LibTest/collection/LinkedHashMap/LinkedHashMap_A04_t01.dart

/*
 * Copyright (c) 2016, 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 LinkedHashMap({bool equals(K key1, K key2), int hashCode(K key),
 * bool isValidKey(potentialKey)})
 * ...
 * If using methods like operator[], remove and containsKey together with a
 * custom equality and hashcode, an extra isValidKey function can be supplied.
 * This function is called before calling equals or hashCode with an argument
 * that may not be a K instance, and if the call returns false, the key is
 * assumed to not be in the set. The isValidKey function defaults to just
 * testing if the object is a K instance.
 * @description Checks that if methods operator[], remove and containsKey
 * together with a custom equality and hashcode are used and an extra isValidKey
 * function is supplied then this function is called before calling equals or
 * hashCode
 * @author sgrekhov@unipro.ru
 */
import "../../../Utils/expect.dart";
import "dart:collection";

bool checkDone = false;
bool isValidKeyCalled = false;

bool myEquals(int key1, int key2) {
  if (!checkDone) {
    Expect.isTrue(isValidKeyCalled);
    checkDone = true;
  }
  return key1 == key2;
}

int myHashCode(int key) {
  if (!checkDone) {
    Expect.isTrue(isValidKeyCalled);
    checkDone = true;
  }
  return key.hashCode;
}

bool isValidKey(var potentialKey) {
  isValidKeyCalled = true;
  return potentialKey is int;
}

reset() {
  checkDone = false;
  isValidKeyCalled = false;
}
skip() {
  isValidKeyCalled = true;
}

main() {
  LinkedHashMap map = new LinkedHashMap(equals: myEquals, hashCode: myHashCode,
      isValidKey: isValidKey);
  skip();
  map[1] = 11;
  reset();
  map[1];
  reset();
  map.remove(1);
  reset();
  map.containsKey(1);
  skip();
  map[1] = 2;
  reset();
  map.containsKey(1);
}