Revert "Move dart2js from sdk/lib/_internal/compiler to pkg/compiler"

pkg/compiler/lib/src/ordered_typeset.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.
-
-library ordered_typeset;
-
-import 'dart2jslib.dart' show Compiler, MessageKind, invariant;
-import 'dart_types.dart';
-import 'elements/elements.dart' show ClassElement;
-import 'util/util.dart' show Link, LinkBuilder;
-import 'util/util_implementation.dart' show LinkEntry;
-
-/**
- * An ordered set of the supertypes of a class. The supertypes of a class are
- * ordered by decreasing hierarchy depth and by the order they are extended,
- * mixed in, or implemented.
- *
- * For these classes
- *
- *     class A {} // Depth = 1.
- *     class B {} // Depth = 1.
- *     class C extends B implements A {} // Depth 2.
- *
- * the ordered supertypes are
- *
- *     A: [A, Object]
- *     B: [B, Object]
- *     C: [C, B, A, Object]
- */
-class OrderedTypeSet {
-  final List<Link<DartType>> _levels;
-  final Link<DartType> types;
-  final Link<DartType> _supertypes;
-
-  OrderedTypeSet._internal(List<Link<DartType>> this._levels,
-                           Link<DartType> this.types,
-                           Link<DartType> this._supertypes);
-
-  factory OrderedTypeSet.singleton(DartType type) {
-    Link<DartType> types =
-        new LinkEntry<DartType>(type, const Link<DartType>());
-    List<Link<DartType>> list = new List<Link<DartType>>(1);
-    list[0] = types;
-    return new OrderedTypeSet._internal(list, types, const Link<DartType>());
-  }
-
-  /// Creates a new [OrderedTypeSet] for [type] when it directly extends the
-  /// class which this set represents. This is for instance used to create the
-  /// type set for [ClosureClassElement] which extends [Closure].
-  OrderedTypeSet extendClass(InterfaceType type) {
-    assert(invariant(type.element, types.head.treatAsRaw,
-        message: 'Cannot extend generic class ${types.head} using '
-                 'OrderedTypeSet.extendClass'));
-    Link<DartType> extendedTypes =
-        new LinkEntry<DartType>(type, types);
-    List<Link<DartType>> list = new List<Link<DartType>>(levels + 1);
-    for (int i = 0; i < levels; i++) {
-      list[i] = _levels[i];
-    }
-    list[levels] = extendedTypes;
-    return new OrderedTypeSet._internal(
-        list, extendedTypes, _supertypes.prepend(types.head));
-  }
-
-  Link<DartType> get supertypes => _supertypes;
-
-  int get levels => _levels.length;
-
-  int get maxDepth => levels - 1;
-
-  Link<DartType> operator [](int index) {
-    if (index < levels) {
-      return _levels[index];
-    }
-    return const Link<DartType>();
-  }
-
-  void forEach(int level, void f(DartType type)) {
-    if (level < levels) {
-      Link<DartType> pointer = _levels[level];
-      Link<DartType> end =
-          level > 0 ? _levels[level - 1] : const Link<DartType>();
-      while (!identical(pointer, end)) {
-        f(pointer.head);
-        pointer = pointer.tail;
-      }
-    }
-  }
-
-  InterfaceType asInstanceOf(ClassElement cls) {
-    int level = cls.hierarchyDepth;
-    if (level < levels) {
-      Link<DartType> pointer = _levels[level];
-      Link<DartType> end =
-          level > 0 ? _levels[level - 1] : const Link<DartType>();
-      while (!identical(pointer, end)) {
-        if (cls == pointer.head.element) {
-          return pointer.head;
-        }
-        pointer = pointer.tail;
-      }
-    }
-    return null;
-  }
-
-  String toString() => types.toString();
-}
-
-/**
- * Builder for creation an ordered set of the supertypes of a class. The
- * supertypes are ordered by decreasing hierarchy depth and by the order they
- * are extended, mixed in, or implemented.
- *
- * For these classes
- *
- *     class A {} // Depth = 1.
- *     class B {} // Depth = 1.
- *     class C extends B implements A {} // Depth 2.
- *
- * the ordered supertypes are
- *
- *     A: [A, Object]
- *     B: [B, Object]
- *     C: [C, B, A, Object]
- */
-class OrderedTypeSetBuilder {
-  Map<int, LinkEntry<DartType>> map = new Map<int, LinkEntry<DartType>>();
-  // TODO(15296): Avoid computing this order on the side when member
-  // lookup handles multiply inherited members correctly.
-  LinkBuilder<DartType> allSupertypes = new LinkBuilder<DartType>();
-  int maxDepth = -1;
-
-  final ClassElement cls;
-
-  OrderedTypeSetBuilder(this.cls);
-
-  void add(Compiler compiler, InterfaceType type) {
-    if (type.element == cls) {
-      if (type.element != compiler.objectClass) {
-        allSupertypes.addLast(compiler.objectClass.rawType);
-      }
-      _addAtDepth(compiler, type, maxDepth + 1);
-    } else {
-      if (type.element != compiler.objectClass) {
-        allSupertypes.addLast(type);
-      }
-      _addAtDepth(compiler, type, type.element.hierarchyDepth);
-    }
-  }
-
-  void _addAtDepth(Compiler compiler, InterfaceType type, int depth) {
-    LinkEntry<DartType> prev = null;
-    LinkEntry<DartType> link = map[depth];
-    while (link != null) {
-      DartType existingType = link.head;
-      if (existingType == type) return;
-      if (existingType.element == type.element) {
-        compiler.reportError(cls,
-            MessageKind.MULTI_INHERITANCE,
-            {'thisType': cls.thisType,
-             'firstType': existingType,
-             'secondType': type});
-        return;
-      }
-      prev = link;
-      link = link.tail;
-    }
-    LinkEntry<DartType> next = new LinkEntry<DartType>(type);
-    next.tail = null;
-    if (prev == null) {
-      map[depth] = next;
-    } else {
-      prev.tail = next;
-    }
-    if (depth > maxDepth) {
-      maxDepth = depth;
-    }
-  }
-
-  OrderedTypeSet toTypeSet() {
-    List<Link<DartType>> levels = new List<Link<DartType>>(maxDepth + 1);
-    if (maxDepth < 0) {
-      return new OrderedTypeSet._internal(
-          levels, const Link<DartType>(), const Link<DartType>());
-    }
-    Link<DartType> next = const Link<DartType>();
-    for (int depth = 0; depth <= maxDepth; depth++) {
-      LinkEntry<DartType> first = map[depth];
-      if (first == null) {
-        levels[depth] = next;
-      } else {
-        levels[depth] = first;
-        LinkEntry<DartType> last = first;
-        while (last.tail != null) {
-          last = last.tail;
-        }
-        last.tail = next;
-        next = first;
-      }
-    }
-    return new OrderedTypeSet._internal(
-        levels, levels.last, allSupertypes.toLink());
-  }
-
-  String toString() {
-    StringBuffer sb = new StringBuffer();
-    for (int depth = 0; depth <= maxDepth; depth++) {
-      sb.write('$depth: ');
-      LinkEntry<DartType> first = map[depth];
-      if (first != null) {
-        sb.write('${first.head}');
-        while (first.tail != null) {
-          sb.write(', ${first.tail.head}');
-          first = first.tail;
-        }
-      }
-      sb.write('\n');
-    }
-    return sb.toString();
-  }
-}