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

sdk/lib/_internal/pub_generated/lib/src/pubspec.dart

Index: sdk/lib/_internal/pub_generated/lib/src/pubspec.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/pubspec.dart b/sdk/lib/_internal/pub_generated/lib/src/pubspec.dart
deleted file mode 100644
index 92c068a7b5fa160ad126b99c892614f36cfc76c8..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/lib/src/pubspec.dart
+++ /dev/null
@@ -1,628 +0,0 @@
-// Copyright (c) 2012, 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.pubspec;
-
-import 'package:path/path.dart' as path;
-import 'package:pub_semver/pub_semver.dart';
-import 'package:source_span/source_span.dart';
-import 'package:yaml/yaml.dart';
-
-import 'barback/transformer_config.dart';
-import 'exceptions.dart';
-import 'io.dart';
-import 'package.dart';
-import 'source_registry.dart';
-import 'utils.dart';
-
-/// The parsed contents of a pubspec file.
-///
-/// The fields of a pubspec are, for the most part, validated when they're first
-/// accessed. This allows a partially-invalid pubspec to be used if only the
-/// valid portions are relevant. To get a list of all errors in the pubspec, use
-/// [allErrors].
-class Pubspec {
-  // If a new lazily-initialized field is added to this class and the
-  // initialization can throw a [PubspecException], that error should also be
-  // exposed through [allErrors].
-
-  /// The registry of sources to use when parsing [dependencies] and
-  /// [devDependencies].
-  ///
-  /// This will be null if this was created using [new Pubspec] or [new
-  /// Pubspec.empty].
-  final SourceRegistry _sources;
-
-  /// The location from which the pubspec was loaded.
-  ///
-  /// This can be null if the pubspec was created in-memory or if its location
-  /// is unknown.
-  Uri get _location => fields.span.sourceUrl;
-
-  /// All pubspec fields.
-  ///
-  /// This includes the fields from which other properties are derived.
-  final YamlMap fields;
-
-  /// The package's name.
-  String get name {
-    if (_name != null) return _name;
-
-    var name = fields['name'];
-    if (name == null) {
-      throw new PubspecException(
-          'Missing the required "name" field.',
-          fields.span);
-    } else if (name is! String) {
-      throw new PubspecException(
-          '"name" field must be a string.',
-          fields.nodes['name'].span);
-    }
-
-    _name = name;
-    return _name;
-  }
-  String _name;
-
-  /// The package's version.
-  Version get version {
-    if (_version != null) return _version;
-
-    var version = fields['version'];
-    if (version == null) {
-      _version = Version.none;
-      return _version;
-    }
-
-    var span = fields.nodes['version'].span;
-    if (version is num) {
-      var fixed = '$version.0';
-      if (version is int) {
-        fixed = '$fixed.0';
-      }
-      _error(
-          '"version" field must have three numeric components: major, '
-              'minor, and patch. Instead of "$version", consider "$fixed".',
-          span);
-    }
-    if (version is! String) {
-      _error('"version" field must be a string.', span);
-    }
-
-    _version =
-        _wrapFormatException('version number', span, () => new Version.parse(version));
-    return _version;
-  }
-  Version _version;
-
-  /// The additional packages this package depends on.
-  List<PackageDep> get dependencies {
-    if (_dependencies != null) return _dependencies;
-    _dependencies = _parseDependencies('dependencies');
-    _checkDependencyOverlap(_dependencies, _devDependencies);
-    return _dependencies;
-  }
-  List<PackageDep> _dependencies;
-
-  /// The packages this package depends on when it is the root package.
-  List<PackageDep> get devDependencies {
-    if (_devDependencies != null) return _devDependencies;
-    _devDependencies = _parseDependencies('dev_dependencies');
-    _checkDependencyOverlap(_dependencies, _devDependencies);
-    return _devDependencies;
-  }
-  List<PackageDep> _devDependencies;
-
-  /// The dependency constraints that this package overrides when it is the
-  /// root package.
-  ///
-  /// Dependencies here will replace any dependency on a package with the same
-  /// name anywhere in the dependency graph.
