dart:io | Add 'recursive' flag to File.create and Link.create.

sdk/lib/io/link.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.
 
 part of dart.io;
 
 /**
  * [Link] objects are references to filesystem links.
  *
  */
 abstract class Link implements FileSystemEntity {
   /**
    * Creates a Link object.
    */
   factory Link(String path) => new _Link(path);
 
   /**
    * Creates a symbolic link. Returns a [:Future<Link>:] that completes with
    * the link when it has been created. If the link exists,
    * the future will complete with an error.
    *
+   * If [recursive] is false, the default, the link is created
+   * only if all directories in its path exist.
+   * If [recursive] is true, all non-existing path
+   * components are created. The directories in the path of [target] are
+   * not affected, unless they are also in [path].
+   *
    * On the Windows platform, this will only work with directories, and the
    * target directory must exist. The link will be created as a Junction.
    * Only absolute links will be created, and relative paths to the target
    * will be converted to absolute paths by joining them with the path of the
    * directory the link is contained in.
    *
    * On other platforms, the posix symlink() call is used to make a symbolic
    * link containing the string [target].  If [target] is a relative path,
    * it will be interpreted relative to the directory containing the link.
    */
-  Future<Link> create(String target);
+  Future<Link> create(String target, {bool recursive: false});
 
   /**
    * Synchronously create the link. Calling [createSync] on an existing link
    * will throw an exception.
    *
+   * If [recursive] is false, the default, the link is created only if all
+   * directories in its path exist. If [recursive] is true, all
+   * non-existing path components are created. The directories in
+   * the path of [target] are not affected, unless they are also in [path].
+   *
    * On the Windows platform, this will only work with directories, and the
    * target directory must exist. The link will be created as a Junction.
    * Only absolute links will be created, and relative paths to the target
    * will be converted to absolute paths.
    *
    * On other platforms, the posix symlink() call is used to make a symbolic
    * link containing the string [target].  If [target] is a relative path,
    * it will be interpreted relative to the directory containing the link.
    */
-  void createSync(String target);
+  void createSync(String target, {bool recursive: false});
 
   /**
    * Synchronously updates the link. Calling [updateSync] on a non-existing link
    * will throw an exception.
    *
    * On the Windows platform, this will only work with directories, and the
    * target directory must exist.
    */
   void updateSync(String target);
 
@@ skipping 80 matching lines @@
   Future<bool> exists() => FileSystemEntity.isLink(path);
 
   bool existsSync() => FileSystemEntity.isLinkSync(path);
 
   Link get absolute => new Link(_absolutePath);
 
   Future<FileStat> stat() => FileStat.stat(path);
 
   FileStat statSync() => FileStat.statSync(path);
 
-  Future<Link> create(String target) {
+  Future<Link> create(String target, {bool recursive: false}) {
     if (Platform.operatingSystem == 'windows') {
       target = _makeWindowsLinkTarget(target);
     }
-    return _IOService.dispatch(_FILE_CREATE_LINK, [path, target])
-        .then((response) {
-          if (_isErrorResponse(response)) {
-            throw _exceptionFromResponse(
-                response, "Cannot create link to target '$target'", path);
-          }
-          return this;
-        });
+    return (recursive ? parent.create(recursive: true)
+                      : new Future.value(null))
+      .then((_) => _IOService.dispatch(_FILE_CREATE_LINK, [path, target]))
+      .then((response) {
+        if (_isErrorResponse(response)) {
+          throw _exceptionFromResponse(
+              response, "Cannot create link to target '$target'", path);
+        }
+        return this;
+      });
   }
 
-  void createSync(String target) {
+  void createSync(String target, {bool recursive: false}) {
+    if (recursive) {
+      parent.createSync(recursive: true);
+    }
     if (Platform.operatingSystem == 'windows') {
       target = _makeWindowsLinkTarget(target);
     }
     var result = _File._createLink(path, target);
     throwIfError(result, "Cannot create link", path);
   }
 
   // Put target into the form "\??\C:\my\target\dir".
   String _makeWindowsLinkTarget(String target) {
     Uri base = new Uri.file('${Directory.current.path}\\');
@@ skipping 96 matching lines @@
         return new ArgumentError();
       case _OSERROR_RESPONSE:
         var err = new OSError(response[_OSERROR_RESPONSE_MESSAGE],
                               response[_OSERROR_RESPONSE_ERROR_CODE]);
         return new FileSystemException(message, path, err);
       default:
         return new Exception("Unknown error");
     }
   }
 }