dart:io | Add Link class, as sibling to File and Directory.

tests/standalone/io/file_system_links_test.dart

Index: tests/standalone/io/file_system_links_test.dart
diff --git a/tests/standalone/io/file_system_links_test.dart b/tests/standalone/io/file_system_links_test.dart
index 25babf1282c445d298a84a61a99b81a7937fa3a4..9d2255d693204e19bd3c437be9b76f1bf0ef64a4 100644
--- a/tests/standalone/io/file_system_links_test.dart
+++ b/tests/standalone/io/file_system_links_test.dart
@@ -6,19 +6,8 @@ import "dart:io";
 import "dart:isolate";
 
 
-createLink(String dst, String link, bool symbolic, void callback()) {
-  var args = [ symbolic ? '-s' : '', dst, link ];
-  var script = 'tests/standalone/io/ln.sh';
-  if (!new File(script).existsSync()) {
-    script = '../$script';
-  }
-  Process.run(script, args).then((result) {
-    if (result.exitCode == 0) {
-      callback();
-    } else {
-      throw new Exception('link creation failed');
-    }
-  });
+createLink(String dst, String link, void callback()) {
+  new Link(link).create(dst, linkRelative: true).then((_) => callback());
 }
 
 
@@ -26,7 +15,7 @@ testFileExistsCreate() {
   var temp = new Directory('').createTempSync();
   var x = '${temp.path}${Platform.pathSeparator}x';
   var y = '${temp.path}${Platform.pathSeparator}y';
-  createLink(x, y, true, () {
+  createLink(x, y, () {
     Expect.isFalse(new File(y).existsSync());
     Expect.isFalse(new File(x).existsSync());
     Expect.isTrue(FileSystemEntity.isLinkSync(y));
@@ -79,13 +68,13 @@ testFileDelete() {
   var x = '${temp.path}${Platform.pathSeparator}x';
   var y = '${temp.path}${Platform.pathSeparator}y';
   new File(x).createSync();
-  createLink(x, y, true, () {
+  createLink(x, y, () {
     Expect.isTrue(new File(x).existsSync());
     Expect.isTrue(new File(y).existsSync());
     new File(y).deleteSync();
     Expect.isTrue(new File(x).existsSync());
     Expect.isFalse(new File(y).existsSync());
-    createLink(x, y, false, () {
+    createLink(x, y, () {
       Expect.isTrue(new File(x).existsSync());
       Expect.isTrue(new File(y).existsSync());
       new File(y).deleteSync();
@@ -102,7 +91,7 @@ testFileWriteRead() {
   var x = '${temp.path}${Platform.pathSeparator}x';
   var y = '${temp.path}${Platform.pathSeparator}y';
   new File(x).createSync();
-  createLink(x, y, true, () {
+  createLink(x, y, () {
     var data = "asdf".codeUnits;
     var output = new File(y).openWrite(mode: FileMode.WRITE);
     output.writeBytes(data);
@@ -122,7 +111,7 @@ testDirectoryExistsCreate() {
   var temp = new Directory('').createTempSync();
   var x = '${temp.path}${Platform.pathSeparator}x';
   var y = '${temp.path}${Platform.pathSeparator}y';
-  createLink(x, y, true, () {
+  createLink(x, y, () {
     Expect.isFalse(new Directory(x).existsSync());
     Expect.isFalse(new Directory(y).existsSync());
     Expect.throws(new Directory(y).createSync);
@@ -137,14 +126,14 @@ testDirectoryDelete() {
   var y = '${temp.path}${Platform.pathSeparator}y';
   var x = '${temp2.path}${Platform.pathSeparator}x';
   new File(x).createSync();
-  createLink(temp2.path, y, true, () {
+  createLink(temp2.path, y, () {
     var link = new Directory(y);
     Expect.isTrue(link.existsSync());
     Expect.isTrue(temp2.existsSync());
     link.deleteSync();
     Expect.isFalse(link.existsSync());
     Expect.isTrue(temp2.existsSync());
-    createLink(temp2.path, y, true, () {
+    createLink(temp2.path, y, () {
       Expect.isTrue(link.existsSync());
       temp.deleteSync(recursive: true);
       Expect.isFalse(link.existsSync());
@@ -163,7 +152,7 @@ testDirectoryListing() {
   var y = '${temp.path}${Platform.pathSeparator}y';
   var x = '${temp2.path}${Platform.pathSeparator}x';
   new File(x).createSync();
-  createLink(temp2.path, y, true, () {
+  createLink(temp2.path, y, () {
     var files = [];
     var dirs = [];
     for (var entry in temp.listSync(recursive:true)) {
@@ -210,7 +199,7 @@ testDirectoryListingBrokenLink() {
   var link = '${temp.path}${Platform.pathSeparator}link';
   var doesNotExist = 'this_thing_does_not_exist';
   new File(x).createSync();
-  createLink(doesNotExist, link, true, () {
+  createLink(doesNotExist, link, () {
     Expect.throws(() => temp.listSync(recursive: true),
                   (e) => e is DirectoryIOException);
     var files = [];