Reverted a couple of earlier cleanups to the unittest framework. They introduced issues with cases …

lib/unittest/unittest.dart

 // Copyright (c) 2011, 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.
  *
  * To import this library, specify the relative path to
  * lib/unittest/unittest.dart.
  *
@@ skipping 667 matching lines @@
   // message at the end of the event loop.
   // TODO(sigmund): expose this functionality somewhere in our libraries.
   final port = new ReceivePort();
   port.receive((msg, reply) {
     callback();
     port.close();
   });
   port.toSendPort().send(null, null);
 }
 
+rerunTests() {
+  _uncaughtErrorMessage = null;
+  runTests();
+}
+
 /** Runs all queued tests, one at a time. */
 runTests() {
-  _uncaughtErrorMessage = null;
   _currentTest = 0;
   _currentGroup = '';
 
   // If we are soloing a test, remove all the others.
   if (_soloTest != null) {
     _tests = _tests.filter((t) => t == _soloTest);
   }
 
   if (filter != null) {
     RegExp re = new RegExp(filter);
     _tests = _tests.filter((t) => re.hasMatch(t.description));
   }
 
   _config.onStart();
 
   _defer(() {
-    expect(_currentTest, isZero);
     _testRunner();
   });
 }
 
 /**
  * Run [tryBody] guarded in a try-catch block. If an exception is thrown, update
  * the [_currentTest] status accordingly.
  */
 guardAsync(tryBody, [finallyBody, testNum = -1]) {
   if (testNum < 0) testNum = _currentTest;
   try {
     return tryBody();
   } catch (var e, var trace) {
     registerException(testNum, e, trace);
   } finally {
     if (finallyBody != null) finallyBody();
   }
 }
 
 /**
  * Registers that an exception was caught for the current test.
  */
 registerException(testNum, e, [trace]) {
   trace = trace == null ? '' : trace.toString();
   if (_tests[testNum].result == null) {
-    if (e is ExpectException) {
-      _tests[testNum].fail(e.message, trace);
-    } else {
-      _tests[testNum].fail('Caught $e', trace);
-    }
+    String message = (e is ExpectException) ? e.message : 'Caught $e';
+    _tests[testNum].fail(message, trace);
   } else {
     _tests[testNum].error('Caught $e', trace);
   }
   if (testNum == _currentTest) {
     _nextTestCase();
   }
 }
 
 /**
  * Runs a batch of tests, yielding whenever an asynchronous test starts
@@ skipping 24 matching lines @@
   int testsFailed_ = 0;
   int testsErrors_ = 0;
 
   for (TestCase t in _tests) {
     switch (t.result) {
       case _PASS:  testsPassed_++; break;
       case _FAIL:  testsFailed_++; break;
       case _ERROR: testsErrors_++; break;
     }
   }
-
   _config.onDone(testsPassed_, testsFailed_, testsErrors_, _tests,
       _uncaughtErrorMessage);
   _initialized = false;
 }
 
 String _fullSpec(String spec) {
   if (spec === null) return '$_currentGroup';
   return _currentGroup != '' ? '$_currentGroup $spec' : spec;
 }
 
 void _fail(String message) {
   throw new ExpectException(message);
 }
 
 /**
  * Lazily initializes the test library if not already initialized.
  */
 ensureInitialized() {
   if (_initialized) return;
   _initialized = true;
 
   _tests = <TestCase>[];
   _testRunner = _nextBatch;
+  _uncaughtErrorMessage = null;
 
   if (_config == null) {
     _config = new Configuration();
   }
   _config.onInit();
 
   if (_config.autoStart) {
     // Immediately queue the suite up. It will run after a timeout (i.e. after
     // main() has returned).
     _defer(runTests);
@@ skipping 26 matching lines @@
 }
 
 /** Enable a test by ID. */
 void enableTest(int testId) => _setTestEnabledState(testId, true);
 
 /** Disable a test by ID. */
 void disableTest(int testId) => _setTestEnabledState(testId, false);
 
 /** Signature for a test function. */
 typedef void TestFunction();