LibTest/collection/IterableMixin/firstWhere_A01_t01.dart

// Copyright (c) 2017, 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 E firstWhere(bool test(E value), { E orElse() })
/// Returns the first element that satisfies the given predicate [test].
/// @description Checks that the first element which satisfies [test] is
/// returned.
/// @author iarkh@unipro.ru

import "../../../Utils/expect.dart";
import "dart:collection";

class MyIterable extends Object with IterableMixin {
  List _content;
  MyIterable(List list): _content = list;

  Iterator get iterator {
    return _content.iterator;
  }
}

check(List list, bool test(value), int expected) {
  MyIterable iterable = new MyIterable(list);
  int actual = iterable.firstWhere(test);
  Expect.equals(expected, actual);
}

main() {
  check([1, 2, -3, 4, 128], (value) => value > 1, 2);
  check([1, 2, 128, 33, -5, 14, 0, -12, 126, -6], (value) => value < 0, -5);
}