Added the ability to filter which tests are run by name, using a --filter

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 196 matching lines @@
 String _uncaughtErrorMessage = null;
 
 final _PASS  = 'pass';
 final _FAIL  = 'fail';
 final _ERROR = 'error';
 
 /** If set, then all other test cases will be ignored. */
 TestCase _soloTest;
 
 /**
+ * If set, then only tests whose descriptions match this regexp pattern
+ * will be run.
+ */
+String _filter = null;
+
+/**
  * (Deprecated) Evaluates the [function] and validates that it throws an
  * exception. If [callback] is provided, then it will be invoked with the
  * thrown exception. The callback may do any validation it wants. In addition,
  * if it returns `false`, that also indicates an expectation failure.
  */
 void expectThrow(function, [bool callback(exception)]) {
   bool threw = false;
   try {
     function();
   } catch (var e) {
     threw = true;
 
     // Also let the callback look at it.
     if (callback != null) {
       var result = callback(e);
 
       // If the callback explicitly returned false, treat that like an
       // expectation too. (If it returns null, though, don't.)
       if (result == false) {
         _fail('Exception:\n$e\ndid not match expectation.');
       }
     }
   }
 
   if (threw != true) _fail('An expected exception was not thrown.');
 }
 
 /**
+ * Sets the regexp pattern filter which constrains which tests to run
+ * based on their descriptions.
+ */
+void setFilter(String filter) {
+  if (filter == '') filter = null;
+  _filter = filter;
+}
+
+/**
+ * Gets the regexp pattern filter which constrains which tests to run
+ * based on their descriptions.
+ */
+String getFilter() {
+  return _filter;
+}
+/**
  * Creates a new test case with the given description and body. The
  * description will include the descriptions of any surrounding group()
  * calls.
  */
 void test(String spec, TestFunction body) {
   ensureInitialized();
 
   _tests.add(new TestCase(_tests.length + 1, _fullSpec(spec), body, 0));
 }
 
@@ skipping 373 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);
 }
 
+/** Check arguments for a --filter spec. */
+_getFilterFromArgs() {
+  var options = new Options().arguments;
+  if (options != null) {
+    for (var i = 0; i < options.length; i++) {
+      if (options[i].startsWith('--filter=')) {
+        var filter = options[i].substring(9);
+        if (filter.length > 0) {
+          // Strip quotes if present.
+          var last = filter.length - 1;
+          if ((filter[0] == "'" && filter[last] == "'") ||
+              (filter[0] == '"' && filter[last] == '"')) {
+            filter = filter.substring(1, last);
+          }
+          if (filter.length > 0) {
+            setFilter(filter);
+          }
+        }
+        break;
+      }
+    }
+  }
+}
+
 /** Runs all queued tests, one at a time. */
 _runTests() {
   // If we are soloing a test, remove all the others.
   if (_soloTest != null) {
     _tests = _tests.filter((t) => t == _soloTest);
   }
+  if (_filter == null) {
+    _getFilterFromArgs();
+  }
+  if (_filter != null) {
+    RegExp re = new RegExp(_filter);
+    _tests = _tests.filter((t) => re.hasMatch(t.description));
+  }
 
   _config.onStart();
 
   _defer(() {
     assert (_currentTest == 0);
     _testRunner();
   });
 }
 
 /**
@@ skipping 102 matching lines @@
   _config.onInit();
 
   // Immediately queue the suite up. It will run after a timeout (i.e. after
   // main() has returned).
   _defer(_runTests);
 }
 
 /** Signature for a test function. */
 typedef void TestFunction();