Refactor groups to pipe them through to the runner.

lib/src/runner/loader.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 test.runner.loader;
 
 import 'dart:async';
 import 'dart:io';
 import 'dart:isolate';
 
 import 'package:analyzer/analyzer.dart';
 import 'package:async/async.dart';
 import 'package:path/path.dart' as p;
 import 'package:stack_trace/stack_trace.dart';
 
 import '../backend/invoker.dart';
+import '../backend/group.dart';
 import '../backend/metadata.dart';
+import '../backend/suite_entry.dart';
 import '../backend/test_platform.dart';
 import '../util/dart.dart' as dart;
 import '../util/io.dart';
 import '../util/remote_exception.dart';
 import '../utils.dart';
 import 'browser/server.dart';
 import 'configuration.dart';
 import 'hack_load_vm_file_hook.dart';
 import 'load_exception.dart';
 import 'load_suite.dart';
@@ skipping 184 matching lines @@
             new LoadException(path, response["message"]),
             new Trace.current());
       } else if (response["type"] == "error") {
         isolate.kill();
         var asyncError = RemoteException.deserialize(response["error"]);
         completer.completeError(
             new LoadException(path, asyncError.error),
             asyncError.stackTrace);
       } else {
         assert(response["type"] == "success");
-        completer.complete(response["tests"]);
+        completer.complete(response["entries"]);
       }
     });
 
     try {
-      var suite = new RunnerSuite(const VMEnvironment(),
-          (await completer.future).map((test) {
-        var testMetadata = new Metadata.deserialize(test['metadata']);
-        return new IsolateTest(test['name'], testMetadata, test['sendPort']);
-      }),
+      var suite = new RunnerSuite(
+          const VMEnvironment(),
+          _deserializeEntries(await completer.future),
           metadata: metadata,
           path: path,
           platform: TestPlatform.vm,
           os: currentOS,
           onClose: isolate.kill);
       _suites.add(suite);
       return suite;
     } finally {
       subscription.cancel();
     }
   }
 
+  /// Deserializes [entries] into concrete [SuiteEntry] subclasses.
+  Iterable<SuiteEntry> _deserializeEntries(List<Map> entries) {
+    return entries.map((entry) {
+      var metadata = new Metadata.deserialize(entry['metadata']);
+      if (entry['type'] == 'group') {
+        return new Group(
+            entry['name'], metadata, _deserializeEntries(entry['entries']));
+      } else {
+        return new IsolateTest(entry['name'], metadata, entry['sendPort']);
+      }
+    });
+  }
+
   /// Closes the loader and releases all resources allocated by it.
   Future close() {
     return _closeMemo.runOnce(() async {
       await Future.wait(_suites.map((suite) => suite.close()));
       _suites.clear();
 
       if (!_browserServerMemo.hasRun) return;
       await (await _browserServer).close();
     });
   }
 }