-  List<PackageDep> get dependencyOverrides {
-    if (_dependencyOverrides != null) return _dependencyOverrides;
-    _dependencyOverrides = _parseDependencies('dependency_overrides');
-    return _dependencyOverrides;
-  }
-  List<PackageDep> _dependencyOverrides;
-
-  /// The configurations of the transformers to use for this package.
-  List<Set<TransformerConfig>> get transformers {
-    if (_transformers != null) return _transformers;
-
-    var transformers = fields['transformers'];
-    if (transformers == null) {
-      _transformers = [];
-      return _transformers;
-    }
-
-    if (transformers is! List) {
-      _error(
-          '"transformers" field must be a list.',
-          fields.nodes['transformers'].span);
-    }
-
-    var i = 0;
-    _transformers = transformers.nodes.map((phase) {
-      var phaseNodes = phase is YamlList ? phase.nodes : [phase];
-      return phaseNodes.map((transformerNode) {
-        var transformer = transformerNode.value;
-        if (transformer is! String && transformer is! Map) {
-          _error(
-              'A transformer must be a string or map.',
-              transformerNode.span);
-        }
-
-        var libraryNode;
-        var configurationNode;
-        if (transformer is String) {
-          libraryNode = transformerNode;
-        } else {
-          if (transformer.length != 1) {
-            _error(
-                'A transformer map must have a single key: the transformer ' 'identifier.',
-                transformerNode.span);
-          } else if (transformer.keys.single is! String) {
-            _error(
-                'A transformer identifier must be a string.',
-                transformer.nodes.keys.single.span);
-          }
-
-          libraryNode = transformer.nodes.keys.single;
-          configurationNode = transformer.nodes.values.single;
-          if (configurationNode is! YamlMap) {
-            _error(
-                "A transformer's configuration must be a map.",
-                configurationNode.span);
-          }
-        }
-
-        var config = _wrapSpanFormatException('transformer config', () {
-          return new TransformerConfig.parse(
-              libraryNode.value,
-              libraryNode.span,
-              configurationNode);
-        });
-
-        var package = config.id.package;
-        if (package != name &&
-            !config.id.isBuiltInTransformer &&
-            !dependencies.any((ref) => ref.name == package) &&
-            !devDependencies.any((ref) => ref.name == package) &&
-            !dependencyOverrides.any((ref) => ref.name == package)) {
-          _error('"$package" is not a dependency.', libraryNode.span);
-        }
-
-        return config;
-      }).toSet();
-    }).toList();
-
-    return _transformers;
-  }
-  List<Set<TransformerConfig>> _transformers;
-
-  /// The environment-related metadata.
-  PubspecEnvironment get environment {
-    if (_environment != null) return _environment;
-
-    var yaml = fields['environment'];
-    if (yaml == null) {
-      _environment = new PubspecEnvironment(VersionConstraint.any);
-      return _environment;
-    }
-
-    if (yaml is! Map) {
-      _error(
-          '"environment" field must be a map.',
-          fields.nodes['environment'].span);
-    }
-
-    _environment =
-        new PubspecEnvironment(_parseVersionConstraint(yaml.nodes['sdk']));
-    return _environment;
-  }
-  PubspecEnvironment _environment;
-
-  /// The URL of the server that the package should default to being published
-  /// to, "none" if the package should not be published, or `null` if it should
-  /// be published to the default server.
-  ///
-  /// If this does return a URL string, it will be a valid parseable URL.
-  String get publishTo {
-    if (_parsedPublishTo) return _publishTo;
-
-    var publishTo = fields['publish_to'];
-    if (publishTo != null) {
-      var span = fields.nodes['publish_to'].span;
-
-      if (publishTo is! String) {
-        _error('"publish_to" field must be a string.', span);
-      }
-
-      // It must be "none" or a valid URL.
-      if (publishTo != "none") {
-        _wrapFormatException(
-            '"publish_to" field',
-            span,
-            () => Uri.parse(publishTo));
-      }
-    }
-
-    _parsedPublishTo = true;
-    _publishTo = publishTo;
-    return _publishTo;
-  }
-  bool _parsedPublishTo = false;
-  String _publishTo;
-
-  /// The executables that should be placed on the user's PATH when this
-  /// package is globally activated.
