Revert "Adding package:code_transformers for unifying common transformers code"

pkg/code_transformers/lib/src/resolver_impl.dart

Index: pkg/code_transformers/lib/src/resolver_impl.dart
diff --git a/pkg/code_transformers/lib/src/resolver_impl.dart b/pkg/code_transformers/lib/src/resolver_impl.dart
deleted file mode 100644
index 9ac639954b565923ff676e0052a1d0ebbde0e204..0000000000000000000000000000000000000000
--- a/pkg/code_transformers/lib/src/resolver_impl.dart
+++ /dev/null
@@ -1,545 +0,0 @@
-// Copyright (c) 2014, 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 code_transformer.src.resolver_impl;
-
-import 'dart:async';
-import 'package:analyzer/src/generated/ast.dart';
-import 'package:analyzer/src/generated/element.dart';
-import 'package:analyzer/src/generated/engine.dart';
-import 'package:analyzer/src/generated/error.dart';
-import 'package:analyzer/src/generated/java_io.dart';
-import 'package:analyzer/src/generated/parser.dart' show Parser;
-import 'package:analyzer/src/generated/scanner.dart';
-import 'package:analyzer/src/generated/sdk.dart' show DartSdk;
-import 'package:analyzer/src/generated/sdk_io.dart' show DirectoryBasedDartSdk;
-import 'package:analyzer/src/generated/source.dart';
-import 'package:barback/barback.dart';
-import 'package:path/path.dart' as path;
-import 'package:source_maps/refactor.dart';
-import 'package:source_maps/span.dart' show SourceFile, Span;
-
-import 'resolver.dart';
-
-/// Resolves and updates an AST based on Barback-based assets.
-///
-/// This also provides a handful of useful APIs for traversing and working
-/// with the resolved AST.
-class ResolverImpl implements Resolver {
-  /// Cache of all asset sources currently referenced.
-  final Map<AssetId, _AssetBasedSource> sources =
-      <AssetId, _AssetBasedSource>{};
-
-  /// The Dart entry point file where parsing begins.
-  final AssetId entryPoint;
-
-  final AnalysisContext _context =
-      AnalysisEngine.instance.createAnalysisContext();
-
-  /// Transform for which this is currently updating, or null when not updating.
-  Transform _currentTransform;
-
-  /// The currently resolved library, or null if unresolved.
-  LibraryElement _entryLibrary;
-
-  /// Handler for all Dart SDK (dart:) sources.
-  DirectoryBasedDartSdk _dartSdk;
-
-  /// Creates a resolver that will resolve the Dart code starting at
-  /// [entryPoint].
-  ///
-  /// [sdkDir] is the root directory of the Dart SDK, for resolving dart:
-  /// imports.
-  ResolverImpl(this.entryPoint, String sdkDir, {AnalysisOptions options}) {
-    if (options == null) {
-      options = new AnalysisOptionsImpl()
-        ..cacheSize = 256 // # of sources to cache ASTs for.
-        ..preserveComments = false
-        ..analyzeFunctionBodies = true;
-    }
-    _context.analysisOptions = options;
-
-    _dartSdk = new _DirectoryBasedDartSdkProxy(new JavaFile(sdkDir));
-    _dartSdk.context.analysisOptions = options;
-
-    _context.sourceFactory = new SourceFactory.con2([
-        new DartUriResolverProxy(_dartSdk),
-        new _AssetUriResolver(this)]);
-  }
-
-  LibraryElement get entryLibrary => _entryLibrary;
-
-
-  /// Update the status of all the sources referenced by the entryPoint and
-  /// update the resolved library.
-  ///
-  /// This will be invoked automatically by [ResolverTransformer]. Only one
-  /// transformer may update this at a time.
-  Future updateSources(Transform transform) {
-    if (_currentTransform != null) {
-      throw new StateError('Cannot be accessed by concurrent transforms');
-    }
-    _currentTransform = transform;
-    // Clear this out and update once all asset changes have been processed.
-    _entryLibrary = null;
-
-    // Basic approach is to start at the first file, update it's contents
-    // and see if it changed, then walk all files accessed by it.
