Combine unmodifiable_collection package into collection_helpers.

pkg/unmodifiable_collection/lib/unmodifiable_collection.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.
-
-/**
- * Wrappers that prevent List, Set, or Map objects from being modified.
- *
- * The [Set] and [Map] wrappers allow reading from the wrapped collection,
- * but prohibit writing.
- *
- * The [List] wrapper prevents changes to the length of the wrapped list,
- * but allows changes to the contents.
- */
-library unmodifiable_collection;
-
-import "dart:math" show Random;
-export "dart:collection" show UnmodifiableListView;
-
-/**
- * A fixed-length list.
- *
- * A NonGrowableListView contains a [List] object and ensures that
- * its length does not change.
- * Methods that would change the length of the list,
- * such as [add] and [remove], throw an [UnsupportedError].
- *
- * This class _does_ allow changes to the contents of the wrapped list.
- * You can, for example, [sort] the list.
- * Permitted operations defer to the wrapped list.
- */
-class NonGrowableListView<E> extends _IterableView<E>
-                                     implements List<E> {
-  List<E> _source;
-  NonGrowableListView(List<E> source) : _source = source;
-
-  static void _throw() {
-    throw new UnsupportedError(
-        "Cannot change the length of a fixed-length list");
-  }
-
-  int get length => _source.length;
-
-  E operator [](int index) => _source[index];
-
-  int indexOf(E element, [int start = 0]) => _source.indexOf(element, start);
-
-  int lastIndexOf(E element, [int start])
-      => _source.lastIndexOf(element, start);
-
-  Iterable<E> getRange(int start, int end) => _source.getRange(start, end);
-
-  List<E> sublist(int start, [int end]) => _source.sublist(start, end);
-
-  Iterable<E> get reversed => _source.reversed;
-
-  Map<int, E> asMap() => _source.asMap();
-
-  void operator []=(int index, E value) { _source[index] = value; }
-
-  void sort([int compare(E a, E b)]) { _source.sort(compare); }
-
-  void shuffle([Random random]) { _source.shuffle(random); }
-
-  void setRange(int start, int end, Iterable<E> iterable, [int skipCount = 0]) {
-    _source.setRange(start, end, iterable, skipCount);
-  }
-
-  void fillRange(int start, int end, [E fillValue]) {
-    _source.fillRange(start, end, fillValue);
-  }
-
-  void setAll(int index, Iterable<E> iterable) {
-    _source.setAll(index, iterable);
-  }
-
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void set length(int newLength) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  bool add(E value) {
-    _throw();
-  }
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void addAll(Iterable<E> iterable) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void insert(int index, E element) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void insertAll(int index, Iterable<E> iterable) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  bool remove(Object value) { _throw(); }
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  E removeAt(int index) { _throw(); }
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  E removeLast() { _throw(); }
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void removeWhere(bool test(E element)) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void retainWhere(bool test(E element)) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void removeRange(int start, int end) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void replaceRange(int start, int end, Iterable<E> iterable) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the length of the list are disallowed.
-   */
-  void clear() => _throw();
-}
-
-/**
- * An unmodifiable set.
- *
- * An UnmodifiableSetView contains a [Set] object and ensures
- * that it does not change.
- * Methods that would change the set,
- * such as [add] and [remove], throw an [UnsupportedError].
- * Permitted operations defer to the wrapped set.
- */
-class UnmodifiableSetView<E> extends _IterableView<E>
-                                      implements Set<E> {
-  Set<E> _source;
-  UnmodifiableSetView(Set<E> source) : _source = source;
-
-  void _throw() {
-    throw new UnsupportedError("Cannot modify an unmodifiable Set");
-  }
-
-  bool containsAll(Iterable<E> other) => _source.containsAll(other);
-
-  Set<E> intersection(Set<E> other) => _source.intersection(other);
-
-  Set<E> union(Set<E> other) => _source.union(other);
-
-  Set<E> difference(Set<E> other) => _source.difference(other);
-
-  E lookup(Object object) => _source.lookup(object);
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the set are disallowed.
-   */
-  bool add(E value) {
-    _throw();
-  }
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the set are disallowed.
