Fix AST-based type inference of enum types.

pkg/analyzer/lib/src/summary/link.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.
 
 /**
  * This library is capable of producing linked summaries from unlinked
  * ones (or prelinked ones).  It functions by building a miniature
  * element model to represent the contents of the summaries, and then
  * scanning the element model to gather linked information and adding
  * it to the summary data structures.
@@ skipping 414 matching lines @@
   List<MethodElementForLink> _methods;
   List<InterfaceType> _mixins;
   List<InterfaceType> _interfaces;
   List<PropertyAccessorElementForLink> _accessors;
 
   ClassElementForLink_Class(
       CompilationUnitElementForLink enclosingElement, this._unlinkedClass)
       : super(enclosingElement);
 
   @override
-  List<PropertyAccessorElement> get accessors {
+  List<PropertyAccessorElementForLink> get accessors {
     if (_accessors == null) {
       _accessors = <PropertyAccessorElementForLink>[];
       Map<String, SyntheticVariableElementForLink> syntheticVariables =
           <String, SyntheticVariableElementForLink>{};
       for (UnlinkedExecutable unlinkedExecutable
           in _unlinkedClass.executables) {
         if (unlinkedExecutable.kind == UnlinkedExecutableKind.getter ||
             unlinkedExecutable.kind == UnlinkedExecutableKind.setter) {
           String name = unlinkedExecutable.name;
           if (unlinkedExecutable.kind == UnlinkedExecutableKind.setter) {
@@ skipping 211 matching lines @@
  * linking.
  */
 class ClassElementForLink_Enum extends ClassElementForLink {
   /**
    * The unlinked representation of the enum in the summary.
    */
   final UnlinkedEnum _unlinkedEnum;
 
   InterfaceType _type;
   List<FieldElementForLink_EnumField> _fields;
+  List<PropertyAccessorElementForLink> _accessors;
+  DartType _valuesType;
 
   ClassElementForLink_Enum(
       CompilationUnitElementForLink enclosingElement, this._unlinkedEnum)
       : super(enclosingElement);
 
   @override
-  List<PropertyAccessorElement> get accessors {
-    // TODO(paulberry): do we need to include synthetic accessors?
-    return const [];
+  List<PropertyAccessorElementForLink> get accessors {
+    if (_accessors == null) {
+      _accessors = <PropertyAccessorElementForLink>[];
+      for (FieldElementForLink_EnumField field in fields) {
+        _accessors.add(field.getter);
+      }
+    }
+    return _accessors;
   }
 
   @override
   List<ConstructorElementForLink> get constructors => const [];
 
   @override
   String get displayName => _unlinkedEnum.name;
 
   @override
   List<FieldElementForLink_EnumField> get fields {
@@ skipping 27 matching lines @@
 
   @override
   DartType get type => _type ??= new InterfaceTypeImpl(this);
 
   @override
   List<TypeParameterElement> get typeParameters => const [];
 
   @override
   ConstructorElementForLink get unnamedConstructor => null;
 
+  /**
+   * Get the type of the enum's static member `values`.
+   */
+  DartType get valuesType =>
+      _valuesType ??= library._linker.typeProvider.listType.instantiate([type]);
+
   @override
   DartType buildType(DartType getTypeArgument(int i),
           List<int> implicitFunctionTypeIndices) =>
       type;
 
   @override
   void link(CompilationUnitElementInBuildUnit compilationUnit) {}
 
   @override
   String toString() => '$enclosingElement.$name';
@@ skipping 1832 matching lines @@
  * Specialization of [FieldElementForLink] for enum fields.
  */
 class FieldElementForLink_EnumField extends FieldElementForLink
     implements FieldElement {
   /**
    * The unlinked representation of the field in the summary, or `null` if this
    * is an enum's `values` field.
    */
   final UnlinkedEnumValue unlinkedEnumValue;
 
+  PropertyAccessorElementForLink_EnumField _getter;
+
   @override
   final ClassElementForLink_Enum enclosingElement;
 
