Revert "Convert HashSet, LinkedHashSet to factory methods and custom implementations."

sdk/lib/_internal/lib/collection_patch.dart

Index: sdk/lib/_internal/lib/collection_patch.dart
diff --git a/sdk/lib/_internal/lib/collection_patch.dart b/sdk/lib/_internal/lib/collection_patch.dart
index 3ae7dab778f86a796d70baea07aebe73c46f9bdc..670b4ab51d4c09cd4923f2fe11b5896ce182bfb0 100644
--- a/sdk/lib/_internal/lib/collection_patch.dart
+++ b/sdk/lib/_internal/lib/collection_patch.dart
@@ -883,30 +883,6 @@ class LinkedHashMapKeyIterator<E> implements Iterator<E> {
 }
 
 patch class HashSet<E> {
-  patch factory HashSet({ bool equals(E e1, E e2),
-                          int hashCode(E e),
-                          bool isValidKey(potentialKey) }) {
-    if (isValidKey == null) {
-      if (hashCode == null) {
-        if (equals == null) {
-          return new _HashSet<E>();
-        }
-        if (identical(identical, equals)) {
-          return new _IdentityHashSet<E>();
-        }
-        hashCode = _defaultHashCode;
-      } else if (equals == null) {
-        equals = _defaultEquals;
-      }
-    } else {
-      if (hashCode == null) hashCode = _defaultHashCode;
-      if (equals == null) equals = _defaultEquals;
-    }
-    return new _CustomHashSet<E>(equals, hashCode, isValidKey);
-  }
-}
-
-class _HashSet<E> extends _HashSetBase<E> implements HashSet<E> {
   int _length = 0;
 
   // The hash set contents are divided into three parts: one part for
@@ -928,20 +904,18 @@ class _HashSet<E> extends _HashSetBase<E> implements HashSet<E> {
   // guard against concurrent modifications.
   List _elements;
 
-  _HashSet();
-
-  Set<E> _newSet() => new _HashSet<E>();
+  patch HashSet();
 
   // Iterable.
-  Iterator<E> get iterator {
+  patch Iterator<E> get iterator {
     return new HashSetIterator<E>(this, _computeElements());
   }
 
-  int get length => _length;
-  bool get isEmpty => _length == 0;
-  bool get isNotEmpty => !isEmpty;
+  patch int get length => _length;
+  patch bool get isEmpty => _length == 0;
+  patch bool get isNotEmpty => !isEmpty;
 
-  bool contains(Object object) {
+  patch bool contains(Object object) {
     if (_isStringElement(object)) {
       var strings = _strings;
       return (strings == null) ? false : _hasTableEntry(strings, object);
@@ -957,7 +931,7 @@ class _HashSet<E> extends _HashSetBase<E> implements HashSet<E> {
   }
 
   // Collection.
-  void add(E element) {
+  patch void add(E element) {
     if (_isStringElement(element)) {
       var strings = _strings;
       if (strings == null) _strings = strings = _newHashTable();
@@ -983,13 +957,13 @@ class _HashSet<E> extends _HashSetBase<E> implements HashSet<E> {
     }
   }
 
-  void addAll(Iterable<E> objects) {
+  patch void addAll(Iterable<E> objects) {
     for (E each in objects) {
       add(each);
     }
   }
 
-  bool remove(Object object) {
+  patch bool remove(Object object) {
     if (_isStringElement(object)) {
       return _removeHashTableEntry(_strings, object);
     } else if (_isNumericElement(object)) {
@@ -1011,21 +985,21 @@ class _HashSet<E> extends _HashSetBase<E> implements HashSet<E> {
     }
   }
 
-  void removeAll(Iterable<Object> objectsToRemove) {
+  patch void removeAll(Iterable<Object> objectsToRemove) {
     for (var each in objectsToRemove) {
       remove(each);
     }
   }
 
-  void removeWhere(bool test(E element)) {
+  patch void removeWhere(bool test(E element)) {
     removeAll(_computeElements().where(test));
   }
 
-  void retainWhere(bool test(E element)) {
+  patch void retainWhere(bool test(E element)) {
     removeAll(_computeElements().where((E element) => !test(element)));
   }
 
-  void clear() {
+  patch void clear() {
     if (_length > 0) {
       _strings = _nums = _rest = _elements = null;
       _length = 0;
@@ -1112,7 +1086,7 @@ class _HashSet<E> extends _HashSetBase<E> implements HashSet<E> {
         JS('bool', '(# & 0x3ffffff) === #', element, element);
   }
 
-  int _computeHashCode(var element) {
+  static int _computeHashCode(var element) {
     // We force the hash codes to be unsigned 30-bit integers to avoid
     // issues with problematic elements like '__proto__'. Another
     // option would be to throw an exception if the hash code isn't a
@@ -1137,12 +1111,12 @@ class _HashSet<E> extends _HashSetBase<E> implements HashSet<E> {
     JS('void', 'delete #[#]', table, key);
   }
 