-   */
-  void addAll(Iterable<E> elements) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the set are disallowed.
-   */
-  bool remove(Object value) { _throw(); }
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the set are disallowed.
-   */
-  void removeAll(Iterable elements) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the set are disallowed.
-   */
-  void retainAll(Iterable elements) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the set are disallowed.
-   */
-  void removeWhere(bool test(E element)) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the set are disallowed.
-   */
-  void retainWhere(bool test(E element)) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the set are disallowed.
-   */
-  void clear() => _throw();
-}
-
-/**
- * An unmodifiable map.
- *
- * An UnmodifiableMapView contains a [Map] object and ensures
- * that it does not change.
- * Methods that would change the map,
- * such as [addAll] and [remove], throw an [UnsupportedError].
- * Permitted operations defer to the wrapped map.
- */
-class UnmodifiableMapView<K, V> implements Map<K, V> {
-  Map<K, V> _source;
-  UnmodifiableMapView(Map<K, V> source) : _source = source;
-
-  static void _throw() {
-    throw new UnsupportedError("Cannot modify an unmodifiable Map");
-  }
-
-  int get length => _source.length;
-
-  bool get isEmpty => _source.isEmpty;
-
-  bool get isNotEmpty => _source.isNotEmpty;
-
-  V operator [](K key) => _source[key];
-
-  bool containsKey(K key) => _source.containsKey(key);
-
-  bool containsValue(V value) => _source.containsValue(value);
-
-  void forEach(void f(K key, V value)) => _source.forEach(f);
-
-  Iterable<K> get keys => _source.keys;
-
-  Iterable<V> get values => _source.values;
-
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the map are disallowed.
-   */
-  void operator []=(K key, V value) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the map are disallowed.
-   */
-  V putIfAbsent(K key, V ifAbsent()) { _throw(); }
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the map are disallowed.
-   */
-  void addAll(Map<K, V> other) => _throw();
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the map are disallowed.
-   */
-  V remove(K key) { _throw(); }
-
-  /**
-   * Throws an [UnsupportedError];
-   * operations that change the map are disallowed.
-   */
-  void clear() => _throw();
-}
-
-abstract class _IterableView<E> {
-  Iterable<E> get _source;
-
-  bool any(bool test(E element)) => _source.any(test);
-
-  bool contains(E element) => _source.contains(element);
-
-  E elementAt(int index) => _source.elementAt(index);
-
-  bool every(bool test(E element)) => _source.every(test);
-
-  Iterable expand(Iterable f(E element)) => _source.expand(f);
-
-  E get first => _source.first;
-
-  E firstWhere(bool test(E element), { E orElse() })
-      => _source.firstWhere(test, orElse: orElse);
-
-  dynamic fold(var initialValue,
-               dynamic combine(var previousValue, E element))
-      => _source.fold(initialValue, combine);
-
-  void forEach(void f(E element)) => _source.forEach(f);
-
-  bool get isEmpty => _source.isEmpty;
-
-  bool get isNotEmpty => _source.isNotEmpty;
-
-  Iterator<E> get iterator => _source.iterator;
-
-  String join([String separator = ""]) => _source.join(separator);
-
-  E get last => _source.last;
-
-  E lastWhere(bool test(E element), {E orElse()})
-      => _source.lastWhere(test, orElse: orElse);
-
-  int get length => _source.length;
-
-  Iterable map(f(E element)) => _source.map(f);
-
-  E reduce(E combine(E value, E element)) => _source.reduce(combine);
-
-  E get single => _source.single;
-
-  E singleWhere(bool test(E element)) => _source.singleWhere(test);
-
-  Iterable<E> skip(int n) => _source.skip(n);
-
-  Iterable<E> skipWhile(bool test(E value)) => _source.skipWhile(test);
-
-  Iterable<E> take(int n) => _source.take(n);
-
-  Iterable<E> takeWhile(bool test(E value)) => _source.takeWhile(test);
-
-  List<E> toList({ bool growable: true }) => _source.toList(growable: growable);
-
-  Set<E> toSet() => _source.toSet();
-
-  Iterable<E> where(bool test(E element)) => _source.where(test);
-}