Change dart:io to use Future for one-shot operations.

lib/dartdoc/dartdoc.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.
 
 /**
  * To generate docs for a library, run this script with the path to an
  * entrypoint .dart file, like:
  *
  *     $ dart dartdoc.dart foo.dart
  *
@@ skipping 147 matching lines @@
 /**
  * Copies all of the files in the directory [from] to [to]. Does *not*
  * recursively copy subdirectories.
  *
  * Note: runs asynchronously, so you won't see any files copied until after the
  * event loop has had a chance to pump (i.e. after `main()` has returned).
  */
 Future copyFiles(String from, String to) {
   final completer = new Completer();
   final fromDir = new Directory(from);
-  fromDir.onFile = (path) {
+  final lister = fromDir.list(recursive: false);
+
+  lister.onFile = (path) {
     final name = basename(path);
     // TODO(rnystrom): Hackish. Ignore 'hidden' files like .DS_Store.
     if (name.startsWith('.')) return;
 
-    new File(path).readAsBytes((bytes) {
+    new File(path).readAsBytes().then((bytes) {
       final outFile = new File('$to/$name');
       final stream = outFile.openOutputStream(FileMode.WRITE);
       stream.write(bytes, copyBuffer: false);
       stream.close();
     });
   };
-  fromDir.onDone = (done) => completer.complete(true);
-  fromDir.list(recursive: false);
+  lister.onDone = (done) => completer.complete(true);
   return completer.future;
 }
 
 /**
  * Compiles the given Dart script to a JavaScript file at [jsPath] using the
  * Dart-to-JS compiler located at [compilerPath].
  */
 Future compileScript(String compilerPath, String libDir,
     String dartPath, String jsPath) {
   final completer = new Completer();
-  onExit(int exitCode, String stdout, String stderr) {
-    if (exitCode != 0) {
+  onExit(ProcessResult result) {
+    if (result.exitCode != 0) {
       final message = 'Non-zero exit code from $compilerPath';
       print('$message.');
-      print(stdout);
-      print(stderr);
+      print(result.stdout);
+      print(result.stderr);
       throw message;
     }
     completer.complete(true);
   }
 
   onError(error) {
     final message = 'Error trying to execute $compilerPath. Error: $error';
     print('$message.');
     throw message;
   }
 
   print('Compiling $dartPath to $jsPath');
-  new Process.run(compilerPath, [
+  var processFuture = Process.run(compilerPath, [
     '--libdir=$libDir', '--out=$jsPath',
     '--compile-only', '--enable-type-checks', '--warnings-as-errors',
-    dartPath], null, onExit).onError = onError;
+    dartPath]);
+
+  processFuture.handleException(onError);
+  processFuture.then(onExit);
+
   return completer.future;
 }
 
 class Dartdoc {
 
   /** Set to `false` to not include the source code in the generated docs. */
   bool includeSource = true;
 
   /**
    * Dartdoc can generate docs in a few different ways based on how dynamic you
@@ skipping 1120 matching lines @@
       if (filename.endsWith('appcache.manifest')) {
         return;
       }
       var relativePath = filename.substring(pathPrefixLength + 1);
       write("$relativePath\n");
     };
     toCache.onDone = (done) => endFile();
     toCache.list(recursive: true);
   }
 }