dart-sdk/tests/language_2/async_star_error_test.dart
Jenny Messerly 106d6b0ca5 [dartdevc] fix #29847 async* dropping errors in some cases
This happened using APIs like `Stream.first` that set cancelOnError when
they called `Stream.listen()`. If an error is signaled, Stream internals
will call `cancel()` and wait for that future to complete before sending
the error to the resulting Future. However the `async*` implementation
class did not properly account for that possiblity, and never completed
the cancellation future in that case.

Change-Id: Ieaa35e56ee80208d7946904ea40bfd5f785ef9d6
Reviewed-on: https://dart-review.googlesource.com/c/83467
Commit-Queue: Alan Knight <alanknight@google.com>
Auto-Submit: Jenny Messerly <jmesserly@google.com>
Reviewed-by: Alan Knight <alanknight@google.com>
2018-11-08 05:04:23 +00:00

34 lines
879 B
Dart

// Copyright (c) 2018, 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.
import "dart:async";
import "package:expect/async_minitest.dart";
/// Tests for exceptions raised in async*
main() {
test('async* with Stream.first should complete with an error', () async {
var expectedStack;
Stream<int> foo() async* {
try {
throw 'oops';
} catch (e, s) {
expectedStack = s;
try {
throw 'oops again!';
} catch (e2, _) {}
await new Future.error(e, s);
}
yield 42;
}
try {
await foo().first;
fail('should not get here, an error should be thrown');
} catch (e, s) {
expect(e, 'oops');
expect(s, expectedStack);
}
});
}