Abort unit tests in the event of async failure while awaiting a future.

pkg/unittest/lib/src/test_case.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.
 
 part of unittest;
 
 /// Represents the state for an individual unit test.
 ///
 /// Create by calling [test] or [solo_test].
 class TestCase {
@@ skipping 81 matching lines @@
     // Avoid calling [new Future] to avoid issue 11911.
     return new Future.value().then((_) {
       if (_setUp != null) return _setUp();
     }).catchError(_errorHandler('Setup')).then((_) {
       // Skip the test if setup failed.
       if (result != null) return new Future.value();
       _config.onTestStart(this);
       _startTime = new DateTime.now();
       _runningTime = null;
       ++_callbackFunctionsOutstanding;
-      return _testFunction();
+      var testReturn = _testFunction();
+      // If _testFunction() returned a future, we want to wait for it like we
+      // would a callback, so if a failure occurs while waiting, we can abort.
+      if (testReturn is Future) {
+        ++_callbackFunctionsOutstanding;
+        testReturn.catchError(_errorHandler('Test'))
+            .whenComplete(_markCallbackComplete);
+      }
     }).catchError(_errorHandler('Test')).then((_) {
       _markCallbackComplete();
       if (result == null) {
         // Outstanding callbacks exist; we need to return a Future.
         _testComplete = new Completer();
         return _testComplete.future.whenComplete(() {
           if (_tearDown != null) {
             return _tearDown();
           }
         }).catchError(_errorHandler('Teardown'));
@@ skipping 58 matching lines @@
   }
 
   void _markCallbackComplete() {
     if (--_callbackFunctionsOutstanding == 0 && !isComplete) {
       _pass();
     }
   }
 
   String toString() => _result != null ? "$description: $result" : description;
 }