-    var visited = new Set<AssetId>();
-    var visiting = new FutureGroup();
-
-    void processAsset(AssetId assetId) {
-      visited.add(assetId);
-
-      visiting.add(transform.readInputAsString(assetId).then((contents) {
-        var source = sources[assetId];
-        if (source == null) {
-          source = new _AssetBasedSource(assetId, this);
-          sources[assetId] = source;
-        }
-        source.updateContents(contents);
-
-        source.dependentAssets
-            .where((id) => !visited.contains(id))
-            .forEach(processAsset);
-
-      }, onError: (e) {
-        _context.applyChanges(new ChangeSet()..removed(sources[assetId]));
-        sources.remove(assetId);
-      }));
-    }
-    processAsset(entryPoint);
-
-    // Once we have all asset sources updated with the new contents then
-    // resolve everything.
-    return visiting.future.then((_) {
-      var changeSet = new ChangeSet();
-      var unreachableAssets = new Set.from(sources.keys).difference(visited);
-      for (var unreachable in unreachableAssets) {
-        changeSet.removed(sources[unreachable]);
-        sources.remove(unreachable);
-      }
-
-      // Update the analyzer context with the latest sources
-      _context.applyChanges(changeSet);
-      // Resolve the AST
-      _entryLibrary = _context.computeLibraryElement(sources[entryPoint]);
-      _currentTransform = null;
-    });
-  }
-
-  Iterable<LibraryElement> get libraries => entryLibrary.visibleLibraries;
-
-  LibraryElement getLibraryByName(String libraryName) =>
-      libraries.firstWhere((l) => l.name == libraryName, orElse: () => null);
-
-  LibraryElement getLibraryByUri(Uri uri) =>
-      libraries.firstWhere((l) => getImportUri(l) == uri, orElse: () => null);
-
-  ClassElement getType(String typeName) {
-    var dotIndex = typeName.lastIndexOf('.');
-    var libraryName = dotIndex == -1 ? '' : typeName.substring(0, dotIndex);
-
-    var className = dotIndex == -1 ?
-        typeName : typeName.substring(dotIndex + 1);
-
-    for (var lib in libraries.where((l) => l.name == libraryName)) {
-      var type = lib.getType(className);
-      if (type != null) return type;
-    }
-    return null;
-  }
-
-  Element getLibraryVariable(String variableName) {
-    var dotIndex = variableName.lastIndexOf('.');
-    var libraryName = dotIndex == -1 ? '' : variableName.substring(0, dotIndex);
-
-    var name = dotIndex == -1 ?
-        variableName : variableName.substring(dotIndex + 1);
-
-    return libraries.where((lib) => lib.name == libraryName)
-        .expand((lib) => lib.units)
-        .expand((unit) => unit.topLevelVariables)
-        .firstWhere((variable) => variable.name == name,
-            orElse: () => null);
-  }
-
-  Element getLibraryFunction(String fnName) {
-    var dotIndex = fnName.lastIndexOf('.');
-    var libraryName = dotIndex == -1 ? '' : fnName.substring(0, dotIndex);
-
-    var name = dotIndex == -1 ?
-        fnName : fnName.substring(dotIndex + 1);
-
-    return libraries.where((lib) => lib.name == libraryName)
-        .expand((lib) => lib.units)
-        .expand((unit) => unit.functions)
-        .firstWhere((fn) => fn.name == name,
-            orElse: () => null);
-  }
-
-  Uri getImportUri(LibraryElement lib, {AssetId from}) =>
-      _getSourceUri(lib, from: from);
-
-
-  /// Similar to getImportUri but will get the part URI for parts rather than
-  /// the library URI.
-  Uri _getSourceUri(Element element, {AssetId from}) {
-    var source = element.source;
-    if (source is _AssetBasedSource) {
-      return source.getSourceUri(from);
-    } else if (source is _DartSourceProxy) {
-      return source.uri;
-    }
-    // Should not be able to encounter any other source types.
