| // Copyright (c) 2013, 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. |
| |
| /// @assertion Iterable map(f(E element)) |
| /// As long as the returned [Iterable] is not iterated over, |
| /// the supplied function [f] will not be invoked. |
| /// @description Checks that [f] will not be invoked until |
| /// the returned [Iterable] is not iterated over. |
| /// @author msyabro |
| |
| import "../../../Utils/expect.dart"; |
| |
| main() { |
| bool invoked = false; |
| f(e) { |
| invoked = true;; |
| return e; |
| } |
| |
| var runes = new Runes('_'); |
| var res = runes.map(f); |
| |
| Expect.isFalse(invoked); |
| res.elementAt(0); |
| Expect.isTrue(invoked); |
| } |