-  ///
-  /// It is a map of strings to string. Each key is the name of the command
-  /// that will be placed on the user's PATH. The value is the name of the
-  /// .dart script (without extension) in the package's `bin` directory that
-  /// should be run for that command. Both key and value must be "simple"
-  /// strings: alphanumerics, underscores and hypens only. If a value is
-  /// omitted, it is inferred to use the same name as the key.
-  Map<String, String> get executables {
-    if (_executables != null) return _executables;
-
-    _executables = {};
-    var yaml = fields['executables'];
-    if (yaml == null) return _executables;
-
-    if (yaml is! Map) {
-      _error(
-          '"executables" field must be a map.',
-          fields.nodes['executables'].span);
-    }
-
-    yaml.nodes.forEach((key, value) {
-      // Don't allow path separators or other stuff meaningful to the shell.
-      validateName(name, description) {
-      }
-
-      if (key.value is! String) {
-        _error('"executables" keys must be strings.', key.span);
-      }
-
-      final keyPattern = new RegExp(r"^[a-zA-Z0-9_-]+$");
-      if (!keyPattern.hasMatch(key.value)) {
-        _error(
-            '"executables" keys may only contain letters, '
-                'numbers, hyphens and underscores.',
-            key.span);
-      }
-
-      if (value.value == null) {
-        value = key;
-      } else if (value.value is! String) {
-        _error('"executables" values must be strings or null.', value.span);
-      }
-
-      final valuePattern = new RegExp(r"[/\\]");
-      if (valuePattern.hasMatch(value.value)) {
-        _error(
-            '"executables" values may not contain path separators.',
-            value.span);
-      }
-
-      _executables[key.value] = value.value;
-    });
-
-    return _executables;
-  }
-  Map<String, String> _executables;
-
-  /// Whether the package is private and cannot be published.
-  ///
-  /// This is specified in the pubspec by setting "publish_to" to "none".
-  bool get isPrivate => publishTo == "none";
-
-  /// Whether or not the pubspec has no contents.
-  bool get isEmpty =>
-      name == null && version == Version.none && dependencies.isEmpty;
-
-  /// Loads the pubspec for a package located in [packageDir].
-  ///
-  /// If [expectedName] is passed and the pubspec doesn't have a matching name
-  /// field, this will throw a [PubspecError].
-  factory Pubspec.load(String packageDir, SourceRegistry sources,
-      {String expectedName}) {
-    var pubspecPath = path.join(packageDir, 'pubspec.yaml');
-    var pubspecUri = path.toUri(pubspecPath);
-    if (!fileExists(pubspecPath)) {
-      throw new FileException(
-          'Could not find a file named "pubspec.yaml" in "$packageDir".',
-          pubspecPath);
-    }
-
-    return new Pubspec.parse(
-        readTextFile(pubspecPath),
-        sources,
-        expectedName: expectedName,
-        location: pubspecUri);
-  }
-
-  Pubspec(this._name, {Version version, Iterable<PackageDep> dependencies,
-      Iterable<PackageDep> devDependencies, Iterable<PackageDep> dependencyOverrides,
-      VersionConstraint sdkConstraint,
-      Iterable<Iterable<TransformerConfig>> transformers, Map fields,
-      SourceRegistry sources})
-      : _version = version,
-        _dependencies = dependencies == null ? null : dependencies.toList(),
-        _devDependencies = devDependencies == null ?
-          null :
-          devDependencies.toList(),
-        _dependencyOverrides = dependencyOverrides == null ?
-          null :
-          dependencyOverrides.toList(),
-        _environment = new PubspecEnvironment(sdkConstraint),
-        _transformers = transformers == null ?
-          [] :
-          transformers.map((phase) => phase.toSet()).toList(),
-        fields = fields == null ? new YamlMap() : new YamlMap.wrap(fields),
-        _sources = sources;
-
-  Pubspec.empty()
-      : _sources = null,
-        _name = null,
-        _version = Version.none,
-        _dependencies = <PackageDep>[],
-        _devDependencies = <PackageDep>[],
-        _environment = new PubspecEnvironment(),
-        _transformers = <Set<TransformerConfig>>[],
-        fields = new YamlMap();
-
-  /// Returns a Pubspec object for an already-parsed map representing its
-  /// contents.
