields are 'isFatal', 'message', and 'stackTrace'.
+    printError('Error from the analysis server: ${error['message']}');
+    if (error['stackTrace'] != null)
+      printError(error['stackTrace']);
+  }
+
+  void _handleAnalysisIssues(Map<String, dynamic> issueInfo) {
+    // {"event":"analysis.errors","params":{"file":"/Users/.../lib/main.dart","errors":[]}}
+    String file = issueInfo['file'];
+    List<AnalysisError> errors = issueInfo['errors'].map((Map<String, dynamic> json) => new AnalysisError(json)).toList();
+    _errorsController.add(new FileAnalysisErrors(file, errors));
+  }
+
+  Future<bool> dispose() async {
+    await _analyzingController.close();
+    await _errorsController.close();
+    return _process?.kill();
+  }
+}
+
+class AnalysisError implements Comparable<AnalysisError> {
+  AnalysisError(this.json);
+
+  static final Map<String, int> _severityMap = <String, int> {
+    'ERROR': 3,
+    'WARNING': 2,
+    'INFO': 1
+  };
+
+  // "severity":"INFO","type":"TODO","location":{
+  //   "file":"/Users/.../lib/test.dart","offset":362,"length":72,"startLine":15,"startColumn":4
+  // },"message":"...","hasFix":false}
+  Map<String, dynamic> json;
+
+  String get severity => json['severity'];
+  int get severityLevel => _severityMap[severity] ?? 0;
+  String get type => json['type'];
+  String get message => json['message'];
+  String get code => json['code'];
+
+  String get file => json['location']['file'];
+  int get startLine => json['location']['startLine'];
+  int get startColumn => json['location']['startColumn'];
+  int get offset => json['location']['offset'];
+
+  @override
+  int compareTo(AnalysisError other) {
+    // Sort in order of file path, error location, severity, and message.
+    if (file != other.file)
+      return file.compareTo(other.file);
+
+    if (offset != other.offset)
+      return offset - other.offset;
+
+    int diff = other.severityLevel - severityLevel;
+    if (diff != 0)
+      return diff;
+
+    return message.compareTo(other.message);
+  }
+
+  @override
+  String toString() {
+    String relativePath = path.relative(file);
+    return '${severity.toLowerCase().padLeft(7)} • $message • $relativePath:$startLine:$startColumn';
+  }
+
+  String toLegacyString() {
+    return '[${severity.toLowerCase()}] $message ($file:$startLine:$startColumn)';
+  }
+}
+
+class FileAnalysisErrors {
+  FileAnalysisErrors(this.file, this.errors);
+
+  final String file;
+  final List<AnalysisError> errors;
+}

packages/flutter_tools/test/analyze_test.dart

@@ -2,14 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:async';
 import 'dart:io';
 
-import 'package:flutter_tools/src/base/os.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/commands/analyze.dart';
-import 'package:flutter_tools/src/dart/pub.dart';
-import 'package:flutter_tools/src/dart/sdk.dart';
 import 'package:flutter_tools/src/runner/flutter_command_runner.dart';
 import 'package:path/path.dart' as path;
 import 'package:test/test.dart';
@@ -17,7 +13,6 @@ import 'package:test/test.dart';
 import 'src/context.dart';
 
 void main() {
-  AnalysisServer server;
   Directory tempDir;
 
   setUp(() {
@@ -27,47 +22,9 @@ void main() {
 
   tearDown(() {
     tempDir?.deleteSync(recursive: true);
-    return server?.dispose();
   });
 
   group('analyze', () {
-    testUsingContext('AnalysisServer success', () async {
-      _createSampleProject(tempDir);
-
-      await pubGet(directory: tempDir.path);
-
-      server = new AnalysisServer(dartSdkPath, <String>[tempDir.path]);
-
-      int errorCount = 0;
-      Future<bool> onDone = server.onAnalyzing.where((bool analyzing) => analyzing == false).first;
-      server.onErrors.listen((FileAnalysisErrors errors) => errorCount += errors.errors.length);
-
-      await server.start();
-      await onDone;
-
-      expect(errorCount, 0);
-    }, overrides: <Type, dynamic>{
-      OperatingSystemUtils: os
-    });
-
-    testUsingContext('AnalysisServer errors', () async {
-      _createSampleProject(tempDir, brokenCode: true);
-
-      await pubGet(directory: tempDir.path);
-
-      server = new AnalysisServer(dartSdkPath, <String>[tempDir.path]);
-
-      int errorCount = 0;
-      Future<bool> onDone = server.onAnalyzing.where((bool analyzing) => analyzing == false).first;
-      server.onErrors.listen((FileAnalysisErrors errors) => errorCount += errors.errors.length);
-
-      await server.start();
-      await onDone;
-
-      expect(errorCount, 2);
-    }, overrides: <Type, dynamic>{
-      OperatingSystemUtils: os
-    });
 
