starting to work on unit test config interface

pkg/unittest/lib/unittest.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.
 
 /**
  * A library for writing dart unit tests.
  *
  * ## Installing ##
  *
  * Use [pub][] to install this package. Add the following to your `pubspec.yaml`
@@ skipping 128 matching lines @@
  * [Issue 2706](http://dartbug.com/2706)).
  *
  * [pub]: http://pub.dartlang.org
  * [pkg]: http://pub.dartlang.org/packages/unittest
  */
 library unittest;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:isolate';
+import 'package:stack_trace/stack_trace.dart';
+
 import 'matcher.dart';
 export 'matcher.dart';
 
-import 'package:stack_trace/stack_trace.dart';
+import 'src/utils.dart';
 
-import 'src/utils.dart';
-part 'src/config.dart';
+part 'src/configuration.dart';
+part 'src/simple_configuration.dart';
 part 'src/test_case.dart';
 
 Configuration _config;
 
 /**
  * [Configuration] used by the unittest library. Note that if a
  * configuration has not been set, calling this getter will create
  * a default configuration.
  */
 Configuration get unittestConfiguration {
@@ skipping 483 matching lines @@
 void tearDown(Function teardownTest) {
   _currentContext.testTeardown = teardownTest;
 }
 
 /** Advance to the next test case. */
 void _nextTestCase() {
   _currentTestCaseIndex++;
   _runTest();
 }
 
-/**
- * Utility function that can be used to notify the test framework that an
- *  error was caught outside of this library.
- */
-void _reportTestError(String msg, trace) {
- if (_currentTestCaseIndex < testCases.length) {
-    final testCase = testCases[_currentTestCaseIndex];
-    testCase.error(msg, trace);
+/** Handle errors that happen outside the tests. */
+// TODO(vsm): figure out how to expose the stack trace here
+// Currently e.message works in dartium, but not in dartc.
+void handleExternalError(e, String message, [stack]) {
+  var msg = '$message\nCaught $e';
+
+  if (currentTestCase != null) {
+    currentTestCase.error(msg, stack);
   } else {
-    _uncaughtErrorMessage = "$msg: $trace";
+    _uncaughtErrorMessage = "$msg: $stack";
   }
 }
 
 void rerunTests() {
   _uncaughtErrorMessage = null;
   _initialized = true; // We don't want to reset the test array.
   runTests();
 }
 
 /**
@@ skipping 185 matching lines @@
 
   if (!formatStacks) return trace;
 
   // Format the stack trace by removing everything above TestCase._runTest,
   // which is usually going to be irrelevant. Also fold together unittest and
   // core library calls so only the function the user called is visible.
   return new Trace(trace.frames.takeWhile((frame) {
     return frame.package != 'unittest' || frame.member != 'TestCase._runTest';
   })).terse.foldFrames((frame) => frame.package == 'unittest' || frame.isCore);
 }