Make createTempDir() synchronous.

utils/tests/pub/test_pub.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.
 
 /// Test infrastructure for testing pub. Unlike typical unit tests, most pub
 /// tests are integration tests that stage some stuff on the file system, run
 /// pub, and then validate the results. This library provides an API to build
 /// tests like that.
 library test_pub;
 
@@ skipping 476 matching lines @@
     dir(sdkPath, [
       file('version', '0.1.2.3')
     ]).scheduleCreate();
 
     // Schedule the test.
     body();
 
     // Run all of the scheduled tasks. If an error occurs, it will propagate
     // through the futures back up to here where we can hand it off to unittest.
     var asyncDone = expectAsync0(() {});
-    var createdSandboxDir;
-    _setUpSandbox().then((sandboxDir) {
-      createdSandboxDir = sandboxDir;
-      return timeout(_runScheduled(sandboxDir, _scheduled),
-          _TIMEOUT, 'waiting for a test to complete');
-    }).catchError((e) {
-      return _runScheduled(createdSandboxDir, _scheduledOnException).then((_) {
+    var sandboxDir = createTempDir();
+    return timeout(_runScheduled(sandboxDir, _scheduled),
+          _TIMEOUT, 'waiting for a test to complete').catchError((e) {
+      return _runScheduled(sandboxDir, _scheduledOnException).then((_) {
         // Rethrow the original error so it keeps propagating.
         throw e;
       });
     }).whenComplete(() {
       // Clean up after ourselves. Do this first before reporting back to
       // unittest because it will advance to the next test immediately.
-      return _runScheduled(createdSandboxDir, _scheduledCleanup).then((_) {
+      return _runScheduled(sandboxDir, _scheduledCleanup).then((_) {
         _scheduled = null;
         _scheduledCleanup = null;
         _scheduledOnException = null;
-        if (createdSandboxDir != null) return deleteDir(createdSandboxDir);
+        if (sandboxDir != null) return deleteDir(sandboxDir);
       });
     }).then((_) {
       // If we got here, the test completed successfully so tell unittest so.
       asyncDone();
     }).catchError((e) {
       // If we got here, an error occurred. We will register it with unittest
       // directly so that the error message isn't wrapped in any matcher stuff.
       // We do this call last because it will cause unittest to *synchronously*
       // advance to the next test and run it.
       registerException(e.error, e.stackTrace);
@@ skipping 148 matching lines @@
 /// Note that this will only affect HTTP requests made via http.dart in the
 /// parent process.
 void useMockClient(MockClient client) {
   var oldInnerClient = httpClient.inner;
   httpClient.inner = client;
   _scheduleCleanup((_) {
     httpClient.inner = oldInnerClient;
   });
 }
 
-Future<Directory> _setUpSandbox() => createTempDir();
-
 Future _runScheduled(Directory parentDir, List<_ScheduledEvent> scheduled) {
   if (scheduled == null) return new Future.immediate(null);
   var iterator = scheduled.iterator;
 
   Future runNextEvent(_) {
     if (_abortScheduled || !iterator.moveNext()) {
       _abortScheduled = false;
       scheduled.clear();
       return new Future.immediate(null);
     }
@@ skipping 402 matching lines @@
 /// Describes a gzipped tar file and its contents.
 class TarFileDescriptor extends Descriptor {
   final List<Descriptor> contents;
 
   TarFileDescriptor(Pattern name, this.contents)
   : super(name);
 
   /// Creates the files and directories within this tar file, then archives
   /// them, compresses them, and saves the result to [parentDir].
   Future<File> create(parentDir) {
-    // TODO(rnystrom): Use withTempDir().
-    var tempDir;
-    return createTempDir().then((_tempDir) {
-      tempDir = _tempDir;
-      return Future.wait(contents.map((child) => child.create(tempDir)));
-    }).then((createdContents) {
-      return createTarGz(createdContents, baseDir: tempDir).toBytes();
-    }).then((bytes) {
-      return new File(join(parentDir, _stringName)).writeAsBytes(bytes);
-    }).then((file) {
-      return deleteDir(tempDir).then((_) => file);
+    return withTempDir((tempDir) {
+      return Future.wait(contents.map((child) => child.create(tempDir)))
+          .then((createdContents) {
+        return createTarGz(createdContents, baseDir: tempDir).toBytes();
+      }).then((bytes) {
+        return new File(join(parentDir, _stringName)).writeAsBytes(bytes);
+      });
     });
   }
 
   /// Validates that the `.tar.gz` file at [path] contains the expected
   /// contents.
   Future validate(String path) {
     throw "TODO(nweiz): implement this";
   }
 
   Future delete(dir) {
     throw new UnsupportedError('');
   }
 
   /// Loads the contents of this tar file.
   ByteStream load(List<String> path) {
     if (!path.isEmpty) {
       var joinedPath = Strings.join(path, '/');
       throw "Can't load $joinedPath from within $name: not a directory.";
     }
 
     var controller = new StreamController<List<int>>();
-    var tempDir;
-    // TODO(rnystrom): Use withTempDir() here.
     // TODO(nweiz): propagate any errors to the return value. See issue 3657.
-    createTempDir().then((_tempDir) {
-      tempDir = _tempDir;
-      return create(tempDir);
-    }).then((tar) {
-      var sourceStream = tar.openInputStream();
-      return store(wrapInputStream(sourceStream), controller).then((_) {
-        tempDir.delete(recursive: true);
+    withTempDir((tempDir) {
+      return create(tempDir).then((tar) {
+        var sourceStream = tar.openInputStream();
+        return store(wrapInputStream(sourceStream), controller);
       });
     });
     return new ByteStream(controller.stream);
   }
 }
 
 /// A descriptor that validates that no file exists with the given name.
 class NothingDescriptor extends Descriptor {
   NothingDescriptor(String name) : super(name);
 
@@ skipping 454 matching lines @@
 /// calling [completion] is unnecessary.
 void expectLater(Future actual, matcher, {String reason,
     FailureHandler failureHandler, bool verbose: false}) {
   _schedule((_) {
     return actual.then((value) {
       expect(value, matcher, reason: reason, failureHandler: failureHandler,
           verbose: false);
     });
   });
 }