Pass logs through transformer groups.

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 17 matching lines @@
 var _configured = false;
 
 MockProvider _provider;
 Barback _barback;
 
 /// Calls to [buildShouldSucceed] and [buildShouldFail] set expectations on
 /// successive [BuildResult]s from [_barback]. This keeps track of how many
 /// calls have already been made so later calls know which result to look for.
 int _nextBuildResult;
 
+/// Calls to [buildShouldLog] set expectations on successive log entries from
+/// [_barback]. This keeps track of how many calls have already been made so
+/// later calls know which result to look for.
+int _nextLog;
+
 void initConfig() {
   if (_configured) return;
   _configured = true;
   useCompactVMConfiguration();
   filterStacks = true;
 }
 
 /// Creates a new [PackageProvider] and [PackageGraph] with the given [assets]
 /// and [transformers].
 ///
@@ skipping 33 matching lines @@
 
   // 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);
   _barback = new Barback(_provider);
   _nextBuildResult = 0;
+  _nextLog = 0;
 
   transformers.forEach(_barback.updateTransformers);
 
   // There should be one successful build after adding all the transformers but
   // before adding any sources.
   if (!transformers.isEmpty) buildShouldSucceed();
 }
 
 /// Updates [assets] in the current [PackageProvider].
 ///
@@ skipping 108 matching lines @@
 void buildShouldFail(List matchers) {
   expect(_getNextBuildResult("build should fail").then((result) {
     expect(result.succeeded, isFalse);
     expect(result.errors.length, equals(matchers.length));
     for (var matcher in matchers) {
       expect(result.errors, contains(matcher));
     }
   }), completes);
 }
 
+/// Expects that the nexted logged [LogEntry] matches [matcher] which may be
+/// either a [Matcher] or a string to match a literal string.
+void buildShouldLog(LogLevel level, matcher) {
+  expect(_getNextLog("build should log").then((log) {
+    expect(log.level, equals(level));
+    expect(log.message, matcher);
+  }), completes);
+}
+
 Future<BuildResult> _getNextBuildResult(String description) {
   var result = currentSchedule.wrapFuture(
       _barback.results.elementAt(_nextBuildResult++));
   return schedule(() => result, description);
 }
 
+Future<LogEntry> _getNextLog(String description) {
+  var result = currentSchedule.wrapFuture(
+      _barback.log.elementAt(_nextLog++));
+  return schedule(() => result, description);
+}
+
 /// Schedules an expectation that the graph will deliver an asset matching
 /// [name] and [contents].
 ///
 /// If [contents] is omitted, defaults to the asset's filename without an
 /// extension (which is the same default that [initGraph] uses).
 void expectAsset(String name, [String contents]) {
   var id = new AssetId.parse(name);
 
   if (contents == null) {
     contents = pathos.basenameWithoutExtension(id.path);
@@ skipping 286 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";
 }