'Rename Local Variable' refactoring implementation.

pkg/analysis_services/lib/refactoring/refactoring.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 services.refactoring;
 
+import 'dart:async';
+
 import 'package:analysis_services/correction/change.dart';
 import 'package:analysis_services/correction/status.dart';
 import 'package:analysis_services/search/search_engine.dart';
 import 'package:analysis_services/src/refactoring/rename_local.dart';
 import 'package:analyzer/src/generated/element.dart';
 
 
 /**
  * Abstract interface for all refactorings.
  */
 abstract class Refactoring {
   /**
    * Returns the human readable name of this [Refactoring].
    */
   String get refactoringName;
 
   /**
    * Checks all conditions - [checkInitialConditions] and
    * [checkFinalConditions] to decide if refactoring can be performed.
    */
-  RefactoringStatus checkAllConditions();
+  Future<RefactoringStatus> checkAllConditions();

[Brian Wilkerson, 2014/08/12 04:44:40]

Is it really necessary to make refactorings async? :-(

[scheglov, 2014/08/12 05:09:33]

Unfortunately yes.
SearchEngine is async, and it is highly contagious.

I'm looking forward to being able to use the new async syntax!

 
   /**
    * Validates environment to check if this refactoring can be performed.
    *
    * This check may be slow, because many refactorings use search engine.
    */
-  RefactoringStatus checkFinalConditions();
+  Future<RefactoringStatus> checkFinalConditions();
 
   /**
    * Validates arguments to check if this refactoring can be performed.
    *
    * This check should be quick because it is used often as arguments change.
    */
-  RefactoringStatus checkInitialConditions();
+  Future<RefactoringStatus> checkInitialConditions();
 
   /**
    * Returns the [Change] to apply to perform this refactoring.
    */
-  Change createChange();
+  Future<Change> createChange();
 
   /**
    * Returs `true` if the [Change] created by refactoring may be unsafe,
    * so we want user to review the [Change] to ensure that he understands it.
    */
   bool requiresPreview();
 }
 
 
 /**
@@ skipping 26 matching lines @@
    * Validates that the [newName] is a valid identifier and is appropriate for
    * the type of the [Element] being renamed.
    *
    * It does not perform all the checks (such as checking for conflicts with any
    * existing names in any of the scopes containing the current name), as many
    * of these checkes require search engine. Use [checkFinalConditions] for this
    * level of checking.
    */
   RefactoringStatus checkNewName();
 }