Add support for directory renaming to dart:io.

runtime/bin/directory_impl.dart

 // Copyright (c) 2012, 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.
 
 
 class _Directory implements Directory {
   static final kCreateRequest = 0;
   static final kDeleteRequest = 1;
   static final kExistsRequest = 2;
   static final kCreateTempRequest = 3;
   static final kListRequest = 4;
+  static final kRenameRequest = 5;
 
   static final kSuccessResponse = 0;
   static final kIllegalArgumentResponse = 1;
   static final kOSErrorResponse = 2;
 
   _Directory(String this._path);
   _Directory.current() : _path = _current();
 
   static String _current() native "Directory_Current";
   static _createTemp(String template) native "Directory_CreateTemp";
   static int _exists(String path) native "Directory_Exists";
   static _create(String path) native "Directory_Create";
   static _delete(String path, bool recursive) native "Directory_Delete";
+  static _rename(String path, String newPath) native "Directory_Rename";
   static SendPort _newServicePort() native "Directory_NewServicePort";
 
   Future<bool> exists() {
     _ensureDirectoryService();
-    Completer<bool> completer = new Completer<bool>();
     List request = new List(2);
     request[0] = kExistsRequest;
     request[1] = _path;
-    _directoryService.call(request).then((response) {
+    return _directoryService.call(request).transform((response) {
       if (_isErrorResponse(response)) {
-        var e = _exceptionFromResponse(response, "Exists failed");
-        completer.completeException(e);
-      } else {
-        completer.complete(response == 1);
+        throw _exceptionFromResponse(response, "Exists failed");
       }
+      return response == 1;
     });
-    return completer.future;
   }
 
   bool existsSync() {
     if (_path is !String) {
       throw new IllegalArgumentException();
     }
     var result = _exists(_path);
     if (result is OSError) {
       throw new DirectoryIOException("Exists failed", _path, result);
     }
     return (result == 1);
   }
 
   Future<Directory> create() {
     _ensureDirectoryService();
-    Completer<Directory> completer = new Completer<Directory>();
     List request = new List(2);
     request[0] = kCreateRequest;
     request[1] = _path;
-    _directoryService.call(request).then((response) {
+    return _directoryService.call(request).transform((response) {
       if (_isErrorResponse(response)) {
-        var e = _exceptionFromResponse(response, "Creation failed");
-        completer.completeException(e);
-      } else {
-        completer.complete(this);
+        throw _exceptionFromResponse(response, "Creation failed");
       }
+      return this;
     });
-    return completer.future;
   }
 
   void createSync() {
     if (_path is !String) {
       throw new IllegalArgumentException();
     }
     var result = _create(_path);
     if (result is OSError) {
       throw new DirectoryIOException("Creation failed", _path, result);
     }
   }
 
   Future<Directory> createTemp() {
     _ensureDirectoryService();
-    Completer<Directory> completer = new Completer<Directory>();
     List request = new List(2);
     request[0] = kCreateTempRequest;
     request[1] = _path;
-    _directoryService.call(request).then((response) {
+    return _directoryService.call(request).transform((response) {
       if (_isErrorResponse(response)) {
-        var e =
-            _exceptionFromResponse(response,
-                                   "Creation of temporary directory failed");
-        completer.completeException(e);
-      } else {
-        completer.complete(new Directory(response));
+        throw _exceptionFromResponse(response,
+                                     "Creation of temporary directory failed");
       }
+      return new Directory(response);
     });
-    return completer.future;
   }
 
   void createTempSync() {
     if (_path is !String) {
       throw new IllegalArgumentException();
     }
     var result = _createTemp(path);
     if (result is OSError) {
       throw new DirectoryIOException("Creation of temporary directory failed",
                                      _path,
                                      result);
     }
     return new Directory(result);
   }
 
   Future<Directory> _deleteHelper(bool recursive, String errorMsg) {
     _ensureDirectoryService();
-    Completer<Directory> completer = new Completer<Directory>();
     List request = new List(3);
     request[0] = kDeleteRequest;
     request[1] = _path;
     request[2] = recursive;
-    _directoryService.call(request).then((response) {
+    return _directoryService.call(request).transform((response) {
       if (_isErrorResponse(response)) {
-        var e = _exceptionFromResponse(response, errorMsg);
-        completer.completeException(e);
-      } else {
-        completer.complete(this);
+        throw _exceptionFromResponse(response, errorMsg);
       }
+      return this;
     });
     return completer.future;
   }
 
   Future<Directory> delete() {
     return _deleteHelper(false, "Deletion failed");
   }
 
-  Future<Directory> deleteRecursively() {
-    return _deleteHelper(true, "Deletion failed");
-  }
-
   void deleteSync() {
     if (_path is !String) {
       throw new IllegalArgumentException();
     }
     var result = _delete(_path, false);
     if (result is OSError) {
       throw new DirectoryIOException("Deletion failed", _path, result);
     }
   }
 
+  Future<Directory> deleteRecursively() {
+    return _deleteHelper(true, "Deletion failed");
+  }
+
   void deleteRecursivelySync() {
     if (_path is !String) {
       throw new IllegalArgumentException();
     }
     var result = _delete(_path, true);
     if (result is OSError) {
       throw new DirectoryIOException("Deletion failed", _path, result);
     }
   }
 
+  Future<Directory> rename(String newPath) {
+    _ensureDirectoryService();
+    List request = new List(3);
+    request[0] = kRenameRequest;
+    request[1] = _path;
+    request[2] = newPath;
+    return _directoryService.call(request).transform((response) {
+      if (_isErrorResponse(response)) {
+        throw _exceptionFromResponse(response, "Rename failed");
+      }
+      return new Directory(newPath);
+    });
+  }
+
+  Directory renameSync(String newPath) {
+    if (_path is !String || newPath is !String) {
+      throw new IllegalArgumentException();
+    }
+    var result = _rename(_path, newPath);
+    if (result is OSError) {
+      throw new DirectoryIOException("Rename failed", _path, result);
+    }
+    return new Directory(newPath);
+  }
+
   DirectoryLister list([bool recursive = false]) {
     return new _DirectoryLister(_path, recursive);
   }
 
   String get path() { return _path; }
 
   bool _isErrorResponse(response) {
     return response is List && response[0] != _FileUtils.kSuccessResponse;
   }
 
@@ skipping 100 matching lines @@
     } else {
       throw e;
     }
   }
 
   Function _onDir;
   Function _onFile;
   Function _onDone;
   Function _onError;
 }