-  List _getBucket(var table, var element) {
+  static List _getBucket(var table, var element) {
     var hash = _computeHashCode(element);
     return JS('var', '#[#]', table, hash);
   }
 
-  int _findBucketIndex(var bucket, var element) {
+  static int _findBucketIndex(var bucket, var element) {
     if (bucket == null) return -1;
     int length = JS('int', '#.length', bucket);
     for (int i = 0; i < length; i++) {
@@ -1165,56 +1139,6 @@ class _HashSet<E> extends _HashSetBase<E> implements HashSet<E> {
   }
 }
 
-class _IdentityHashSet<E> extends _HashSet<E> {
-  Set<E> _newSet() => new _IdentityHashSet<E>();
-
-  int _findBucketIndex(var bucket, var element) {
-    if (bucket == null) return -1;
-    int length = JS('int', '#.length', bucket);
-    for (int i = 0; i < length; i++) {
-      if (identical(JS('var', '#[#]', bucket, i), element)) return i;
-    }
-    return -1;
-  }
-}
-
-class _CustomHashSet<E> extends _HashSet<E> {
-  _Equality<E> _equality;
-  _Hasher<E> _hasher;
-  _Predicate _validKey;
-  _CustomHashSet(this._equality, this._hasher, bool validKey(potentialKey))
-      : _validKey = (validKey != null) ? validKey : ((x) => x is E);
-
-  Set<E> _newSet() => new _CustomHashSet<E>(_equality, _hasher, _validKey);
-
-  int _findBucketIndex(var bucket, var element) {
-    if (bucket == null) return -1;
-    int length = JS('int', '#.length', bucket);
-    for (int i = 0; i < length; i++) {
-      if (_equality(JS('var', '#[#]', bucket, i), element)) return i;
-    }
-    return -1;
-  }
-
-  int _computeHashCode(var element) {
-    // We force the hash codes to be unsigned 30-bit integers to avoid
-    // issues with problematic elements like '__proto__'. Another
-    // option would be to throw an exception if the hash code isn't a
-    // number.
-    return JS('int', '# & 0x3ffffff', _hasher(element));
-  }
-
-  bool contains(Object object) {
-    if (!_validKey(object)) return false;
-    return super.contains(object);
-  }
-
-  bool remove(Object object) {
-    if (!_validKey(object)) return false;
-    return super.remove(object);
-  }
-}
-
 // TODO(kasperl): Share this code with HashMapKeyIterator<E>?
 class HashSetIterator<E> implements Iterator<E> {
   final _set;
@@ -1245,31 +1169,7 @@ class HashSetIterator<E> implements Iterator<E> {
   }
 }
 
-patch class LinkedHashSet<E> {
-  patch factory LinkedHashSet({ bool equals(E e1, E e2),
-                                int hashCode(E e),
-                                bool isValidKey(potentialKey) }) {
-    if (isValidKey == null) {
-      if (hashCode == null) {
-        if (equals == null) {
-          return new _LinkedHashSet<E>();
-        }
-        if (identical(identical, equals)) {
-          return new _LinkedIdentityHashSet<E>();
-        }
-        hashCode = _defaultHashCode;
-      } else if (equals == null) {
-        equals = _defaultEquals;
-      }
-    } else {
-      if (hashCode == null) hashCode = _defaultHashCode;
-      if (equals == null) equals = _defaultEquals;
-    }
-    return new _LinkedCustomHashSet<E>(equals, hashCode, isValidKey);
-  }
-}
-
-class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
+patch class LinkedHashSet<E> extends _HashSetBase<E> {
   int _length = 0;
 
   // The hash set contents are divided into three parts: one part for
@@ -1295,24 +1195,22 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
   // over.
   int _modifications = 0;
 
-  _LinkedHashSet();
-
-  Set<E> _newSet() => new _LinkedHashSet<E>();
+  patch LinkedHashSet();
 
   void _unsupported(String operation) {
     throw 'LinkedHashSet: unsupported $operation';
   }
 
   // Iterable.
-  Iterator<E> get iterator {
+  patch Iterator<E> get iterator {
     return new LinkedHashSetIterator(this, _modifications);
   }
 
-  int get length => _length;
-  bool get isEmpty => _length == 0;
-  bool get isNotEmpty => !isEmpty;
+  patch int get length => _length;
+  patch bool get isEmpty => _length == 0;
+  patch bool get isNotEmpty => !isEmpty;
 
-  bool contains(Object object) {
+  patch bool contains(Object object) {
     if (_isStringElement(object)) {
       var strings = _strings;
       if (strings == null) return false;
@@ -1331,7 +1229,7 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
     }
   }
 
-  void forEach(void action(E element)) {
+  patch void forEach(void action(E element)) {
     LinkedHashSetCell cell = _first;
     int modifications = _modifications;
     while (cell != null) {
@@ -1343,18 +1241,18 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
     }
   }
 