-    throw new StateError('Unable to resolve URI for ${source.runtimeType}');
-  }
-
-  AssetId getSourceAssetId(Element element) {
-    var source = element.source;
-    if (source is _AssetBasedSource) return source.assetId;
-    return null;
-  }
-
-  Span getSourceSpan(Element element) {
-    var sourceFile = _getSourceFile(element);
-    if (sourceFile == null) return null;
-    return sourceFile.span(element.node.offset, element.node.end);
-  }
-
-  TextEditTransaction createTextEditTransaction(Element element) {
-    if (element.source is! _AssetBasedSource) return null;
-
-    _AssetBasedSource source = element.source;
-    // Cannot modify assets in other packages.
-    if (source.assetId.package != entryPoint.package) return null;
-
-    var sourceFile = _getSourceFile(element);
-    if (sourceFile == null) return null;
-
-    return new TextEditTransaction(source.contents, sourceFile);
-  }
-
-  /// Gets the SourceFile for the source of the element.
-  SourceFile _getSourceFile(Element element) {
-    var assetId = getSourceAssetId(element);
-    if (assetId == null) return null;
-
-    var importUri = _getSourceUri(element, from: entryPoint);
-    var spanPath = importUri != null ? importUri.toString() : assetId.path;
-    return new SourceFile.text(spanPath, sources[assetId].contents);
-  }
-}
-
-/// Implementation of Analyzer's Source for Barback based assets.
-class _AssetBasedSource extends Source {
-
-  /// Asset ID where this source can be found.
-  final AssetId assetId;
-
-  /// The resolver this is being used in.
-  final ResolverImpl _resolver;
-
-  /// Cache of dependent asset IDs, to avoid re-parsing the AST.
-  Iterable<AssetId> _dependentAssets;
-
-  /// The current revision of the file, incremented only when file changes.
-  int _revision = 0;
-
-  /// The file contents.
-  String _contents;
-
-  _AssetBasedSource(this.assetId, this._resolver);
-
-  /// Update the contents of this file with [contents].
-  ///
-  /// Returns true if the contents of this asset have changed.
-  bool updateContents(String contents) {
-    if (contents == _contents) return false;
-    var added = _contents == null;
-    _contents = contents;
-    ++_revision;
-    // Invalidate the imports so we only parse the AST when needed.
-    _dependentAssets = null;
-
-    if (added) {
-      _resolver._context.applyChanges(new ChangeSet()..added(this));
-    } else {
-      _resolver._context.applyChanges(new ChangeSet()..changed(this));
-    }
-
-    var compilationUnit = _resolver._context.parseCompilationUnit(this);
-    _dependentAssets = compilationUnit.directives
-        .where((d) => (d is ImportDirective || d is PartDirective ||
-            d is ExportDirective))
-        .map((d) => _resolve(assetId, d.uri.stringValue,
-            _logger, _getSpan(d)))
-        .where((id) => id != null).toSet();
-    return true;
-  }
-
-  /// Contents of the file.
-  String get contents => _contents;
-
-  /// Logger for the current transform.
-  ///
-  /// Only valid while the resolver is updating assets.
-  TransformLogger get _logger => _resolver._currentTransform.logger;
-
-  /// Gets all imports/parts/exports which resolve to assets (non-Dart files).
-  Iterable<AssetId> get dependentAssets => _dependentAssets;
-
-  bool exists() => true;
-
-  bool operator ==(Object other) =>
-      other is _AssetBasedSource && assetId == other.assetId;
-
-  int get hashCode => assetId.hashCode;
-
-  void getContents(Source_ContentReceiver receiver) {
-    receiver.accept(contents, modificationStamp);
-  }
-
-  String get encoding =>
-      "${uriKind.encoding}${assetId.package}/${assetId.path}";
-
-  String get fullName => assetId.toString();
-
-  int get modificationStamp => _revision;
-
-  String get shortName => path.basename(assetId.path);
-
-  UriKind get uriKind {
-    if (assetId.path.startsWith('lib/')) return UriKind.PACKAGE_URI;
-    return UriKind.FILE_URI;
-  }
-
-  bool get isInSystemLibrary => false;
-
-  Source resolveRelative(Uri relativeUri) {
-    var id = _resolve(assetId, relativeUri.toString(), _logger, null);
-    if (id == null) return null;
-
-    // The entire AST should have been parsed and loaded at this point.
