Revert "Revert "Use native async/await support in pub.""

sdk/lib/_internal/pub_generated/lib/src/barback/dart2js_transformer.dart

Index: sdk/lib/_internal/pub_generated/lib/src/barback/dart2js_transformer.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/barback/dart2js_transformer.dart b/sdk/lib/_internal/pub_generated/lib/src/barback/dart2js_transformer.dart
deleted file mode 100644
index 7fa94951acefe84b20927672b2179053ed0d1faa..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/lib/src/barback/dart2js_transformer.dart
+++ /dev/null
@@ -1,433 +0,0 @@
-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-library pub.dart2js_transformer;
-
-import 'dart:async';
-import 'dart:convert';
-
-import 'package:analyzer/analyzer.dart';
-import 'package:barback/barback.dart';
-import 'package:path/path.dart' as path;
-import 'package:pool/pool.dart';
-
-import '../../../../../../../pkg/compiler/lib/compiler.dart' as compiler;
-import '../../../../../../../pkg/compiler/lib/src/dart2js.dart' show AbortLeg;
-import '../../../../../../../pkg/compiler/lib/src/io/source_file.dart';
-import '../barback.dart';
-import '../dart.dart' as dart;
-import '../utils.dart';
-import 'asset_environment.dart';
-
-/// The set of all valid configuration options for this transformer.
-final _validOptions = new Set<String>.from(
-    [
-        'commandLineOptions',
-        'checked',
-        'csp',
-        'minify',
-        'verbose',
-        'environment',
-        'preserveUris',
-        'suppressWarnings',
-        'suppressHints',
-        'suppressPackageWarnings',
-        'terse',
-        'sourceMaps']);
-
-/// A [Transformer] that uses dart2js's library API to transform Dart
-/// entrypoints in "web" to JavaScript.
-class Dart2JSTransformer extends Transformer implements LazyTransformer {
-  /// We use this to ensure that only one compilation is in progress at a time.
-  ///
-  /// Dart2js uses lots of memory, so if we try to actually run compiles in
-  /// parallel, it takes down the VM. The tracking bug to do something better
-  /// is here: https://code.google.com/p/dart/issues/detail?id=14730.
-  static final _pool = new Pool(1);
-
-  final AssetEnvironment _environment;
-  final BarbackSettings _settings;
-
-  /// Whether source maps should be generated for the compiled JS.
-  bool get _generateSourceMaps =>
-      _configBool('sourceMaps', defaultsTo: _settings.mode != BarbackMode.RELEASE);
-
-  Dart2JSTransformer.withSettings(this._environment, this._settings) {
-    var invalidOptions =
-        _settings.configuration.keys.toSet().difference(_validOptions);
-    if (invalidOptions.isEmpty) return;
-
-    throw new FormatException(
-        "Unrecognized dart2js " "${pluralize('option', invalidOptions.length)} "
-            "${toSentence(invalidOptions.map((option) => '"$option"'))}.");
-  }
-
-  Dart2JSTransformer(AssetEnvironment environment, BarbackMode mode)
-      : this.withSettings(environment, new BarbackSettings({}, mode));
-
-  /// Only ".dart" entrypoint files within a buildable directory are processed.
-  bool isPrimary(AssetId id) {
-    if (id.extension != ".dart") return false;
-
-    // "lib" should only contain libraries. For efficiency's sake, we don't
-    // look for entrypoints in there.
-    return !id.path.startsWith("lib/");
-  }
-
-  Future apply(Transform transform) {
-    // TODO(nweiz): If/when barback starts reporting what assets were modified,
-    // don't re-run the entrypoint detection logic unless the primary input was
-    // actually modified. See issue 16817.
-    return _isEntrypoint(transform.primaryInput).then((isEntrypoint) {
-      if (!isEntrypoint) return null;
-
-      // Wait for any ongoing apply to finish first.
-      return _pool.withResource(() {
-        transform.logger.info("Compiling ${transform.primaryInput.id}...");
-        var stopwatch = new Stopwatch()..start();
-        return _doCompilation(transform).then((_) {
-          stopwatch.stop();
-          transform.logger.info(
-              "Took ${stopwatch.elapsed} to compile " "${transform.primaryInput.id}.");
-        });
-      });
-    });
-  }
-
-  void declareOutputs(DeclaringTransform transform) {
-    var primaryId = transform.primaryId;
-    transform.declareOutput(primaryId.addExtension(".js"));
-    if (_generateSourceMaps) {
-      transform.declareOutput(primaryId.addExtension(".js.map"));
-    }
-  }
-
-  /// Returns whether or not [asset] might be an entrypoint.
