Updated json_to_html to be sync.

tools/html_json_doc/lib/html_to_json.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.
 
 /**
  * Library for extracting the documentation comments from files generated by
  * the HTML library. The comments are stored in a JSON file.
  *
  * Comments must be in either the block style with leading *s:
  *
@@ skipping 30 matching lines @@
   // TODO(amouravski): make this transform once I know what I want this file to
   // return.
   _convertFiles(htmlPath).then((convertedJson) {
     final jsonFile = new File.fromPath(jsonPath);
     var writeJson = convertedJson;
 
     if (jsonFile.existsSync()) {
       writeJson = _mergeJsonAndFile(convertedJson, jsonFile);
     }
 
-    var outputStream = jsonFile.openOutputStream();
-    outputStream.writeString(prettyPrintJson(writeJson));
-
-    outputStream.onNoPendingWrites = () {
-      completer.complete(_anyErrors);
-    };
-
-    outputStream.onClosed = () {
-      completer.complete(_anyErrors);
-    };
-    
-    outputStream.onError = completer.completeException;
+    jsonFile.writeAsStringSync(prettyPrintJson(writeJson));
+    completer.complete(_anyErrors);
   });
 
   return completer.future;
 }
 
 
 /**
  * Convert all files on [htmlPath].
  *
  * Returns a future that completes to the converted JSON object.
  */
 Future<Object> _convertFiles(Path htmlPath) {
-  var completer = new Completer();
-
-  List<Future> fileFutures = [];
+  //List<Future> fileFutures = [];

[Emily Fortuna, 2012/11/28 17:17:30]

probably just delete this line if it's going to be commented out.

+  var group = new FutureGroup();
 
   // Get a list of all HTML dart files.
   // TODO(amouravski): discriminate .dart files.
   final htmlDir = new Directory.fromPath(htmlPath);
   final lister = htmlDir.list(recursive: false);
 
+  var listCompleter = new Completer();
+  group.add(listCompleter.future);
+
   lister.onFile = (String path) {
     final name = new Path.fromNative(path).filename;
 
     // Ignore private classes.
     if (name.startsWith('_')) return;
 
     // Ignore non-dart files.
     if (!name.endsWith('.dart')) return;
 
-    File file = new File(path);
-
-    // TODO(amouravski): Handle missing file.
-    if (!file.existsSync()) {
-      print('ERROR: cannot find file $path');
-      _anyErrors = true;
-      return;
-    }
-
-    fileFutures.add(_convertFile(file));
+    group.add(_convertFile(path));
+    //fileFutures.add(_convertFile(file));

[Emily Fortuna, 2012/11/28 17:17:30]

ditto here.

   };
 
 
   // Combine all JSON objects
-  lister.onDone = (_) {
-    Futures.wait(fileFutures).then((jsonList) {
-      var convertedJson = {};
-      jsonList.forEach((json) {
-        final k = json.keys[0];
-        convertedJson.putIfAbsent(k, () => json[k]);
-      });
-      completer.complete(convertedJson);
-    });
+  lister.onDone = (done) {
+    if (done) listCompleter.complete(null);
+//    Futures.wait(fileFutures).then((jsonList) {

[Emily Fortuna, 2012/11/28 17:17:30]

and here

+//      var convertedJson = {};
+//      jsonList.forEach((json) {
+//        final k = json.keys[0];
+//        convertedJson.putIfAbsent(k, () => json[k]);
+//      });
+//      completer.complete(convertedJson);
+//    });
   };
 
   // TODO(amouravski): add more error handling.
 
