Change Future.doWhile to use a loop for non-future results instead of recursion.

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';
 
@@ skipping 220 matching lines @@
     count++;
     if (count == 4) throw 'correct exception';
     return new Future(() => true);
   }).then((_) {
     throw 'incorrect exception';
   }).catchError((error) {
     Expect.equals('correct exception', error);
   });
 }
 
+Future testDoWhileManyFutures() {
+  int n = 100000;
+  var ftrue = new Future.value(false);
+  var ffalse = new Future.value(false);
+  return Future.doWhile(() {
+    return (--n > 0) ? ftrue : ffalse;
+  }).then((_) {
+    // Success
+  }, onError: (e, s) {
+    Expect.fail("$e\n$s");
+  });
+}
+
+Future testDoWhileManyValues() {
+  int n = 100000;
+  return Future.doWhile(() {
+    return (--n > 0);
+  }).then((_) {
+    // Success
+  }, onError: (e, s) {
+    Expect.fail("$e\n$s");
+  });
+}
+
 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());
+  futures.add(testDoWhileManyFutures());
+  futures.add(testDoWhileManyValues());
 
   asyncStart();
   Future.wait(futures).then((List list) {
-    Expect.equals(18, list.length);
+    Expect.equals(20, list.length);
     asyncEnd();
   });
 }