fixes #219, able to compile multiple entry points

lib/src/dependency_graph.dart

Index: lib/src/dependency_graph.dart
diff --git a/lib/src/dependency_graph.dart b/lib/src/dependency_graph.dart
deleted file mode 100644
index c2f75d6fdf2139b81e697317f798fc5db04713f1..0000000000000000000000000000000000000000
--- a/lib/src/dependency_graph.dart
+++ /dev/null
@@ -1,552 +0,0 @@
-// Copyright (c) 2015, 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.
-
-/// Tracks the shape of the import/export graph and dependencies between files.
-library dev_compiler.src.dependency_graph;
-
-import 'dart:collection' show HashSet, HashMap;
-
-import 'package:analyzer/analyzer.dart' show parseDirectives;
-import 'package:analyzer/src/generated/ast.dart'
-    show
-        AstNode,
-        CompilationUnit,
-        ExportDirective,
-        Identifier,
-        ImportDirective,
-        LibraryDirective,
-        PartDirective,
-        PartOfDirective,
-        UriBasedDirective;
-import 'package:analyzer/src/generated/engine.dart'
-    show ParseDartTask, AnalysisContext;
-import 'package:analyzer/src/generated/error.dart';
-import 'package:analyzer/src/generated/source.dart' show Source, SourceKind;
-import 'package:html/dom.dart' show Document, Node, Element;
-import 'package:html/parser.dart' as html;
-import 'package:logging/logging.dart' show Logger, Level;
-import 'package:path/path.dart' as path;
-
-import 'info.dart';
-import 'options.dart';
-import 'report.dart';
-
-/// Holds references to all source nodes in the import graph. This is mainly
-/// used as a level of indirection to ensure that each source has a canonical
-/// representation.
-class SourceGraph {
-  /// All nodes in the source graph. Used to get a canonical representation for
-  /// any node.
-  final Map<Uri, SourceNode> nodes = {};
-
-  /// Resources included by default on any application.
-  final runtimeDeps = new Set<ResourceSourceNode>();
-
-  /// Analyzer used to resolve source files.
-  final AnalysisContext _context;
-  final AnalysisErrorListener _reporter;
-  final CompilerOptions _options;
-
-  SourceGraph(this._context, this._reporter, this._options) {
-    var dir = _options.runtimeDir;
-    if (dir == null) {
-      _log.severe('Runtime dir could not be determined automatically, '
-          'please specify the --runtime-dir flag on the command line.');
-      return;
-    }
-    var prefix = path.absolute(dir);
-    var files = _options.serverMode
-        ? runtimeFilesForServerMode(_options.widget)
-        : defaultRuntimeFiles;
-    for (var file in files) {
-      runtimeDeps.add(nodeFromUri(path.toUri(path.join(prefix, file))));
-    }
-  }
-
-  /// Node associated with a resolved [uri].
-  SourceNode nodeFromUri(Uri uri) {
-    var uriString = Uri.encodeFull('$uri');
-    return nodes.putIfAbsent(uri, () {
-      var source = _context.sourceFactory.forUri(uriString);
-      var extension = path.extension(uriString);
-      if (extension == '.html') {
-        return new HtmlSourceNode(this, uri, source);
-      } else if (extension == '.dart' || uriString.startsWith('dart:')) {
-        return new DartSourceNode(this, uri, source);
-      } else {
-        return new ResourceSourceNode(this, uri, source);
-      }
-    });
-  }
-
-  List<String> get resources => _options.sourceOptions.resources;
-}
-
-/// A node in the import graph representing a source file.
-abstract class SourceNode {
-  final SourceGraph graph;
-
-  /// Resolved URI for this node.
-  final Uri uri;
-
-  /// Resolved source from the analyzer. We let the analyzer internally track
-  /// for modifications to the source files.
-  Source _source;
-  Source get source => _source;
-
-  String get contents => graph._context.getContents(_source).data;
-
-  /// Last stamp read from `source.modificationStamp`.
-  /// This starts at -1, because analyzer uses that for files that don't exist.
-  int _lastStamp = -1;
-
-  /// A hash used to help browsers cache the output that would be produced from
-  /// building this node.
-  String cachingHash;
-
-  /// Whether we need to rebuild this source file.
