Add Future.doWhile to dart:async.

tests/lib/async/futures_test.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.
 
 library futures_test;
 import 'package:async_helper/async_helper.dart';
 import "package:expect/expect.dart";
 import 'dart:async';
 
 Future testWaitEmpty() {
@@ skipping 166 matching lines @@
 }
 
 Future testForEach() {
   var seen = <int>[];
   return Future.forEach([1, 2, 3, 4, 5], (n) {
     seen.add(n);
     return new Future.value();
   }).then((_) => Expect.listEquals([1, 2, 3, 4, 5], seen));
 }
 
+Future testForEachSync() {
+  var seen = <int>[];
+  return Future.forEach([1, 2, 3, 4, 5], seen.add)
+      .then((_) => Expect.listEquals([1, 2, 3, 4, 5], seen));
+}
+
 Future testForEachWithException() {
   var seen = <int>[];
   return Future.forEach([1, 2, 3, 4, 5], (n) {
     if (n == 4) throw 'correct exception';
     seen.add(n);
     return new Future.value();
   }).then((_) {
     throw 'incorrect exception';
   }).catchError((error) {
     Expect.equals('correct exception', error);
   });
 }
 
+Future testDoWhile() {
+  var count = 0;
+  return Future.doWhile(() {
+    count++;
+    return new Future(() => count < 10);
+  }).then((_) => Expect.equals(10, count));
+}
+
+Future testDoWhileSync() {
+  var count = 0;
+  return Future.doWhile(() {
+    count++;
+    return count < 10;
+  }).then((_) => Expect.equals(10, count));
+}
+
+Future testDoWhileWithException() {
+  var count = 0;
+  return Future.doWhile(() {
+    count++;
+    if (count == 4) throw 'correct exception';
+    return new Future(() => true);
+  }).then((_) {
+    throw 'incorrect exception';
+  }).catchError((error) {
+    Expect.equals('correct exception', error);
+  });
+}
+
 main() {
   List<Future> futures = new List<Future>();
 
   futures.add(testWaitEmpty());
   futures.add(testCompleteAfterWait());
   futures.add(testCompleteBeforeWait());
   futures.add(testWaitWithMultipleValues());
   futures.add(testWaitWithSingleError());
   futures.add(testWaitWithMultipleErrors());
   futures.add(testWaitWithMultipleErrorsEager());
   futures.add(testWaitWithSingleErrorWithStackTrace());
   futures.add(testWaitWithMultipleErrorsWithStackTrace());
   futures.add(testWaitWithMultipleErrorsWithStackTraceEager());
   futures.add(testEagerWait());
   futures.add(testForEachEmpty());
   futures.add(testForEach());
+  futures.add(testForEachSync());
   futures.add(testForEachWithException());
+  futures.add(testDoWhile());
+  futures.add(testDoWhileSync());
+  futures.add(testDoWhileWithException());
 
   asyncStart();
   Future.wait(futures).then((List list) {
-    Expect.equals(14, list.length);
+    Expect.equals(18, list.length);
     asyncEnd();
   });
 }