-  Future<bool> _isEntrypoint(Asset asset) {
-    return asset.readAsString().then((code) {
-      try {
-        var name = asset.id.path;
-        if (asset.id.package != _environment.rootPackage.name) {
-          name += " in ${asset.id.package}";
-        }
-
-        var parsed = parseCompilationUnit(code, name: name);
-        return dart.isEntrypoint(parsed);
-      } on AnalyzerErrorGroup catch (e) {
-        // If we get a parse error, consider the asset primary so we report
-        // dart2js's more detailed error message instead.
-        return true;
-      }
-    });
-  }
-
-  /// Run the dart2js compiler.
-  Future _doCompilation(Transform transform) {
-    var provider = new _BarbackCompilerProvider(
-        _environment,
-        transform,
-        generateSourceMaps: _generateSourceMaps);
-
-    // Create a "path" to the entrypoint script. The entrypoint may not actually
-    // be on disk, but this gives dart2js a root to resolve relative paths
-    // against.
-    var id = transform.primaryInput.id;
-
-    var entrypoint = _environment.graph.packages[id.package].path(id.path);
-
-    // TODO(rnystrom): Should have more sophisticated error-handling here. Need
-    // to report compile errors to the user in an easily visible way. Need to
-    // make sure paths in errors are mapped to the original source path so they
-    // can understand them.
-    return dart.compile(
-        entrypoint,
-        provider,
-        commandLineOptions: _configCommandLineOptions,
-        csp: _configBool('csp'),
-        checked: _configBool('checked'),
-        minify: _configBool(
-            'minify',
-            defaultsTo: _settings.mode == BarbackMode.RELEASE),
-        verbose: _configBool('verbose'),
-        environment: _configEnvironment,
-        packageRoot: _environment.rootPackage.path("packages"),
-        analyzeAll: _configBool('analyzeAll'),
-        preserveUris: _configBool('preserveUris'),
-        suppressWarnings: _configBool('suppressWarnings'),
-        suppressHints: _configBool('suppressHints'),
-        suppressPackageWarnings: _configBool(
-            'suppressPackageWarnings',
-            defaultsTo: true),
-        terse: _configBool('terse'),
-        includeSourceMapUrls: _generateSourceMaps);
-  }
-
-  /// Parses and returns the "commandLineOptions" configuration option.
-  List<String> get _configCommandLineOptions {
-    if (!_settings.configuration.containsKey('commandLineOptions')) return null;
-
-    var options = _settings.configuration['commandLineOptions'];
-    if (options is List && options.every((option) => option is String)) {
-      return options;
-    }
-
-    throw new FormatException(
-        'Invalid value for '
-            '\$dart2js.commandLineOptions: ${JSON.encode(options)} (expected list '
-            'of strings).');
-  }
-
-  /// Parses and returns the "environment" configuration option.
-  Map<String, String> get _configEnvironment {
-    if (!_settings.configuration.containsKey('environment')) return null;
-
-    var environment = _settings.configuration['environment'];
-    if (environment is Map &&
-        environment.keys.every((key) => key is String) &&
-        environment.values.every((key) => key is String)) {
-      return environment;
-    }
-
-    throw new FormatException(
-        'Invalid value for \$dart2js.environment: '
-            '${JSON.encode(environment)} (expected map from strings to strings).');
-  }
-
-  /// Parses and returns a boolean configuration option.
-  ///
-  /// [defaultsTo] is the default value of the option.
-  bool _configBool(String name, {bool defaultsTo: false}) {
-    if (!_settings.configuration.containsKey(name)) return defaultsTo;
-    var value = _settings.configuration[name];
-    if (value is bool) return value;
-    throw new FormatException(
-        'Invalid value for \$dart2js.$name: '
-            '${JSON.encode(value)} (expected true or false).');
-  }
-}
-
-/// Defines an interface for dart2js to communicate with barback and pub.