-  bool needsRebuild = false;
-
-  /// Whether the structure of dependencies from this node (scripts, imports,
-  /// exports, or parts) changed after we reparsed its contents.
-  bool structureChanged = false;
-
-  /// Direct dependencies in the [SourceGraph]. These include script tags for
-  /// [HtmlSourceNode]s; and imports, exports and parts for [DartSourceNode]s.
-  Iterable<SourceNode> get allDeps => const [];
-
-  /// Like [allDeps] but excludes parts for [DartSourceNode]s. For many
-  /// operations we mainly care about dependencies at the library level, so
-  /// parts are excluded from this list.
-  Iterable<SourceNode> get depsWithoutParts => const [];
-
-  SourceNode(this.graph, this.uri, this._source);
-
-  /// Check for whether the file has changed and, if so, mark [needsRebuild] and
-  /// [structureChanged] as necessary.
-  void update() {
-    if (_source == null) {
-      _source = graph._context.sourceFactory.forUri(Uri.encodeFull('$uri'));
-      if (_source == null) return;
-    }
-
-    int newStamp = _source.exists() ? _source.modificationStamp : -1;
-    if (newStamp > _lastStamp || newStamp == -1 && _lastStamp != -1) {
-      // If the timestamp changed, read the file from disk and cache it.
-      // We don't want the source text to change during compilation.
-      saveUpdatedContents();
-      _lastStamp = newStamp;
-      needsRebuild = true;
-    }
-  }
-
-  void saveUpdatedContents() {}
-
-  String toString() {
-    var simpleUri = uri.scheme == 'file' ? path.relative(uri.path) : "$uri";
-    return '[$runtimeType: $simpleUri]';
-  }
-}
-
-/// A node representing an entry HTML source file.
-class HtmlSourceNode extends SourceNode {
-  /// Resources included by default on any application.
-  final runtimeDeps;
-
-  /// Libraries referred to via script tags.
-  Set<DartSourceNode> scripts = new Set<DartSourceNode>();
-
-  /// Link-rel stylesheets, images, and other specified files.
-  Set<SourceNode> resources = new Set<SourceNode>();
-
-  @override
-  Iterable<SourceNode> get allDeps =>
-      [scripts, resources, runtimeDeps].expand((e) => e);
-
-  @override
-  Iterable<SourceNode> get depsWithoutParts => allDeps;
-
-  /// Parsed document, updated whenever [update] is invoked.
-  Document document;
-
-  /// Tracks resource files referenced from HTML nodes, e.g.
-  /// `<link rel=stylesheet href=...>` and `<img src=...>`
-  final htmlResourceNodes = new HashMap<Element, ResourceSourceNode>();
-
-  HtmlSourceNode(SourceGraph graph, Uri uri, Source source)
-      : runtimeDeps = graph.runtimeDeps,
-        super(graph, uri, source);
-
-  @override
-  void update() {
-    super.update();
-    if (needsRebuild) {
-      var reporter = graph._reporter;
-      if (reporter is SummaryReporter) {
-        reporter.clearHtml(uri);
-      }
-      document = html.parse(contents, generateSpans: true);
-      var newScripts = new Set<DartSourceNode>();
-      var tags = document.querySelectorAll('script[type="application/dart"]');
-      for (var script in tags) {
-        var src = script.attributes['src'];
-        if (src == null) {
-          _reportError(graph, 'inlined script tags not supported at this time '
-              '(see https://github.com/dart-lang/dart-dev-compiler/issues/54).',
-              script);
-          continue;
-        }
-        var node = graph.nodeFromUri(uri.resolve(src));
-        if (node == null || !node.source.exists()) {
-          _reportError(graph, 'Script file $src not found', script);
-        }
-        if (node != null) newScripts.add(node);
-      }
-
-      if (!_same(newScripts, scripts)) {
-        structureChanged = true;
-        scripts = newScripts;
-      }
-
-      // TODO(jmesserly): simplify the design here. Ideally we wouldn't need
-      // to track user-defined CSS, images, etc. Also we don't have a clear
-      // way to distinguish runtime injected resources, like messages.css, from
-      // user-defined files.
