Expand barback's notion of dirtiness to understand declaredness.

pkg/barback/lib/src/group_runner.dart

 // 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 barback.group_runner;
 
 import 'dart:async';
 
 import 'asset_cascade.dart';
 import 'asset_node.dart';
 import 'log.dart';
+import 'node_status.dart';
 import 'phase.dart';
 import 'stream_pool.dart';
 import 'transformer_group.dart';
 
 /// A class that processes all of the phases in a single transformer group.
 ///
 /// A group takes many inputs, processes them, and emits many outputs.
 class GroupRunner {
   /// The group this runner runs.
   final TransformerGroup _group;
 
   /// A string describing the location of [this] in the transformer graph.
   final String _location;
 
   /// The phases defined by this group.
   final _phases = new List<Phase>();
 
-  /// Whether [this] is dirty and still has more processing to do.
-  bool get isDirty {
+  /// How far along [this] is in processing its assets.
+  NodeStatus get status {
     // Just check the last phase, since it will check all the previous phases
     // itself.
-    return _phases.last.isDirty;
+    return _phases.last.status;
   }
 
-  /// A stream that emits an event whenever [this] is no longer dirty.
-  ///
-  /// This is synchronous in order to guarantee that it will emit an event as
-  /// soon as [isDirty] flips from `true` to `false`.
-  Stream get onDone => _onDone;
-  Stream _onDone;
+  /// A stream that emits an event every time the group's status changes.
+  Stream<NodeStatus> get onStatusChange => _onStatusChange;
+  Stream _onStatusChange;
 
   /// A stream that emits any new assets emitted by [this].
   ///
   /// Assets are emitted synchronously to ensure that any changes are thoroughly
   /// propagated as soon as they occur.
   Stream<AssetNode> get onAsset => _onAsset;
   Stream<AssetNode> _onAsset;
 
   /// A stream that emits an event whenever any transforms in this group logs
   /// an entry.
   Stream<LogEntry> get onLog => _onLogPool.stream;
   final _onLogPool = new StreamPool<LogEntry>.broadcast();
 
   GroupRunner(AssetCascade cascade, this._group, this._location) {
     _addPhase(new Phase(cascade, _location), []);
     for (var phase in _group.phases) {
       _addPhase(_phases.last.addPhase(), phase);
     }
 
     _onAsset = _phases.last.onAsset;
-    _onDone = _phases.last.onDone;
+    _onStatusChange = _phases.last.onStatusChange;
   }
 
   /// Add a phase with [contents] to [this]'s list of phases.
   ///
   /// [contents] should be an inner [Iterable] from a [TransformGroup.phases]
   /// value.
   void _addPhase(Phase phase, Iterable contents) {
     _phases.add(phase);
     _onLogPool.add(phase.onLog);
     phase.updateTransformers(contents);
@@ skipping 15 matching lines @@
   /// Removes this group and all sub-phases within it.
   void remove() {
     _onLogPool.close();
     for (var phase in _phases) {
       phase.remove();
     }
   }
 
   String toString() => "group in phase $_location for $_group";
 }