Modify tests to use Directory.systemTemp

tests/standalone/io/directory_error_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.
 //
 // Dart test program for testing error handling in directory I/O.
 
 import "dart:async";
 import "dart:io";
 
 import "package:async_helper/async_helper.dart";
 import "package:expect/expect.dart";
 
 Directory tempDir() {
-  return new Directory('').createTempSync();
+  return Directory.systemTemp.createTempSync('dart_directory_error');
 }
 
 
 bool checkCreateInNonExistentFileException(e) {
   Expect.isTrue(e is DirectoryException);
   Expect.isTrue(e.osError != null);
   Expect.isTrue(e.toString().indexOf("Creation failed") != -1);
   if (Platform.operatingSystem == "linux") {
     Expect.equals(2, e.osError.errorCode);
   } else if (Platform.operatingSystem == "macos") {
@@ skipping 28 matching lines @@
   } else if (Platform.operatingSystem == "windows") {
     Expect.equals(3, e.osError.errorCode);
   }
 
   return true;
 }
 
 
 void testCreateTempInNonExistent(Directory temp, Function done) {
   Directory nonExistent = new Directory("${temp.path}/nonExistent/xxx");
-  Expect.throws(() => nonExistent.createTempSync(),
+  Expect.throws(() => nonExistent.createTempSync('tempdir'),
                 (e) => checkCreateTempInNonExistentFileException(e));
 
-  nonExistent.createTemp().catchError((error) {
+  nonExistent.createTemp('tempdir').catchError((error) {
     checkCreateTempInNonExistentFileException(error);
     done();
   });
 }
 
 
 bool checkDeleteNonExistentFileException(e) {
   Expect.isTrue(e is DirectoryException);
   Expect.isTrue(e.osError != null);
   // File not not found has error code 2 on all supported platforms.
@@ skipping 95 matching lines @@
   var renameDone = d.rename(newPath);
   renameDone.then((ignore) => Expect.fail('rename file as directory'))
             .catchError((error) {
               Expect.isTrue(error is DirectoryException);
               done();
             });
 }
 
 
 testRenameOverwriteFile(Directory temp, Function done) {
-  var d = new Directory('');
-  var temp1 = d.createTempSync();
+  var temp1 = Directory.systemTemp.createTempSync('dart_directory_error');
   var fileName = '${temp.path}/x';
   new File(fileName).createSync();
   Expect.throws(() => temp1.renameSync(fileName),
                 (e) => e is DirectoryException);
   var renameDone = temp1.rename(fileName);
   renameDone.then((ignore) => Expect.fail('rename dir overwrite file'))
             .catchError((error) {
               Expect.isTrue(error is DirectoryException);
               temp1.deleteSync(recursive: true);
               done();
             });
 }
 
 
 void runTest(Function test) {
   // Create a temporary directory for the test.
-  var temp = new Directory('').createTempSync();
+  var temp = Directory.systemTemp.createTempSync('dart_directory_error');
 
   // Wait for the test to finish and delete the temporary directory.
   asyncStart();
 
   // Run the test.
   test(temp, () {
     temp.deleteSync(recursive: true);
     asyncEnd();
   });
 }
 
 
 main() {
   runTest(testCreateInNonExistent);
   runTest(testCreateTempInNonExistent);
   runTest(testDeleteNonExistent);
   runTest(testDeleteRecursivelyNonExistent);
   runTest(testListNonExistent);
   runTest(testRenameNonExistent);
   runTest(testRenameFileAsDirectory);
   runTest(testRenameOverwriteFile);
 }