| // Copyright (c) 2015, 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 Execution of a for-in statement of the form await for |
| /// (finalConstVarOrType? id in e) s proceeds as follows: |
| /// The expression e is evaluated to an object o. It is a dynamic error if o |
| /// is not an instance of a class that implements Stream. Otherwise, |
| /// the expression await vf is evaluated, where vf is a fresh variable |
| /// whose value is a fresh instance f implementing the built-in class Future. |
| /// The stream o is listened to, and on each data event in o |
| /// the statement s is executed with id bound to the value of the current |
| /// element of the stream. If s raises an exception, or if o raises |
| /// an exception, then f is completed with that exception. Otherwise, when |
| /// all events in the stream o have been processed, f is completed with null. |
| /// |
| /// @description Check that if o raises an exception, then asynchronous for-in |
| /// statement is completed with that exception. |
| /// |
| /// @issue 24766 |
| /// @issue 24748 |
| /// @author a.semenov@unipro.ru |
| |
| import 'dart:async'; |
| import '../../../../Utils/expect.dart'; |
| |
| final ERROR = new Exception(); |
| |
| Future<int> f() async { |
| throw ERROR; |
| } |
| |
| Future test1() async { |
| var processedValues = []; |
| try { |
| await for (var i in f().asStream()) { |
| processedValues.add(i); |
| } |
| Expect.fail("Asynchronous for-in statement should throw $ERROR"); |
| } catch (e) { |
| Expect.identical(ERROR, e); |
| } |
| Expect.listEquals([], processedValues); |
| } |
| |
| int computation(int computationCount) { |
| if (computationCount < 5) { |
| return computationCount; |
| } |
| throw ERROR; |
| } |
| |
| Future test2() async { |
| var processedValues = []; |
| var period = new Duration(microseconds: 1); |
| try { |
| await for (var i in new Stream.periodic(period, computation)) { |
| processedValues.add(i); |
| } |
| Expect.fail("Asynchronous for-in statement should throw $ERROR"); |
| } catch (e) { |
| Expect.identical(ERROR, e); |
| } |
| Expect.listEquals([0, 1, 2, 3, 4], processedValues); |
| } |
| |
| // try an already closed single subscription stream |
| Future test3() async { |
| // make a stream that is closed |
| Stream stream = new Stream.fromIterable([1, 2]); |
| await for (var x in stream) { |
| } |
| var processedValues = []; |
| try { |
| await for (var i in stream) { |
| processedValues.add(i); |
| } |
| Expect.fail("Asynchronous for-in statement should complete with error"); |
| } catch (e) { |
| // the exception type is not specified |
| // neither in Dart Language Specification nor in Dart Async API |
| // (see issue 24748) |
| // so just catch it |
| } |
| Expect.isTrue(processedValues.isEmpty); |
| } |
| |
| |
| main() { |
| asyncStart(); |
| Future.wait([test1(), test2(), test3()]).then((v) => asyncEnd()); |
| } |