-      htmlResourceNodes.clear();
-      var newResources = new Set<SourceNode>();
-      for (var resource in graph.resources) {
-        newResources.add(graph.nodeFromUri(uri.resolve(resource)));
-      }
-      for (var tag in document.querySelectorAll('link[rel="stylesheet"]')) {
-        var res = graph.nodeFromUri(uri.resolve(tag.attributes['href']));
-        htmlResourceNodes[tag] = res;
-        newResources.add(res);
-      }
-      for (var tag in document.querySelectorAll('img[src]')) {
-        var res = graph.nodeFromUri(uri.resolve(tag.attributes['src']));
-        htmlResourceNodes[tag] = res;
-        newResources.add(res);
-      }
-      if (!_same(newResources, resources)) {
-        structureChanged = true;
-        resources = newResources;
-      }
-    }
-  }
-
-  void _reportError(SourceGraph graph, String message, Node node) {
-    var span = node.sourceSpan;
-
-    // TODO(jmesserly): should these be errors or warnings?
-    var errorCode = new HtmlWarningCode('dev_compiler.$runtimeType', message);
-    graph._reporter.onError(
-        new AnalysisError(_source, span.start.offset, span.length, errorCode));
-  }
-}
-
-/// A node representing a Dart library or part.
-class DartSourceNode extends SourceNode {
-  /// Set of imported libraries (empty for part files).
-  Set<DartSourceNode> imports = new Set<DartSourceNode>();
-
-  /// Set of exported libraries (empty for part files).
-  Set<DartSourceNode> exports = new Set<DartSourceNode>();
-
-  /// Parts of this library (empty for part files).
-  Set<DartSourceNode> parts = new Set<DartSourceNode>();
-
-  /// How many times this file is included as a part.
-  int includedAsPart = 0;
-
-  DartSourceNode(graph, uri, source) : super(graph, uri, source);
-
-  @override
-  Iterable<SourceNode> get allDeps =>
-      [imports, exports, parts].expand((e) => e);
-
-  @override
-  Iterable<SourceNode> get depsWithoutParts =>
-      [imports, exports].expand((e) => e);
-
-  LibraryInfo info;
-
-  // TODO(jmesserly): it would be nice to not keep all sources in memory at
-  // once, but how else can we ensure a consistent view across a given
-  // compile? One different from dev_compiler vs analyzer is that our
-  // messages later in the compiler need the original source text to print
-  // spans. We also read source text ourselves to parse directives.
-  // But we could discard it after that point.
-  void saveUpdatedContents() {
-    graph._context.setContents(_source, _source.contents.data);
-  }
-
-  @override
-  void update() {
-    super.update();
-
-    if (needsRebuild) {
-      var reporter = graph._reporter;
-      if (reporter is SummaryReporter) {
-        reporter.clearLibrary(uri);
-      }
-
-      // If the defining compilation-unit changed, the structure might have
-      // changed.
-      var unit = parseDirectives(contents, name: _source.fullName);
-      var newImports = new Set<DartSourceNode>();
-      var newExports = new Set<DartSourceNode>();
-      var newParts = new Set<DartSourceNode>();
-      for (var d in unit.directives) {
-        // Nothing to do for parts.
-        if (d is PartOfDirective) return;
-        if (d is LibraryDirective) continue;
-
-        var directiveUri = (d as UriBasedDirective).uri;
-
-        // `dart:core` and other similar URLs only contain a name, but it is
-        // meant to be a folder when resolving relative paths from it.
-        var targetUri = uri.scheme == 'dart' && uri.pathSegments.length == 1
-            ? Uri.parse('$uri/').resolve(directiveUri.stringValue)
-            : uri.resolve(directiveUri.stringValue);
-        var target =
-            ParseDartTask.resolveDirective(graph._context, _source, d, null);
-        var node = graph.nodes.putIfAbsent(
-            targetUri, () => new DartSourceNode(graph, targetUri, target));
-        //var node = graph.nodeFromUri(targetUri);
-        if (node._source == null || !node._source.exists()) {
-          _reportError(graph, 'File $targetUri not found', d);
-        }
-
-        if (d is ImportDirective) {
-          newImports.add(node);
-        } else if (d is ExportDirective) {
-          newExports.add(node);
-        } else if (d is PartDirective) {
-          newParts.add(node);
-        }
-      }
-
-      if (!_same(newImports, imports)) {
-        structureChanged = true;
-        imports = newImports;
-      }
-
-      if (!_same(newExports, exports)) {
-        structureChanged = true;
-        exports = newExports;
-      }
-
-      if (!_same(newParts, parts)) {
-        structureChanged = true;
-
-        // When parts are removed, it's possible they were updated to be
-        // imported as a library
-        for (var p in parts) {
-          if (newParts.contains(p)) continue;
-          if (--p.includedAsPart == 0) {
-            p.needsRebuild = true;
-          }
-        }
-
-        for (var p in newParts) {
-          if (parts.contains(p)) continue;
-          p.includedAsPart++;
-        }
-        parts = newParts;
-      }
-    }
-
-    // The library should be marked as needing rebuild if a part changed
-    // internally:
-    for (var p in parts) {
-      // Technically for parts we don't need to look at the contents. If they
-      // contain imports, exports, or parts, we'll ignore them in our crawling.