-    var source = _resolver.sources[id];
-    if (source == null) {
-      _logger.error('Could not load asset $id');
-    }
-    return source;
-  }
-
-  /// For logging errors.
-  Span _getSpan(ASTNode node) => _sourceFile.span(node.offset, node.end);
-  /// For logging errors.
-  SourceFile get _sourceFile {
-    var uri = getSourceUri(_resolver.entryPoint);
-    var path = uri != null ? uri.toString() : assetId.path;
-
-    return new SourceFile.text(path, contents);
-  }
-
-  /// Gets a URI which would be appropriate for importing this file.
-  ///
-  /// Note that this file may represent a non-importable file such as a part.
-  Uri getSourceUri([AssetId from]) {
-    if (!assetId.path.startsWith('lib/')) {
-      // Cannot do absolute imports of non lib-based assets.
-      if (from == null) return null;
-
-      if (assetId.package != from.package) return null;
-      return new Uri(
-          path: path.relative(assetId.path, from: path.dirname(from.path)));
-    }
-
-    return Uri.parse('package:${assetId.package}/${assetId.path.substring(4)}');
-  }
-}
-
-/// Implementation of Analyzer's UriResolver for Barback based assets.
-class _AssetUriResolver implements UriResolver {
-  final ResolverImpl _resolver;
-  _AssetUriResolver(this._resolver);
-
-  Source resolveAbsolute(ContentCache contentCache, Uri uri) {
-    var assetId = _resolve(null, uri.toString(), logger, null);
-    var source = _resolver.sources[assetId];
-    /// All resolved assets should be available by this point.
-    if (source == null) {
-      logger.error('Unable to find asset for "$uri"');
-    }
-    return source;
-  }
-
-  Source fromEncoding(ContentCache contentCache, UriKind kind, Uri uri) =>
-      throw new UnsupportedError('fromEncoding is not supported');
-
-  Uri restoreAbsolute(Source source) =>
-      throw new UnsupportedError('restoreAbsolute is not supported');
-
-  TransformLogger get logger => _resolver._currentTransform.logger;
-}
-
-
-/// Dart SDK which wraps all Dart sources to ensure they are tracked with Uris.
-///
-/// Just a simple wrapper to make it easy to make sure that all sources we
-/// encounter are either _AssetBasedSource or _DartSourceProxy.
-class _DirectoryBasedDartSdkProxy extends DirectoryBasedDartSdk {
-  _DirectoryBasedDartSdkProxy(JavaFile sdkDirectory) : super(sdkDirectory);
-
-  Source mapDartUri(String dartUri) =>
-      _DartSourceProxy.wrap(super.mapDartUri(dartUri), Uri.parse(dartUri));
-}
-
-
-/// Dart SDK resolver which wraps all Dart sources to ensure they are tracked
-/// with URIs.
-class DartUriResolverProxy implements DartUriResolver {
-  final DartUriResolver _proxy;
-  DartUriResolverProxy(DirectoryBasedDartSdk sdk) :
-      _proxy = new DartUriResolver(sdk);
-
-  Source resolveAbsolute(ContentCache contentCache, Uri uri) =>
-    _DartSourceProxy.wrap(_proxy.resolveAbsolute(contentCache, uri), uri);
-
-  DartSdk get dartSdk => _proxy.dartSdk;
-
-  Source fromEncoding(ContentCache contentCache, UriKind kind, Uri uri) =>
-      throw new UnsupportedError('fromEncoding is not supported');
-
-  Uri restoreAbsolute(Source source) =>
-      throw new UnsupportedError('restoreAbsolute is not supported');
-}
-
-/// Source file for dart: sources which track the sources with dart: URIs.
-///
-/// This is primarily to support [Resolver.getImportUri] for Dart SDK (dart:)
-/// based libraries.
