Resynthesize _DeferredClassElement lazily.

pkg/analyzer/lib/src/dart/element/handle.dart

 // Copyright (c) 2014, 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 analyzer.src.generated.element_handle;
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/constant/value.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
@@ skipping 80 matching lines @@
   @override
   InterfaceType get supertype => actualElement.supertype;
 
   @override
   InterfaceType get type => actualElement.type;
 
   @override
   List<TypeParameterElement> get typeParameters => actualElement.typeParameters;
 
   @override
-  ConstructorElement get unnamedConstructor => actualElement.unnamedConstructor;
+  ConstructorElement get unnamedConstructor {
+    ensureConstructorsReady();
+    return actualElement.unnamedConstructor;
+  }
 
   @override
   NamedCompilationUnitMember computeNode() => super.computeNode();
 
-  @override
-  FieldElement getField(String fieldName) => actualElement.getField(fieldName);
+  /**
+   * Ensure that [ClassElement.accessors] and [ClassElement.fields] are ready
+   * in [actualElement].
+   */
+  void ensureAccessorsReady() {}
+
+  /**
+   * The method is called by [ClassElementImpl.getImpl] before returning
+   * the [actualElement] as [ClassElementImpl]. At this moment we must ensure
+   * that [ClassElementImpl] is fully complete, we cannot continue filling it
+   * lazily.
+   */
+  void ensureActualElementComplete() {}
+
+  /**
+   * Ensure that [ClassElement.constructors] are ready in [actualElement].
+   */
+  void ensureConstructorsReady() {}
+
+  /**
+   * Ensure that [ClassElement.methods] are ready in [actualElement].
+   */
+  void ensureMethodsReady() {}
 
   @override
-  PropertyAccessorElement getGetter(String getterName) =>
-      actualElement.getGetter(getterName);
+  FieldElement getField(String fieldName) {
+    ensureAccessorsReady();
+    return actualElement.getField(fieldName);
+  }
 
   @override
-  MethodElement getMethod(String methodName) =>
-      actualElement.getMethod(methodName);
+  PropertyAccessorElement getGetter(String getterName) {
+    ensureAccessorsReady();
+    return actualElement.getGetter(getterName);
+  }
 
   @override
-  ConstructorElement getNamedConstructor(String name) =>
-      actualElement.getNamedConstructor(name);
+  MethodElement getMethod(String methodName) {
+    ensureMethodsReady();
+    return actualElement.getMethod(methodName);
+  }
 
   @override
-  PropertyAccessorElement getSetter(String setterName) =>
-      actualElement.getSetter(setterName);
+  ConstructorElement getNamedConstructor(String name) {
+    ensureConstructorsReady();
+    return actualElement.getNamedConstructor(name);
+  }
+
+  @override
+  PropertyAccessorElement getSetter(String setterName) {
+    ensureAccessorsReady();
+    return actualElement.getSetter(setterName);
+  }
 
   @override
   bool isSuperConstructorAccessible(ConstructorElement constructor) =>
       actualElement.isSuperConstructorAccessible(constructor);
 
   @override
   MethodElement lookUpConcreteMethod(
-          String methodName, LibraryElement library) =>
-      actualElement.lookUpConcreteMethod(methodName, library);
+      String methodName, LibraryElement library) {
+    ensureMethodsReady();
+    return actualElement.lookUpConcreteMethod(methodName, library);
+  }
 
   @override
   PropertyAccessorElement lookUpGetter(
           String getterName, LibraryElement library) =>
       actualElement.lookUpGetter(getterName, library);
 
   @override
   PropertyAccessorElement lookUpInheritedConcreteGetter(
-          String methodName, LibraryElement library) =>
-      actualElement.lookUpInheritedConcreteGetter(methodName, library);
+      String methodName, LibraryElement library) {
+    ensureAccessorsReady();
+    return actualElement.lookUpInheritedConcreteGetter(methodName, library);
+  }
 
   @override
   MethodElement lookUpInheritedConcreteMethod(
-          String methodName, LibraryElement library) =>
-      actualElement.lookUpInheritedConcreteMethod(methodName, library);
+      String methodName, LibraryElement library) {
+    ensureMethodsReady();
+    return actualElement.lookUpInheritedConcreteMethod(methodName, library);
+  }
 
   @override
   PropertyAccessorElement lookUpInheritedConcreteSetter(
-          String methodName, LibraryElement library) =>
-      actualElement.lookUpInheritedConcreteSetter(methodName, library);
+      String methodName, LibraryElement library) {
+    ensureAccessorsReady();
+    return actualElement.lookUpInheritedConcreteSetter(methodName, library);
+  }
 
   @override
   MethodElement lookUpInheritedMethod(
-          String methodName, LibraryElement library) =>
-      actualElement.lookUpInheritedMethod(methodName, library);
+      String methodName, LibraryElement library) {
+    ensureMethodsReady();
+    return actualElement.lookUpInheritedMethod(methodName, library);
+  }
 
   @override
-  MethodElement lookUpMethod(String methodName, LibraryElement library) =>
-      actualElement.lookUpMethod(methodName, library);
+  MethodElement lookUpMethod(String methodName, LibraryElement library) {
+    ensureMethodsReady();
+    return actualElement.lookUpMethod(methodName, library);
+  }
 
   @override
   PropertyAccessorElement lookUpSetter(
-          String setterName, LibraryElement library) =>
-      actualElement.lookUpSetter(setterName, library);
+      String setterName, LibraryElement library) {
+    ensureAccessorsReady();
+    return actualElement.lookUpSetter(setterName, library);
+  }
 }
 
 /**
  * A handle to a [CompilationUnitElement].
  */
 class CompilationUnitElementHandle extends ElementHandle
     implements CompilationUnitElement {
   /**
    * Initialize a newly created element handle to represent the element at the
    * given [_location]. The [_resynthesizer] will be used to resynthesize the
@@ skipping 231 matching lines @@
   @override
   accept(ElementVisitor visitor) => actualElement.accept(visitor);
 
   @override
   String computeDocumentationComment() => documentationComment;
 
   @override
   AstNode computeNode() => actualElement.computeNode();
 
   @override
-  Element getAncestor(Predicate<Element> predicate) =>
-      actualElement.getAncestor(predicate);
+  Element getAncestor(Predicate<Element> predicate) {
+    if (actualElement == null) {
+      print('No actualElement: $location  $runtimeType');

[Paul Berry, 2016/05/11 22:09:37]

Looks like temporary debugging code that should be removed.

+    }
+    return actualElement.getAncestor(predicate);
+  }
 
   @override
   String getExtendedDisplayName(String shortName) =>
       actualElement.getExtendedDisplayName(shortName);
 
   @override
   bool isAccessibleIn(LibraryElement library) =>
       actualElement.isAccessibleIn(library);
 
   @override
@@ skipping 675 matching lines @@
   @override
   bool get isPotentiallyMutatedInScope =>
       actualElement.isPotentiallyMutatedInScope;
 
   @override
   bool get isStatic => actualElement.isStatic;
 
   @override
   DartType get type => actualElement.type;
 }