-      // However we do a full update to make it easier to adjust when users
-      // switch a file from a part to a library.
-      p.update();
-      if (p.needsRebuild) needsRebuild = true;
-    }
-  }
-
-  void _reportError(SourceGraph graph, String message, AstNode node) {
-    graph._reporter.onError(new AnalysisError(_source, node.offset, node.length,
-        new CompileTimeErrorCode('dev_compiler.$runtimeType', message)));
-  }
-}
-
-/// Represents a runtime resource from our compiler that is needed to run an
-/// application.
-class ResourceSourceNode extends SourceNode {
-  ResourceSourceNode(graph, uri, source) : super(graph, uri, source);
-}
-
-/// Updates the structure and `needsRebuild` marks in nodes of [graph] reachable
-/// from [start].
-///
-/// That is, staring from [start], we update the graph by detecting file changes
-/// and rebuilding the structure of the graph wherever it changed (an import was
-/// added or removed, etc).
-///
-/// After calling this function a node is marked with `needsRebuild` only if it
-/// contained local changes. Rebuild decisions that derive from transitive
-/// changes (e.g. when the API of a dependency changed) are handled later in
-/// [rebuild].
-void refreshStructureAndMarks(SourceNode start) {
-  visitInPreOrder(start, (n) => n.update(), includeParts: false);
-}
-
-/// Clears all the `needsRebuild` and `structureChanged` marks in nodes
-/// reachable from [start].
-void clearMarks(SourceNode start) {
-  visitInPreOrder(start, (n) => n.needsRebuild = n.structureChanged = false,
-      includeParts: true);
-}
-
-/// Traverses from [start] with the purpose of building any source that needs to
-/// be rebuilt.
-///
-/// This function will call [build] in a post-order fashion, on a subset of the
-/// reachable nodes. There are four rules used to decide when to rebuild a node
-/// (call [build] on a node):
-///
-///   * Only rebuild Dart libraries ([DartSourceNode]) or HTML files
-///     ([HtmlSourceNode]), but skip part files. That is because those are
-///     built as part of some library.
-///
-///   * Always rebuild [DartSourceNode]s and [HtmlSourceNode]s with local
-///     changes or changes in a part of the library. Internally this function
-///     calls [refreshStructureAndMarks] to ensure that the graph structure is
-///     up-to-date and that these nodes with local changes contain the
-///     `needsRebuild` bit.
-///
-///   * Rebuild [HtmlSourceNode]s if there were structural changes somewhere
-///     down its reachable subgraph. This is done because HTML files embed the
-///     transitive closure of the import graph in their output.
-///
-///   * Rebuild [DartSourceNode]s that depend on other [DartSourceNode]s
-///     whose API may have changed. The result of [build] is used to determine
-///     whether other nodes need to be rebuilt. The function [build] is expected
-///     to return `true` on a node `n` if it detemines other nodes that import
-///     `n` may need to be rebuilt as well.
-rebuild(SourceNode start, bool build(SourceNode node)) {
-  refreshStructureAndMarks(start);
-  // Hold which source nodes may have changed their public API, this includes
-  // libraries that were modified or libraries that export other modified APIs.
