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

sdk/lib/io/link.dart

Index: sdk/lib/io/link.dart
diff --git a/sdk/lib/io/link.dart b/sdk/lib/io/link.dart
index d830e38951f85cb09da1997e8495db606dbe6d12..dfd08f7c463cbda890141a62359d037fab21894c 100644
--- a/sdk/lib/io/link.dart
+++ b/sdk/lib/io/link.dart
@@ -19,6 +19,11 @@ abstract class Link implements FileSystemEntity {
    * the link when it has been created. If the link exists,
    * the future will complete with an error.
    *
+   * If [recursive] is false, 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
@@ -29,12 +34,17 @@ abstract class Link implements FileSystemEntity {
    * 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 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
@@ -44,7 +54,7 @@ abstract class Link implements FileSystemEntity {
    * 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
@@ -145,21 +155,27 @@ class _Link extends FileSystemEntity implements Link {
 
   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 new Future.value(null)
+      .then((_) => recursive ? parent.exists() : true)

[Anders Johnsen, 2013/10/30 12:23:56]

Ditto.

[Bill Hesse, 2013/10/30 15:07:37]

Done.

+      .then((exists) => exists ? null : parent.create(recursive: true))
+      .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.existsSync()) {

[Anders Johnsen, 2013/10/30 12:23:56]

Ditto.

[Bill Hesse, 2013/10/30 15:07:37]

Done.

+      parent.createSync(recursive: true);
+    }
     if (Platform.operatingSystem == 'windows') {
       target = _makeWindowsLinkTarget(target);
     }