-  return completer.future;
+  return group.future.transform((values) {
+      var convertedJson = {};
+      values.forEach((json) {
+        final k = json.keys[0];
+        convertedJson.putIfAbsent(k, () => json[k]);
+      });
+
+      return convertedJson;
+  });
+
+  //return completer.future;

[Emily Fortuna, 2012/11/28 17:17:30]

same

 }
 
 
 /**
  * Convert a single file to JSON docs.
  *
  * Returns a map with one entry whose key is the file name and whose value is
  * the list of comment lines.
  */
-Future<Map> _convertFile(File file) {
+Future<Map> _convertFile(String path) {
+  File file = new File(path);
+
+  // TODO(amouravski): Handle missing file.
+  if (!file.existsSync()) {
+    print('ERROR: cannot find file $path');
+    _anyErrors = true;
+    return;
+  }
+
   var completer = new Completer();
 
   var comments = {};
 
-  // Find all /// @docsEditable annotations.
-  InputStream file_stream = file.openInputStream();
-  StringInputStream inputLines = new StringInputStream(file_stream);
-
-  // TODO(amouravski): Re-write as file.readAsLine().thin((lines) {...}
-  inputLines.onLine = () {
+  file.readAsLines().then((lines) {
     var comment = <String>[];
 
     var docCommentFound = false;
     String line;
-    while ((line = inputLines.readLine()) != null) {
+    while (!lines.isEmpty && (line = lines.removeAt(0)) != null) {
       var trimmedLine = line.trim();
 
       // Sentinel found. Process the comment block.
       if (trimmedLine.startsWith('///') &&
           trimmedLine.contains('@docsEditable')) {
         if (docCommentFound == true) {
-          var nextLine = inputLines.readLine();
+          var nextLine = lines.removeAt(0);
 
           if (nextLine == null) return false;
 
           var lineObject = {};
 
           if (comments[nextLine] != null) {
             print('WARNING: duplicate line ${nextLine} found in'
                 '${new Path(file.fullPathSync()).filename}');
           }
           comments.putIfAbsent(nextLine, () => comment);
@@ skipping 12 matching lines @@
           // /// blah
           // *
           (trimmedLine.startsWith('*') || trimmedLine.startsWith('///'))) {
         comment.add(line);
       } else {
         // Reset if we're not in a comment.
         docCommentFound = false;
         comment = <String>[];
       }
     }
-  };
 
-  inputLines.onClosed = () {
     var jsonObject = {};
     jsonObject[new Path(file.fullPathSync()).filename] = comments;
     completer.complete(jsonObject);
-  };
+  });
 
   // TODO(amouravski): better error handling.
 
   return completer.future;
 }
 
 
 /**
  * Merge the new JSON object and the existing file.
  */
@@ skipping 102 matching lines @@
         '$indentation${JSON.stringify(key)}:\n'
         '${prettyPrintJson(json[key], '$indentation  ')}');
     var recursiveOutput = Strings.join(mapList, ',\n');
     output = '$indentation{\n'
       '$recursiveOutput'
       '\n$indentation}';
   } else {
     output = '$indentation${JSON.stringify(json)}';
   }
   return output;
-}
+}
+/** A completer that waits until all added [Future]s complete. */

[Emily Fortuna, 2012/11/28 17:17:30]

add a blank newline before this line

+class FutureGroup {
+  const _FINISHED = -1;
+  int _pending = 0;
+  Completer<List> _completer = new Completer<List>();
+  final List<Future> futures = <Future>[];
+  final List output = [];
+
+  /**
+   * Wait for [task] to complete (assuming this barrier has not already been
+   * marked as completed, otherwise you'll get an exception indicating
+   * that a
+   * future has already been completed).
+   */
+  void add(Future task) {
+    if (_pending == _FINISHED) {
+      throw new FutureAlreadyCompleteException();
+    }
+    _pending++;
+    futures.add(task);
+    task.handleException(
+        (e) => _completer.completeException(e, task.stackTrace));
+    task.then((value) {
+        if (value != null) output.add(value);
+        _pending--;
+        if (_pending == 0) {
+          _pending = _FINISHED;
+          _completer.complete(output);
+        }
+    });
+  }
+
+  Future<List> get future => _completer.future;
+}