LibTest/isolate/ReceivePort/skipWhile_A01_t01.dart

// Copyright (c) 2011, 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 Stream<T> skipWhile(bool test(T element))
/// Skip data events from this stream while they are matched by test.
/// Error and done events are provided by the returned stream unmodified.
/// Starting with the first data event where test returns true for the event data,
/// the returned stream will have the same events as this stream.
/// @description Checks that elements matched by a test are skipped.
/// @author kaigorodov

import "dart:async";
import "../../../Utils/expect.dart";
import "IsolateStream.dart" as IsolateStream;

/** index - first position in the stream where test() returns false
 */
void check(List data, bool test(var element), int index) {
  Stream s = IsolateStream.fromIterable(data);
  Stream t = s.skipWhile(test);
  bool seen = false;
  asyncStart();
  t.listen((value) {
    if (!seen) {
      Expect.isFalse(test(value), "test($value)=true");
      seen = true;
    } else {
      index++;
    }
    Expect.equals(data[index], value);
  }, onDone: () {
    Expect.equals(seen, index < data.length);
    asyncEnd();
  });
}

main() {
  check([], (element) => false , 0);
  check([1, 2, 3], (element) => false, 0);
  check([-1, -2, -3, 1, 2, 3], (element) => element < 0, 3);
  check([1, 2, 3], (element) => element == 1, 1);
  check([1, 2, 3], (element) => true, 3);
}