-  // TODO(sigmund): consider removing this special support for exports? Many
-  // cases anways require using summaries to understand what parts of the public
-  // API may be affected by transitive changes. The re-export case is just one
-  // of those transitive cases, but is not sufficient. See
-  // https://github.com/dart-lang/dev_compiler/issues/76
-  var apiChangeDetected = new HashSet<SourceNode>();
-  bool htmlNeedsRebuild = false;
-
-  bool shouldBuildNode(SourceNode n) {
-    if (n.needsRebuild) return true;
-    if (n is HtmlSourceNode) return htmlNeedsRebuild;
-    if (n is ResourceSourceNode) return false;
-    return (n as DartSourceNode).imports
-        .any((i) => apiChangeDetected.contains(i));
-  }
-
-  visitInPostOrder(start, (n) {
-    if (n.structureChanged) htmlNeedsRebuild = true;
-    if (shouldBuildNode(n)) {
-      var oldHash = n.cachingHash;
-      if (build(n)) apiChangeDetected.add(n);
-      if (oldHash != n.cachingHash) htmlNeedsRebuild = true;
-    } else if (n is DartSourceNode &&
-        n.exports.any((e) => apiChangeDetected.contains(e))) {
-      apiChangeDetected.add(n);
-    }
-    n.needsRebuild = false;
-    n.structureChanged = false;
-    if (n is DartSourceNode) {
-      // Note: clearing out flags in the parts could be a problem if someone
-      // tries to use a file both as a part and a library at the same time.
-      // In that case, we might not correctly propagate changes in the places
-      // where it is used as a library. Technically it's not allowed to have a
-      // file as a part and a library at once, and the analyzer should report an
-      // error in that case.
-      n.parts.forEach((p) => p.needsRebuild = p.structureChanged = false);
-    }
-  }, includeParts: false);
-}
-
-/// Helper that runs [action] on nodes reachable from [start] in pre-order.
-visitInPreOrder(SourceNode start, void action(SourceNode node),
-    {bool includeParts: false}) {
-  var seen = new HashSet<SourceNode>();
-  helper(SourceNode node) {
-    if (!seen.add(node)) return;
-    action(node);
-    var deps = includeParts ? node.allDeps : node.depsWithoutParts;
-    deps.forEach(helper);
-  }
-  helper(start);
-}
-
-/// Helper that runs [action] on nodes reachable from [start] in post-order.
-visitInPostOrder(SourceNode start, void action(SourceNode node),
-    {bool includeParts: false}) {
-  var seen = new HashSet<SourceNode>();
-  helper(SourceNode node) {
-    if (!seen.add(node)) return;
-    var deps = includeParts ? node.allDeps : node.depsWithoutParts;
-    deps.forEach(helper);
-    action(node);
-  }
-  helper(start);
-}
-
-bool _same(Set a, Set b) => a.length == b.length && a.containsAll(b);
-
-/// Runtime files added to all applications when running the compiler in the
-/// command line.
-final defaultRuntimeFiles = () {
-  var files = [
-    'harmony_feature_check.js',
-    'dart_utils.js',
-    'dart_library.js',
-    '_errors.js',
-    '_types.js',
-    '_rtti.js',
-    '_classes.js',
-    '_operations.js',
-    'dart_runtime.js',
-  ];
-  files.addAll(corelibOrder.map((l) => l.replaceAll('.', '/') + '.js'));
-  return files;
-}();
-
-/// Curated order to minimize lazy classes needed by dart:core and its
-/// transitive SDK imports.
-const corelibOrder = const [
-  'dart.core',
-  'dart.collection',
-  'dart._internal',
-  'dart.math',
-  'dart._interceptors',
-  'dart.async',
-  'dart._foreign_helper',
-  'dart._js_embedded_names',
-  'dart._js_helper',
-  'dart.isolate',
-  'dart.typed_data',
-  'dart._native_typed_data',
-  'dart._isolate_helper',
-  'dart._js_primitives',
-  'dart.convert',
-  'dart.mirrors',
-  'dart._js_mirrors',
-  'dart.js'
-  // _foreign_helper is not included, as it only defines the JS builtin that
-  // the compiler handles at compile time.
-];
-
-/// Runtime files added to applications when running in server mode.
-List<String> runtimeFilesForServerMode([bool includeWidget = true]) =>
-    new List<String>.from(defaultRuntimeFiles)
-  ..addAll(includeWidget ? const ['messages_widget.js', 'messages.css'] : []);
-
-final _log = new Logger('dev_compiler.dependency_graph');