-  ///
-  /// If [expectedName] is passed and the pubspec doesn't have a matching name
-  /// field, this will throw a [PubspecError].
-  ///
-  /// [location] is the location from which this pubspec was loaded.
-  Pubspec.fromMap(Map fields, this._sources, {String expectedName,
-      Uri location})
-      : fields = fields is YamlMap ?
-          fields :
-          new YamlMap.wrap(fields, sourceUrl: location) {
-    // If [expectedName] is passed, ensure that the actual 'name' field exists
-    // and matches the expectation.
-    if (expectedName == null) return;
-    if (name == expectedName) return;
-
-    throw new PubspecException(
-        '"name" field doesn\'t match expected name ' '"$expectedName".',
-        this.fields.nodes["name"].span);
-  }
-
-  /// Parses the pubspec stored at [filePath] whose text is [contents].
-  ///
-  /// If the pubspec doesn't define a version for itself, it defaults to
-  /// [Version.none].
-  factory Pubspec.parse(String contents, SourceRegistry sources,
-      {String expectedName, Uri location}) {
-    var pubspecNode = loadYamlNode(contents, sourceUrl: location);
-    if (pubspecNode is YamlScalar && pubspecNode.value == null) {
-      pubspecNode = new YamlMap(sourceUrl: location);
-    } else if (pubspecNode is! YamlMap) {
-      throw new PubspecException(
-          'The pubspec must be a YAML mapping.',
-          pubspecNode.span);
-    }
-
-    return new Pubspec.fromMap(
-        pubspecNode,
-        sources,
-        expectedName: expectedName,
-        location: location);
-  }
-
-  /// Returns a list of most errors in this pubspec.
-  ///
-  /// This will return at most one error for each field.
-  List<PubspecException> get allErrors {
-    var errors = <PubspecException>[];
-    _getError(fn()) {
-      try {
-        fn();
-      } on PubspecException catch (e) {
-        errors.add(e);
-      }
-    }
-
-    _getError(() => this.name);
-    _getError(() => this.version);
-    _getError(() => this.dependencies);
-    _getError(() => this.devDependencies);
-    _getError(() => this.transformers);
-    _getError(() => this.environment);
-    _getError(() => this.publishTo);
-    return errors;
-  }
-
-  /// Parses the dependency field named [field], and returns the corresponding
-  /// list of dependencies.
-  List<PackageDep> _parseDependencies(String field) {
-    var dependencies = <PackageDep>[];
-
-    var yaml = fields[field];
-    // Allow an empty dependencies key.
-    if (yaml == null) return dependencies;
-
-    if (yaml is! Map) {
-      _error('"$field" field must be a map.', fields.nodes[field].span);
-    }
-
-    var nonStringNode =
-        yaml.nodes.keys.firstWhere((e) => e.value is! String, orElse: () => null);
-    if (nonStringNode != null) {
-      _error('A dependency name must be a string.', nonStringNode.span);
-    }
-
-    yaml.nodes.forEach((nameNode, specNode) {
-      var name = nameNode.value;
-      var spec = specNode.value;
-      if (fields['name'] != null && name == this.name) {
-        _error('A package may not list itself as a dependency.', nameNode.span);
-      }
-
-      var descriptionNode;
-      var sourceName;
-
-      var versionConstraint = new VersionRange();
-      if (spec == null) {
-        descriptionNode = nameNode;
-        sourceName = _sources.defaultSource.name;
-      } else if (spec is String) {
-        descriptionNode = nameNode;
-        sourceName = _sources.defaultSource.name;
-        versionConstraint = _parseVersionConstraint(specNode);
-      } else if (spec is Map) {
-        // Don't write to the immutable YAML map.
-        spec = new Map.from(spec);
-
-        if (spec.containsKey('version')) {
-          spec.remove('version');
-          versionConstraint =
-              _parseVersionConstraint(specNode.nodes['version']);
-        }
-
-        var sourceNames = spec.keys.toList();
-        if (sourceNames.length > 1) {
-          _error('A dependency may only have one source.', specNode.span);
-        }
-
-        sourceName = sourceNames.single;
-        if (sourceName is! String) {
-          _error(
-              'A source name must be a string.',
-              specNode.nodes.keys.single.span);
-        }
-
-        descriptionNode = specNode.nodes[sourceName];
-      } else {
-        _error(
-            'A dependency specification must be a string or a mapping.',
-            specNode.span);
-      }
-
-      // Let the source validate the description.
