Don't traverse through junctions when recursively deleting on Windows.

tests/standalone/io/directory_test.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.
 //
 // Directory listing test.
 
 #import("dart:io");
 #import("dart:isolate");
 
 class DirectoryTest {
@@ skipping 168 matching lines @@
     buffer.add(subDir.path);
     for (var i = 0; i < 1000; i++) {
       buffer.add("/../${subDirName}");
     }
     var long = new Directory("${buffer.toString()}");
     Expect.throws(long.deleteSync);
     Expect.throws(() => long.deleteRecursivelySync());
     d.deleteRecursivelySync();
   }
 
+  static void testDeleteSymlink() {
+    // temp/
+    //   a/
+    //     file.txt
+    //   b/
+    //     a_link -> a
+    var d = new Directory("").createTempSync();
+    var a = new Directory("${d.path}/a");
+    a.createSync();
+
+    var b = new Directory("${d.path}/b");
+    b.createSync();
+
+    var f = new File("${d.path}/a/file.txt");
+    f.createSync();
+    Expect.isTrue(f.existsSync());
+
+    // Create a symlink (or junction on Windows) from
+    // temp/b/a_link to temp/a.
+    var cmd = "ln";
+    var args = ['-s', "${d.path}/b/a_link", "${d.path}/a"];
+
+    if (Platform.operatingSystem == "windows") {
+      cmd = "cmd";
+      args = ["/c", "mklink", "/j", "${d.path}\\b\\a_link", "${d.path}\\a"];
+    }
+
+    Process.run(cmd, args).then((_) {
+      // Delete the directory containing the junction.
+      b.deleteRecursivelySync();
+
+      // We should not have recursed through a_link into a.
+      Expect.isTrue(f.existsSync());
+
+      // Clean up after ourselves.
+      d.deleteRecursivelySync();
+    });
+  }
+
   static void testExistsCreateDelete() {
     new Directory("").createTemp().then((d) {
       d.exists().then((bool exists) {
         Expect.isTrue(exists);
         Directory created = new Directory("${d.path}/subdir");
         created.create().then((ignore) {
           created.exists().then((bool exists) {
             Expect.isTrue(exists);
             created.delete().then((ignore) {
               created.exists().then((bool exists) {
@@ skipping 131 matching lines @@
   }
 
   static void testMain() {
     testListing();
     testListNonExistent();
     testListTooLongName();
     testDeleteNonExistent();
     testDeleteTooLongName();
     testDeleteNonExistentSync();
     testDeleteTooLongNameSync();
+    testDeleteSymlink();
     testExistsCreateDelete();
     testExistsCreateDeleteSync();
     testCreateTemp();
     testCreateDeleteTemp();
     testCurrent();
     testFromPath();
   }
 }
 
 
@@ skipping 79 matching lines @@
   temp2.rename(temp1.path).then((temp4) {
     Expect.isFalse(temp3.existsSync());
     Expect.isFalse(temp2.existsSync());
     Expect.isTrue(temp1.existsSync());
     Expect.isTrue(temp4.existsSync());
     Expect.equals(temp1.path, temp4.path);
     temp1.deleteRecursivelySync();
   });
 }
 
-
 main() {
   DirectoryTest.testMain();
   NestedTempDirectoryTest.testMain();
   testCreateTempErrorSync();
   testCreateTempError();
   testRename();
 }