Serialize TreeElements

pkg/compiler/lib/src/serialization/task.dart

 // 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.
 
 library dart2js.serialization.task;
 
+import 'dart:async' show Future;
 import '../common/resolution.dart' show ResolutionImpact, ResolutionWorkItem;
 import '../common/tasks.dart' show CompilerTask;
 import '../common/work.dart' show ItemCompilationContext;
 import '../compiler.dart' show Compiler;
 import '../elements/elements.dart';
 import '../enqueue.dart' show ResolutionEnqueuer;
 import '../universe/world_impact.dart' show WorldImpact;
 
 /// A deserializer that can load a library element by reading it's information
 /// from a serialized form.
 abstract class LibraryDeserializer {
   /// Loads the [LibraryElement] associated with a library under [uri], or null
   /// if no serialized information is available for the given library.
-  LibraryElement readLibrary(Uri uri);
+  Future<LibraryElement> readLibrary(Uri uri);
 }
 
 /// Task that supports deserialization of elements.
 class SerializationTask extends CompilerTask implements LibraryDeserializer {
   SerializationTask(Compiler compiler) : super(compiler);
 
   DeserializerSystem deserializer;
 
   String get name => 'Serialization';
 
   /// If `true`, data must be retained to support serialization.
   // TODO(johnniwinther): Make this more precise in terms of what needs to be
   // retained, for instance impacts, resolution data etc.
   bool supportSerialization = false;
 
   /// Returns the [LibraryElement] for [resolvedUri] if available from
   /// serialization.
-  LibraryElement readLibrary(Uri resolvedUri) {
-    if (deserializer == null) return null;
+  Future<LibraryElement> readLibrary(Uri resolvedUri) {
+    if (deserializer == null) return new Future<LibraryElement>.value();
     return deserializer.readLibrary(resolvedUri);
   }
 
   /// Returns `true` if [element] has been deserialized.
   bool isDeserialized(Element element) {
     return deserializer != null && deserializer.isDeserialized(element);
   }
 
   /// Creates the [ResolutionWorkItem] for the deserialized [element].
   ResolutionWorkItem createResolutionWorkItem(
@@ skipping 24 matching lines @@
   WorldImpact run(Compiler compiler, ResolutionEnqueuer world) {
     _isAnalyzed = true;
     world.registerProcessedElement(element);
     return worldImpact;
   }
 }
 
 /// The interface for a system that supports deserialization of libraries and
 /// elements.
 abstract class DeserializerSystem {
-  LibraryElement readLibrary(Uri resolvedUri);
+  Future<LibraryElement> readLibrary(Uri resolvedUri);
   bool isDeserialized(Element element);
+  ResolvedAst getResolvedAst(Element element);
   ResolutionImpact getResolutionImpact(Element element);
   WorldImpact computeWorldImpact(Element element);
 }