-///
-/// Note that most of the implementation of diagnostic handling here was
-/// copied from [FormattingDiagnosticHandler] in dart2js. The primary
-/// difference is that it uses barback's logging code and, more importantly, it
-/// handles missing source files more gracefully.
-class _BarbackCompilerProvider implements dart.CompilerProvider {
-  Uri get libraryRoot => Uri.parse("${path.toUri(_libraryRootPath)}/");
-
-  final AssetEnvironment _environment;
-  final Transform _transform;
-  String _libraryRootPath;
-
-  /// The map of previously loaded files.
-  ///
-  /// Used to show where an error occurred in a source file.
-  final _sourceFiles = new Map<String, SourceFile>();
-
-  // TODO(rnystrom): Make these configurable.
-  /// Whether or not warnings should be logged.
-  var _showWarnings = true;
-
-  /// Whether or not hints should be logged.
-  var _showHints = true;
-
-  /// Whether or not verbose info messages should be logged.
-  var _verbose = false;
-
-  /// Whether an exception should be thrown on an error to stop compilation.
-  var _throwOnError = false;
-
-  /// This gets set after a fatal error is reported to quash any subsequent
-  /// errors.
-  var _isAborting = false;
-
-  final bool generateSourceMaps;
-
-  compiler.Diagnostic _lastKind = null;
-
-  static final int _FATAL =
-      compiler.Diagnostic.CRASH.ordinal |
-      compiler.Diagnostic.ERROR.ordinal;
-  static final int _INFO =
-      compiler.Diagnostic.INFO.ordinal |
-      compiler.Diagnostic.VERBOSE_INFO.ordinal;
-
-  _BarbackCompilerProvider(this._environment, this._transform,
-      {this.generateSourceMaps: true}) {
-    // Dart2js outputs source maps that reference the Dart SDK sources. For
-    // that to work, those sources need to be inside the build environment. We
-    // do that by placing them in a special "$sdk" pseudo-package. In order for
-    // dart2js to generate the right URLs to point to that package, we give it
-    // a library root that corresponds to where that package can be found
-    // relative to the public source directory containing that entrypoint.
-    //
-    // For example, say the package being compiled is "/dev/myapp", the
-    // entrypoint is "web/sub/foo/bar.dart", and the source directory is
-    // "web/sub". This means the SDK sources will be (conceptually) at:
-    //
-    //     /dev/myapp/web/sub/packages/$sdk/lib/
-    //
-    // This implies that the asset path for a file in the SDK is:
-    //
-    //     $sdk|lib/lib/...
-    //
-    // TODO(rnystrom): Fix this if #17751 is fixed.
-    var buildDir =
-        _environment.getSourceDirectoryContaining(_transform.primaryInput.id.path);
-    _libraryRootPath =
-        _environment.rootPackage.path(buildDir, "packages", r"$sdk");
-  }
-
-  /// A [CompilerInputProvider] for dart2js.
-  Future<String> provideInput(Uri resourceUri) {
-    // We only expect to get absolute "file:" URLs from dart2js.
-    assert(resourceUri.isAbsolute);
-    assert(resourceUri.scheme == "file");
-
-    var sourcePath = path.fromUri(resourceUri);
-    return _readResource(resourceUri).then((source) {
-      _sourceFiles[resourceUri.toString()] =
-          new StringSourceFile(resourceUri, path.relative(sourcePath), source);
-      return source;
-    });
-  }
-
-  /// A [CompilerOutputProvider] for dart2js.
-  EventSink<String> provideOutput(String name, String extension) {
-    // TODO(rnystrom): Do this more cleanly. See: #17403.
-    if (!generateSourceMaps && extension.endsWith(".map")) {
-      return new NullSink<String>();
-    }
-
-    // TODO(nweiz): remove this special case when dart2js stops generating these
-    // files.
-    if (extension.endsWith(".precompiled.js")) return new NullSink<String>();
-
-    var primaryId = _transform.primaryInput.id;
-
-    // Dart2js uses an empty string for the name of the entrypoint library.
-    // Otherwise, it's the name of a deferred library.
-    var outPath;
-    if (name == "") {
-      outPath = _transform.primaryInput.id.path;
-    } else {
-      var dirname = path.url.dirname(_transform.primaryInput.id.path);
-      outPath = path.url.join(dirname, name);
-    }
-
-    var id = new AssetId(primaryId.package, "$outPath.$extension");
-
-    // Make a sink that dart2js can write to.