   FieldElementForLink_EnumField(this.unlinkedEnumValue, this.enclosingElement);
 
   @override
+  PropertyAccessorElementForLink_EnumField get getter =>
+      _getter ??= new PropertyAccessorElementForLink_EnumField(this);
+
+  @override
   bool get isStatic => true;
 
   @override
   bool get isSynthetic => false;
 
   @override
   String get name =>
       unlinkedEnumValue == null ? 'values' : unlinkedEnumValue.name;
 
   @override
+  DartType get type => unlinkedEnumValue == null
+      ? enclosingElement.valuesType
+      : enclosingElement.type;
+
+  @override
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 
   @override
   String toString() => '$enclosingElement.$name';
 }
 
 /**
  * Element representing a function-typed parameter resynthesied from a summary
  * during linking.
  */
@@ skipping 1067 matching lines @@
 /**
  * Element representing a getter or setter resynthesized from a summary during
  * linking.
  */
 abstract class PropertyAccessorElementForLink
     implements PropertyAccessorElementImpl, ReferenceableElementForLink {
   void link(CompilationUnitElementInBuildUnit compilationUnit);
 }
 
 /**
+ * Specialization of [PropertyAccessorElementForLink] for synthetic accessors
+ * implied by the synthetic fields of an enum declaration.
+ */
+class PropertyAccessorElementForLink_EnumField
+    implements PropertyAccessorElementForLink {
+  @override
+  final FieldElementForLink_EnumField variable;
+
+  FunctionTypeImpl _type;
+
+  PropertyAccessorElementForLink_EnumField(this.variable);
+
+  @override
+  ConstructorElementForLink get asConstructor => null;
+
+  @override
+  ConstVariableNode get asConstVariable => null;
+
+  @override
+  DartType get asStaticType => returnType;
+
+  @override
+  TypeInferenceNode get asTypeInferenceNode => null;
+
+  @override
+  Element get enclosingElement => variable.enclosingElement;
+
+  @override
+  bool get isGetter => true;
+
+  @override
+  bool get isSetter => false;
+
+  @override
+  bool get isStatic => variable.isStatic;
+
+  @override
+  bool get isSynthetic => true;
+
+  @override
+  ElementKind get kind => ElementKind.GETTER;
+
+  @override
+  LibraryElementForLink get library =>
+      variable.enclosingElement.enclosingElement.enclosingElement;
+
+  @override
+  String get name => variable.name;
+
+  @override
+  List<ParameterElement> get parameters => const [];
+
+  @override
+  DartType get returnType => variable.type;
+
+  @override
+  FunctionTypeImpl get type => _type ??= new FunctionTypeImpl(this);
+
+  @override
+  List<TypeParameterElement> get typeParameters => const [];
+
+  @override
+  DartType buildType(DartType getTypeArgument(int i),
+          List<int> implicitFunctionTypeIndices) =>
+      DynamicTypeImpl.instance;
+
+  @override
+  ReferenceableElementForLink getContainedName(String name) {
+    return new NonstaticMemberElementForLink(library, this, name);
+  }
+
+  @override
+  bool isAccessibleIn(LibraryElement library) =>
+      !Identifier.isPrivateName(name) || identical(this.library, library);
+
+  @override
+  void link(CompilationUnitElementInBuildUnit compilationUnit) {}
+
+  @override
+  noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
+
+  @override
+  String toString() => '$enclosingElement.$name';
+}
+
+/**
  * Specialization of [PropertyAccessorElementForLink] for non-synthetic
  * accessors explicitly declared in the source code.
  */
 class PropertyAccessorElementForLink_Executable extends ExecutableElementForLink
     implements PropertyAccessorElementForLink {
   @override
   SyntheticVariableElementForLink variable;
 
   PropertyAccessorElementForLink_Executable(
       CompilationUnitElementForLink enclosingUnit,
@@ skipping 932 matching lines @@
    * there are no type parameters in scope.
    */
   TypeParameterizedElementForLink get _typeParameterContext;
 
   @override
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 
   @override
   String toString() => '$enclosingElement.$name';
 }