Add a new kind of suite to ease test.dart integration.

pkg/testing/lib/src/run.dart

 // Copyright (c) 2016, 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.md file.
 
 library testing.run;
 
 import 'dart:async' show
     Future,
     Stream;
 
@@ skipping 31 matching lines @@
 import 'log.dart' show
     isVerbose,
     logMessage,
     logNumberedLines,
     splitLines;
 
 import 'suite.dart' show
     Dart,
     Suite;
 
+import 'test_dart.dart' show
+    TestDart;
+
 import 'zone_helper.dart' show
     acknowledgeControlMessages;
 
 Future<TestRoot> computeTestRoot(String configurationPath, Uri base) {
   Uri configuration = configurationPath == null
       ? Uri.base.resolve("testing.json")
       : base.resolve(configurationPath);
   return TestRoot.fromUri(configuration);
 }
 
@@ skipping 110 matching lines @@
       description.writeImportOn(imports);
       description.writeClosureOn(dart);
     }
 
     for (Chain suite in suites.where((Suite suite) => suite is Chain)) {
       testUris.add(await Isolate.resolvePackageUri(suite.source));
       suite.writeImportOn(imports);
       suite.writeClosureOn(chain);
     }
 
-    if (testUris.isEmpty) return null;
+    bool hasTestDartSuite = false;
+    for (TestDart suite in suites.where((Suite suite) => suite is TestDart)) {
+      if (!hasTestDartSuite) {
+        suite.writeFirstImportOn(imports);
+      }
+      hasTestDartSuite = true;
+      suite.writeRunCommandOn(chain);
+    }
+
+    if (testUris.isEmpty && !hasTestDartSuite) return null;
 
     return """
 library testing.generated;
 
 import 'dart:async' show Future;
 
 import 'dart:convert' show JSON;
 
 import 'package:testing/src/run_tests.dart' show runTests;
 
@@ skipping 27 matching lines @@
                      listTests(<Uri>[suite.uri], pattern: "")) {
         String path = description.file.uri.path;
         if (suite.exclude.any((RegExp r) => path.contains(r))) continue;
         if (suite.pattern.any((RegExp r) => path.contains(r))) {
           yield description;
         }
       }
     }
   }
 }