Make [Barback.getAllAssets] work when called synchronously.

pkg/barback/test/utils.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.test.utils;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:convert' show Encoding;
 
@@ skipping 60 matching lines @@
 /// [AssetId] and the value should be a string defining the contents of that
 /// asset.
 ///
 /// [transformers] is a map from package names to the transformers for each
 /// package.
 void initGraph([assets,
     Map<String, Iterable<Iterable<Transformer>>> transformers]) {
   if (assets == null) assets = [];
   if (transformers == null) transformers = {};
 
-  var assetList;
-  if (assets is Map) {
-    assetList = assets.keys.map((asset) {
-      var id = new AssetId.parse(asset);
-      return new _MockAsset(id, assets[asset]);
-    });
-  } else if (assets is Iterable) {
-    assetList = assets.map((asset) {
-      var id = new AssetId.parse(asset);
-      var contents = pathos.basenameWithoutExtension(id.path);
-      return new _MockAsset(id, contents);
-    });
-  }
-
-  var assetMap = mapMapValues(groupBy(assetList, (asset) => asset.id.package),
-      (package, assets) => new AssetSet.from(assets));
-
-  // Make sure that packages that have transformers but no assets are considered
-  // by MockProvider to exist.
-  for (var package in transformers.keys) {
-    assetMap.putIfAbsent(package, () => new AssetSet());
-  }
-
-  _provider = new MockProvider(assetMap);
+  _provider = new MockProvider(assets, additionalPackages: transformers.keys);
   _barback = new Barback(_provider);
   // Add a dummy listener to the log so it doesn't print to stdout.
   _barback.log.listen((_) {});
   _nextBuildResult = 0;
   _nextLog = 0;
 
   schedule(() => transformers.forEach(_barback.updateTransformers));
 
   // There should be one successful build after adding all the transformers but
   // before adding any sources.
@@ skipping 362 matching lines @@
     currentSchedule.signalError(error);
   });
 
   return delay.then((_) => cancelable.cancel());
 }
 
 /// An [AssetProvider] that provides the given set of assets.
 class MockProvider implements PackageProvider {
   Iterable<String> get packages => _assets.keys;
 
-  Map<String, AssetSet> _assets;
+  final Map<String, AssetSet> _assets;
 
   /// The set of assets for which [MockLoadException]s should be emitted if
   /// they're loaded.
   final _errors = new Set<AssetId>();
 
   /// The completer that [getAsset()] is waiting on to complete when paused.
   ///
   /// If `null` it will return the asset immediately.
   Completer _pauseCompleter;
 
   /// Tells the provider to wait during [getAsset] until [complete()]
   /// is called.
   ///
   /// Lets you test the asynchronous behavior of loading.
   void _pause() {
     _pauseCompleter = new Completer();
   }
 
   void _resume() {
     _pauseCompleter.complete();
     _pauseCompleter = null;
   }
 
-  MockProvider(this._assets) {
+  MockProvider(assets, {Iterable<String> additionalPackages})
+      : _assets = _normalizeAssets(assets, additionalPackages);
+
+  static Map<String, AssetSet> _normalizeAssets(assets,
+      Iterable<String> additionalPackages) {
+    var assetList;
+    if (assets is Map) {
+      assetList = assets.keys.map((asset) {
+        var id = new AssetId.parse(asset);
+        return new _MockAsset(id, assets[asset]);
+      });
+    } else if (assets is Iterable) {
+      assetList = assets.map((asset) {
+        var id = new AssetId.parse(asset);
+        var contents = pathos.basenameWithoutExtension(id.path);
+        return new _MockAsset(id, contents);
+      });
+    }
+
+    var assetMap = mapMapValues(groupBy(assetList, (asset) => asset.id.package),
+        (package, assets) => new AssetSet.from(assets));
+
+    // Make sure that packages that have transformers but no assets are
+    // considered by MockProvider to exist.
+    if (additionalPackages != null) {
+      for (var package in additionalPackages) {
+        assetMap.putIfAbsent(package, () => new AssetSet());
+      }
+    }
+
     // If there are no assets or transformers, add a dummy package. This better
     // simulates the real world, where there'll always be at least the
     // entrypoint package.
-    if (_assets.isEmpty) {
-      _assets = {"app": new AssetSet()};
-    }
+    return assetMap.isEmpty ? {"app": new AssetSet()} : assetMap;
   }
 
   void _modifyAsset(String name, String contents) {
     var id = new AssetId.parse(name);
     _errors.remove(id);
     (_assets[id.package][id] as _MockAsset).contents = contents;
   }
 
   void _setAssetError(String name) {
     _errors.add(new AssetId.parse(name));
@@ skipping 47 matching lines @@
 
   _MockAsset(this.id, this.contents);
 
   Future<String> readAsString({Encoding encoding}) =>
       new Future.value(contents);
 
   Stream<List<int>> read() => throw new UnimplementedError();
 
   String toString() => "MockAsset $id $contents";
 }