dart-sdk/tests/lib/async/stream_periodic3_test.dart
Robert Nystrom a2b556b937 Migrate lib_2/async to NNBD.
Change-Id: Ia5c41dda6503e1fbb8cc6099835d07588425e2ba
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/128310
Commit-Queue: Bob Nystrom <rnystrom@google.com>
Auto-Submit: Bob Nystrom <rnystrom@google.com>
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>
2020-01-09 22:04:37 +00:00

29 lines
1,002 B
Dart

// 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.
// Test merging streams.
library dart.test.stream_from_iterable;
import 'dart:async';
import 'package:async_helper/async_minitest.dart';
// The stopwatch is more precise than the Timer.
// Some browsers (Firefox and IE so far) can trigger too early. So we add more
// margin. We use identical(1, 1.0) as an easy way to know if the test is
// compiled by dart2js.
int get safetyMargin => identical(1, 1.0) ? 5 : 0;
main() {
test("stream-periodic3", () {
Stopwatch watch = new Stopwatch()..start();
Stream stream =
new Stream.periodic(const Duration(milliseconds: 1), (x) => x);
stream.take(10).listen((_) {}, onDone: expectAsync(() {
int millis = watch.elapsedMilliseconds + safetyMargin;
expect(millis, greaterThanOrEqualTo(10));
}));
});
}