Run pub tests against older versions of barback.

third_party/pkg/barback-0.13.0/lib/src/asset_cascade.dart

Index: third_party/pkg/barback-0.13.0/lib/src/asset_cascade.dart
diff --git a/pkg/barback/lib/src/graph/asset_cascade.dart b/third_party/pkg/barback-0.13.0/lib/src/asset_cascade.dart
similarity index 84%
copy from pkg/barback/lib/src/graph/asset_cascade.dart
copy to third_party/pkg/barback-0.13.0/lib/src/asset_cascade.dart
index ca087857311d0197562301fec645e468ecba74a7..74db0d9766e3976eab56010cc94ef20d89957a3d 100644
--- a/pkg/barback/lib/src/graph/asset_cascade.dart
+++ b/third_party/pkg/barback-0.13.0/lib/src/asset_cascade.dart
@@ -2,22 +2,21 @@
 // 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.graph.asset_cascade;
+library barback.asset_cascade;
 
 import 'dart:async';
 
-import '../asset/asset.dart';
-import '../asset/asset_id.dart';
-import '../asset/asset_node.dart';
-import '../asset/asset_set.dart';
-import '../errors.dart';
-import '../log.dart';
-import '../transformer/transformer.dart';
-import '../utils/cancelable_future.dart';
-import 'node_status.dart';
-import 'node_streams.dart';
+import 'asset.dart';
+import 'asset_id.dart';
+import 'asset_node.dart';
+import 'asset_set.dart';
+import 'log.dart';
+import 'cancelable_future.dart';
+import 'errors.dart';
 import 'package_graph.dart';
 import 'phase.dart';
+import 'stream_pool.dart';
+import 'transformer.dart';
 
 /// The asset cascade for an individual package.
 ///
@@ -56,9 +55,9 @@ class AssetCascade {
   /// request inputs from a previous phase.
   final _phases = <Phase>[];
 
-  /// The subscription to the [Phase.onStatusChange] stream of the last [Phase]
-  /// in [_phases].
-  StreamSubscription _phaseStatusSubscription;
+  /// The subscription to the [Phase.onDone] stream of the last [Phase] in
+  /// [_phases].
+  StreamSubscription _phaseOnDoneSubscription;
 
   /// A stream that emits any errors from the cascade or the transformers.
   ///
@@ -68,17 +67,24 @@ class AssetCascade {
   final _errorsController =
       new StreamController<BarbackException>.broadcast(sync: true);
 
-  /// How far along [this] is in processing its assets.
-  NodeStatus get status {
+  /// A stream that emits an event whenever any transforms in this cascade logs
+  /// an entry.
+  Stream<LogEntry> get onLog => _onLogPool.stream;
+  final _onLogPool = new StreamPool<LogEntry>.broadcast();
+
+  /// Whether [this] is dirty and still has more processing to do.
+  bool get isDirty {
     // Just check the last phase, since it will check all the previous phases
     // itself.
-    return _phases.last.status;
+    return _phases.last.isDirty;
   }
 
-  /// The streams exposed by this cascade.
-  final _streams = new NodeStreams();
-  Stream<LogEntry> get onLog => _streams.onLog;
-  Stream<NodeStatus> get onStatusChange => _streams.onStatusChange;
+  /// 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 => _onDoneController.stream;
+  final _onDoneController = new StreamController.broadcast(sync: true);
 
   /// Returns all currently-available output assets from this cascade.
   AssetSet get availableOutputs =>
@@ -191,9 +197,9 @@ class AssetCascade {
     }
     _phases.removeRange(transformers.length + 1, _phases.length);
 
-    _phaseStatusSubscription.cancel();
-    _phaseStatusSubscription = _phases.last.onStatusChange
-        .listen(_streams.changeStatus);
+    _phaseOnDoneSubscription.cancel();
+    _phaseOnDoneSubscription = _phases.last.onDone
+        .listen(_onDoneController.add);
   }
 
   /// Force all [LazyTransformer]s' transforms in this cascade to begin
@@ -210,10 +216,9 @@ class AssetCascade {
 
   /// Add [phase] to the end of [_phases] and watch its streams.
   void _addPhase(Phase phase) {
-    _streams.onLogPool.add(phase.onLog);
-    if (_phaseStatusSubscription != null) _phaseStatusSubscription.cancel();
-    _phaseStatusSubscription =
-        phase.onStatusChange.listen(_streams.changeStatus);
+    _onLogPool.add(phase.onLog);
+    if (_phaseOnDoneSubscription != null) _phaseOnDoneSubscription.cancel();
+    _phaseOnDoneSubscription = phase.onDone.listen(_onDoneController.add);
 
     _phases.add(phase);
   }