// 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.

// @dart = 2.9

/// @assertion Iterable map(f(E element))
/// The transformed elements will not be cached. Iterating multiple times over
/// the returned [Iterable] will invoke the supplied function [f] multiple times
/// on the same element.
/// @description Checks that iterating multiple times over the returned
/// [Iterable] will invoke the supplied function [f] multiple times on the same
/// element.
/// @author kaigorodov

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

List<int> visited = new List<int>(200);

int f(MyLinkedListEntry<int> entry) {
  int element = entry.value;
  visited[element]++;
  return element;
}
  
void checkResult(List<int> a, int expected) {
  LinkedList<MyLinkedListEntry<int>> llist = toLinkedList(a);
  int count = 0;
  Iterable<int> mapIter = llist.map(f);
  for (int el in mapIter) {
    count++;
  }
  Expect.equals(a.length, count);
  for (int k = 0; k < 200; k++) {
    Expect.equals(expected, visited[k]);
  }
}

main() {
  List<int> a=new List<int>();
  for (int k = 0; k < 200; k++) {
    a.add(k);
    visited[k] = 0;
  }
  checkResult(a, 1);
  checkResult(a, 2);
  checkResult(a, 3);
}