-    var sink = new StreamController<String>();
-
-    // dart2js gives us strings, but stream assets expect byte lists.
-    var stream = UTF8.encoder.bind(sink.stream);
-
-    // And give it to barback as a stream it can read from.
-    _transform.addOutput(new Asset.fromStream(id, stream));
-
-    return sink;
-  }
-
-  /// A [DiagnosticHandler] for dart2js, loosely based on
-  /// [FormattingDiagnosticHandler].
-  void handleDiagnostic(Uri uri, int begin, int end, String message,
-      compiler.Diagnostic kind) {
-    // TODO(ahe): Remove this when source map is handled differently.
-    if (kind.name == "source map") return;
-
-    if (_isAborting) return;
-    _isAborting = (kind == compiler.Diagnostic.CRASH);
-
-    var isInfo = (kind.ordinal & _INFO) != 0;
-    if (isInfo && uri == null && kind != compiler.Diagnostic.INFO) {
-      if (!_verbose && kind == compiler.Diagnostic.VERBOSE_INFO) return;
-      _transform.logger.info(message);
-      return;
-    }
-
-    // [_lastKind] records the previous non-INFO kind we saw.
-    // This is used to suppress info about a warning when warnings are
-    // suppressed, and similar for hints.
-    if (kind != compiler.Diagnostic.INFO) _lastKind = kind;
-
-    var logFn;
-    if (kind == compiler.Diagnostic.ERROR) {
-      logFn = _transform.logger.error;
-    } else if (kind == compiler.Diagnostic.WARNING) {
-      if (!_showWarnings) return;
-      logFn = _transform.logger.warning;
-    } else if (kind == compiler.Diagnostic.HINT) {
-      if (!_showHints) return;
-      logFn = _transform.logger.warning;
-    } else if (kind == compiler.Diagnostic.CRASH) {
-      logFn = _transform.logger.error;
-    } else if (kind == compiler.Diagnostic.INFO) {
-      if (_lastKind == compiler.Diagnostic.WARNING && !_showWarnings) return;
-      if (_lastKind == compiler.Diagnostic.HINT && !_showHints) return;
-      logFn = _transform.logger.info;
-    } else {
-      throw new Exception('Unknown kind: $kind (${kind.ordinal})');
-    }
-
-    var fatal = (kind.ordinal & _FATAL) != 0;
-    if (uri == null) {
-      logFn(message);
-    } else {
-      SourceFile file = _sourceFiles[uri.toString()];
-      if (file == null) {
-        // We got a message before loading the file, so just report the message
-        // itself.
-        logFn('$uri: $message');
-      } else {
-        logFn(file.getLocationMessage(message, begin, end));
-      }
-    }
-
-    if (fatal && _throwOnError) {
-      _isAborting = true;
-      throw new AbortLeg(message);
-    }
-  }
-
-  Future<String> _readResource(Uri url) {
-    return new Future.sync(() {
-      // Find the corresponding asset in barback.
-      var id = _sourceUrlToId(url);
-      if (id != null) return _transform.readInputAsString(id);
-
-      // Don't allow arbitrary file paths that point to things not in packages.
-      // Doing so won't work in Dartium.
-      throw new Exception(
-          "Cannot read $url because it is outside of the build environment.");
-    });
-  }
-
-  AssetId _sourceUrlToId(Uri url) {
-    // See if it's a package path.
-    var id = packagesUrlToId(url);
-    if (id != null) return id;
-
-    // See if it's a path to a "public" asset within the root package. All
-    // other files in the root package are not visible to transformers, so
-    // should be loaded directly from disk.
-    var sourcePath = path.fromUri(url);
-    if (_environment.containsPath(sourcePath)) {
-      var relative =
-          path.toUri(_environment.rootPackage.relative(sourcePath)).toString();
-
-      return new AssetId(_environment.rootPackage.name, relative);
-    }
-
-    return null;
-  }
-}
-
-/// An [EventSink] that discards all data. Provided to dart2js when we don't
-/// want an actual output.
-class NullSink<T> implements EventSink<T> {
-  void add(T event) {}
-  void addError(errorEvent, [StackTrace stackTrace]) {}
-  void close() {}
-}