| // Copyright (c) 2014, 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 shelf.util; |
| |
| import 'dart:async'; |
| |
| import 'package:stack_trace/stack_trace.dart'; |
| |
| /// Like [new Future], but avoids around issue 11911 by using [new Future.value] |
| /// under the covers. |
| Future newFuture(callback()) => new Future.value().then((_) => callback()); |
| |
| /// Like [Future.sync], but wraps the Future in [Chain.track] as well. |
| Future syncFuture(callback()) => Chain.track(new Future.sync(callback)); |
| |
| /// Run [callback] and capture any errors that would otherwise be top-leveled. |
| /// |
| /// If [this] is called in a non-root error zone, it will just run [callback] |
| /// and return the result. Otherwise, it will capture any errors using |
| /// [runZoned] and pass them to [onError]. |
| catchTopLevelErrors(callback(), void onError(error, StackTrace stackTrace)) { |
| if (Zone.current.inSameErrorZone(Zone.ROOT)) { |
| return runZoned(callback, onError: onError); |
| } else { |
| return callback(); |
| } |
| } |
| |
| /// Returns a [Map] with the values from [original] and the values from |
| /// [updates]. |
| /// |
| /// For keys that are the same between [original] and [updates], the value in |
| /// [updates] is used. |
| /// |
| /// If [updates] is `null` or empty, [original] is returned unchanged. |
| Map updateMap(Map original, Map updates) { |
| if (updates == null || updates.isEmpty) return original; |
| |
| return new Map.from(original)..addAll(updates); |
| } |