-      var description =
-          _wrapFormatException('description', descriptionNode.span, () {
-        var pubspecPath;
-        if (_location != null && _isFileUri(_location)) {
-          pubspecPath = path.fromUri(_location);
-        }
-
-        return _sources[sourceName].parseDescription(
-            pubspecPath,
-            descriptionNode.value,
-            fromLockFile: false);
-      });
-
-      dependencies.add(
-          new PackageDep(name, sourceName, versionConstraint, description));
-    });
-
-    return dependencies;
-  }
-
-  /// Parses [node] to a [VersionConstraint].
-  VersionConstraint _parseVersionConstraint(YamlNode node) {
-    if (node.value == null) return VersionConstraint.any;
-    if (node.value is! String) {
-      _error('A version constraint must be a string.', node.span);
-    }
-
-    return _wrapFormatException(
-        'version constraint',
-        node.span,
-        () => new VersionConstraint.parse(node.value));
-  }
-
-  /// Makes sure the same package doesn't appear as both a regular and dev
-  /// dependency.
-  void _checkDependencyOverlap(List<PackageDep> dependencies,
-      List<PackageDep> devDependencies) {
-    if (dependencies == null) return;
-    if (devDependencies == null) return;
-
-    var dependencyNames = dependencies.map((dep) => dep.name).toSet();
-    var collisions =
-        dependencyNames.intersection(devDependencies.map((dep) => dep.name).toSet());
-    if (collisions.isEmpty) return;
-
-    var span = fields["dependencies"].nodes.keys.firstWhere(
-        (key) => collisions.contains(key.value)).span;
-
-    // TODO(nweiz): associate source range info with PackageDeps and use it
-    // here.
-    _error(
-        '${pluralize('Package', collisions.length)} '
-            '${toSentence(collisions.map((package) => '"$package"'))} cannot '
-            'appear in both "dependencies" and "dev_dependencies".',
-        span);
-  }
-
-  /// Runs [fn] and wraps any [FormatException] it throws in a
-  /// [PubspecException].
-  ///
-  /// [description] should be a noun phrase that describes whatever's being
-  /// parsed or processed by [fn]. [span] should be the location of whatever's
-  /// being processed within the pubspec.
-  _wrapFormatException(String description, SourceSpan span, fn()) {
-    try {
-      return fn();
-    } on FormatException catch (e) {
-      _error('Invalid $description: ${e.message}', span);
-    }
-  }
-
-  _wrapSpanFormatException(String description, fn()) {
-    try {
-      return fn();
-    } on SourceSpanFormatException catch (e) {
-      _error('Invalid $description: ${e.message}', e.span);
-    }
-  }
-
-  /// Throws a [PubspecException] with the given message.
-  void _error(String message, SourceSpan span) {
-    var name;
-    try {
-      name = this.name;
-    } on PubspecException catch (_) {
-      // [name] is null.
-    }
-
-    throw new PubspecException(message, span);
-  }
-}
-
-/// The environment-related metadata in the pubspec.
-///
-/// Corresponds to the data under the "environment:" key in the pubspec.
-class PubspecEnvironment {
-  /// The version constraint specifying which SDK versions this package works
-  /// with.
-  final VersionConstraint sdkVersion;
-
-  PubspecEnvironment([VersionConstraint sdk])
-      : sdkVersion = sdk != null ? sdk : VersionConstraint.any;
-}
-
-/// An exception thrown when parsing a pubspec.
-///
-/// These exceptions are often thrown lazily while accessing pubspec properties.
-class PubspecException extends SourceSpanFormatException implements
-    ApplicationException {
-  PubspecException(String message, SourceSpan span)
-      : super(message, span);
-}
-
-/// Returns whether [uri] is a file URI.
-///
-/// This is slightly more complicated than just checking if the scheme is
-/// 'file', since relative URIs also refer to the filesystem on the VM.
-bool _isFileUri(Uri uri) => uri.scheme == 'file' || uri.scheme == '';