     testUsingContext('inRepo', () {
       AnalyzeCommand cmd = new AnalyzeCommand();
@@ -94,19 +51,3 @@ void main() {
     });
   });
 }
-
-void _createSampleProject(Directory directory, { bool brokenCode: false }) {
-  File pubspecFile = new File(path.join(directory.path, 'pubspec.yaml'));
-  pubspecFile.writeAsStringSync('''
-name: foo_project
-''');
-
-  File dartFile = new File(path.join(directory.path, 'lib', 'main.dart'));
-  dartFile.parent.createSync();
-  dartFile.writeAsStringSync('''
-void main() {
-  print('hello world');
-  ${brokenCode ? 'prints("hello world");' : ''}
-}
-''');
-}

packages/flutter_tools/test/watch_test.dart

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:io';
+
+import 'package:flutter_tools/src/base/os.dart';
+import 'package:flutter_tools/src/commands/watch.dart';
+import 'package:flutter_tools/src/dart/pub.dart';
+import 'package:flutter_tools/src/dart/sdk.dart';
+import 'package:flutter_tools/src/runner/flutter_command_runner.dart';
+import 'package:path/path.dart' as path;
+import 'package:test/test.dart';
+
+import 'src/context.dart';
+
+void main() {
+  AnalysisServer server;
+  Directory tempDir;
+
+  setUp(() {
+    FlutterCommandRunner.initFlutterRoot();
+    tempDir = Directory.systemTemp.createTempSync('analysis_test');
+  });
+
+  tearDown(() {
+    tempDir?.deleteSync(recursive: true);
+    return server?.dispose();
+  });
+
+  group('watch', () {
+    testUsingContext('AnalysisServer success', () async {
+      _createSampleProject(tempDir);
+
+      await pubGet(directory: tempDir.path);
+
+      server = new AnalysisServer(dartSdkPath, <String>[tempDir.path]);
+
+      int errorCount = 0;
+      Future<bool> onDone = server.onAnalyzing.where((bool analyzing) => analyzing == false).first;
+      server.onErrors.listen((FileAnalysisErrors errors) => errorCount += errors.errors.length);
+
+      await server.start();
+      await onDone;
+
+      expect(errorCount, 0);
+    }, overrides: <Type, dynamic>{
+      OperatingSystemUtils: os
+    });
+  });
+
+  testUsingContext('AnalysisServer errors', () async {
+    _createSampleProject(tempDir, brokenCode: true);
+
+    await pubGet(directory: tempDir.path);
+
+    server = new AnalysisServer(dartSdkPath, <String>[tempDir.path]);
+
+    int errorCount = 0;
+    Future<bool> onDone = server.onAnalyzing.where((bool analyzing) => analyzing == false).first;
+    server.onErrors.listen((FileAnalysisErrors errors) => errorCount += errors.errors.length);
+
+    await server.start();
+    await onDone;
+
+    expect(errorCount, 2);
+  }, overrides: <Type, dynamic>{
+    OperatingSystemUtils: os
+  });
+}
+
+void _createSampleProject(Directory directory, { bool brokenCode: false }) {
+  File pubspecFile = new File(path.join(directory.path, 'pubspec.yaml'));
+  pubspecFile.writeAsStringSync('''
+name: foo_project
+''');
+
+  File dartFile = new File(path.join(directory.path, 'lib', 'main.dart'));
+  dartFile.parent.createSync();
+  dartFile.writeAsStringSync('''
+void main() {
+  print('hello world');
+  ${brokenCode ? 'prints("hello world");' : ''}
+}
+''');
+}