-  E get first {
+  patch E get first {
     if (_first == null) throw new StateError("No elements");
     return _first._element;
   }
 
-  E get last {
+  patch E get last {
     if (_last == null) throw new StateError("No elements");
     return _last._element;
   }
 
   // Collection.
-  void add(E element) {
+  patch void add(E element) {
     if (_isStringElement(element)) {
       var strings = _strings;
       if (strings == null) _strings = strings = _newHashTable();
@@ -1380,13 +1278,13 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
     }
   }
 
-  void addAll(Iterable<E> objects) {
+  patch void addAll(Iterable<E> objects) {
     for (E object in objects) {
       add(object);
     }
   }
 
-  bool remove(Object object) {
+  patch bool remove(Object object) {
     if (_isStringElement(object)) {
       return _removeHashTableEntry(_strings, object);
     } else if (_isNumericElement(object)) {
@@ -1405,17 +1303,17 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
     }
   }
 
-  void removeAll(Iterable objectsToRemove) {
+  patch void removeAll(Iterable objectsToRemove) {
     for (var each in objectsToRemove) {
       remove(each);
     }
   }
 
-  void removeWhere(bool test(E element)) {
+  patch void removeWhere(bool test(E element)) {
     _filterWhere(test, true);
   }
 
-  void retainWhere(bool test(E element)) {
+  patch void retainWhere(bool test(E element)) {
     _filterWhere(test, false);
   }
 
@@ -1434,7 +1332,7 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
     }
   }
 
-  void clear() {
+  patch void clear() {
     if (_length > 0) {
       _strings = _nums = _rest = _first = _last = null;
       _length = 0;
@@ -1511,7 +1409,7 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
         JS('bool', '(# & 0x3ffffff) === #', element, element);
   }
 
-  int _computeHashCode(var element) {
+  static int _computeHashCode(var element) {
     // We force the hash codes to be unsigned 30-bit integers to avoid
     // issues with problematic elements like '__proto__'. Another
     // option would be to throw an exception if the hash code isn't a
@@ -1532,12 +1430,12 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
     JS('void', 'delete #[#]', table, key);
   }
 
-  List _getBucket(var table, var element) {
+  static List _getBucket(var table, var element) {
     var hash = _computeHashCode(element);
     return JS('var', '#[#]', table, hash);
   }
 
-  int _findBucketIndex(var bucket, var element) {
+  static int _findBucketIndex(var bucket, var element) {
     if (bucket == null) return -1;
     int length = JS('int', '#.length', bucket);
     for (int i = 0; i < length; i++) {
@@ -1561,60 +1459,6 @@ class _LinkedHashSet<E> extends _HashSetBase<E> implements LinkedHashSet<E> {
   }
 }
 
-class _LinkedIdentityHashSet<E> extends _LinkedHashSet<E> {
-  Set<E> _newSet() => new _LinkedIdentityHashSet<E>();
-
-  int _findBucketIndex(var bucket, var element) {
-    if (bucket == null) return -1;
-    int length = JS('int', '#.length', bucket);
-    for (int i = 0; i < length; i++) {
-      LinkedHashSetCell cell = JS('var', '#[#]', bucket, i);
-      if (identical(cell._element, element)) return i;
-    }
-    return -1;
-  }
-}
-
-class _LinkedCustomHashSet<E> extends _LinkedHashSet<E> {
-  _Equality<E> _equality;
-  _Hasher<E> _hasher;
-  _Predicate _validKey;
-  _LinkedCustomHashSet(this._equality, this._hasher,
-                       bool validKey(potentialKey))
-      : _validKey = (validKey != null) ? validKey : ((x) => x is E);
-
-  Set<E> _newSet() =>
-      new _LinkedCustomHashSet<E>(_equality, _hasher, _validKey);
-
-  int _findBucketIndex(var bucket, var element) {
-    if (bucket == null) return -1;
-    int length = JS('int', '#.length', bucket);
-    for (int i = 0; i < length; i++) {
-      LinkedHashSetCell cell = JS('var', '#[#]', bucket, i);
-      if (_equality(cell._element, element)) return i;
-    }
-    return -1;
-  }
-
-  int _computeHashCode(var element) {
-    // We force the hash codes to be unsigned 30-bit integers to avoid
-    // issues with problematic elements like '__proto__'. Another
-    // option would be to throw an exception if the hash code isn't a
-    // number.
-    return JS('int', '# & 0x3ffffff', _hasher(element));
-  }
-
-  bool contains(Object object) {
-    if (!_validKey(object)) return false;
-    return super.contains(object);
-  }
-
-  bool remove(Object object) {
-    if (!_validKey(object)) return false;
-    return super.remove(object);
-  }
-}
-
 class LinkedHashSetCell {
   final _element;