-class _DartSourceProxy implements Source {
-
-  /// Absolute URI which this source can be imported from
-  final Uri uri;
-
-  /// Underlying source object.
-  final Source _proxy;
-
-  _DartSourceProxy(this._proxy, this.uri);
-
-  /// Ensures that [source] is a _DartSourceProxy.
-  static _DartSourceProxy wrap(Source source, Uri uri) {
-    if (source == null || source is _DartSourceProxy) return source;
-    return new _DartSourceProxy(source, uri);
-  }
-
-  Source resolveRelative(Uri relativeUri) {
-    // Assume that the type can be accessed via this URI, since these
-    // should only be parts for dart core files.
-    return wrap(_proxy.resolveRelative(relativeUri), uri);
-  }
-
-  bool exists() => _proxy.exists();
-
-  bool operator ==(Object other) =>
-    (other is _DartSourceProxy && _proxy == other._proxy);
-
-  int get hashCode => _proxy.hashCode;
-
-  void getContents(Source_ContentReceiver receiver) {
-    _proxy.getContents(receiver);
-  }
-
-  String get encoding => _proxy.encoding;
-
-  String get fullName => _proxy.fullName;
-
-  int get modificationStamp => _proxy.modificationStamp;
-
-  String get shortName => _proxy.shortName;
-
-  UriKind get uriKind => _proxy.uriKind;
-
-  bool get isInSystemLibrary => _proxy.isInSystemLibrary;
-}
-
-/// Get an asset ID for a URL relative to another source asset.
-AssetId _resolve(AssetId source, String url, TransformLogger logger,
-    Span span) {
-  if (url == null || url == '') return null;
-  var urlBuilder = path.url;
-  var uri = Uri.parse(url);
-
-  if (uri.scheme == 'package') {
-    var segments = new List.from(uri.pathSegments);
-    var package = segments[0];
-    segments[0] = 'lib';
-    return new AssetId(package, segments.join(urlBuilder.separator));
-  }
-  // Dart SDK libraries do not have assets.
-  if (uri.scheme == 'dart') return null;
-
-  if (uri.host != '' || uri.scheme != '' || urlBuilder.isAbsolute(url)) {
-    logger.error('absolute paths not allowed: "$url"', span: span);
-    return null;
-  }
-
-  var targetPath = urlBuilder.normalize(
-      urlBuilder.join(urlBuilder.dirname(source.path), url));
-  return new AssetId(source.package, targetPath);
-}
-
-
-/// A completer that waits until all added [Future]s complete.
-// TODO(blois): Copied from quiver. Remove from here when it gets
-// added to dart:core. (See #6626.)
-class FutureGroup<E> {
-  static const _FINISHED = -1;
-
-  int _pending = 0;
-  Future _failedTask;
-  final Completer<List> _completer = new Completer<List>();
-  final List results = [];
-
-  /** Gets the task that failed, if any. */
-  Future get failedTask => _failedTask;
-
-  /**
-   * Wait for [task] to complete.
-   *
-   * If this group has already been marked as completed, a [StateError] will be
-   * thrown.
-   *
-   * If this group has a [failedTask], new tasks will be ignored, because the
-   * error has already been signaled.
-   */
-  void add(Future task) {
-    if (_failedTask != null) return;
-    if (_pending == _FINISHED) throw new StateError("Future already completed");
-
-    _pending++;
-    var i = results.length;
-    results.add(null);
-    task.then((res) {
-      results[i] = res;
-      if (_failedTask != null) return;
-      _pending--;
-      if (_pending == 0) {
-        _pending = _FINISHED;
-        _completer.complete(results);
-      }
-    }, onError: (e, s) {
-      if (_failedTask != null) return;
-      _failedTask = task;
-      _completer.completeError(e, s);
-    });
-  }
-
-  /**
-   * A Future that complets with a List of the values from all the added
-   * tasks, when they have all completed.
-   *
-   * If any task fails, this Future will receive the error. Only the first
-   * error will be sent to the Future.
-   */
-  Future<List<E>> get future => _completer.future;
-}