Merge pull request #581 from kevmoo/polymer

lib/src/messages.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 messages;
 
 import 'dart:json' as json;
 
+import 'package:barback/barback.dart' show TransformLogger;
 import 'package:source_maps/span.dart' show Span;
 import 'package:logging/logging.dart' show Level;
 
 import 'compiler_options.dart';
 import 'utils.dart';
 
 /** Map between error levels and their display color. */
 final Map<Level, String> _ERROR_COLORS = (() {
   var colorsMap = new Map<Level, String>();
   colorsMap[Level.SEVERE] = RED_COLOR;
@@ skipping 44 matching lines @@
         'charEnd': span.end.offset,
       }
     }]);
   }
 }
 
 /**
  * This class tracks and prints information, warnings, and errors emitted by the
  * compiler.
  */
-class Messages {
+class Messages implements TransformLogger {
   final CompilerOptions options;
   final bool shouldPrint;
 
   final List<Message> messages = <Message>[];
 
   Messages({CompilerOptions options, this.shouldPrint: true})
       : options = options != null ? options : new CompilerOptions();
 
   /**
    * Creates a new instance of [Messages] which doesn't write messages to
@@ skipping 10 matching lines @@
   // Convenience methods for testing
   int get length => messages.length;
 
   Message operator[](int index) => messages[index];
 
   void clear() {
     messages.clear();
   }
 
   /** [message] is considered a static compile-time error by the Dart lang. */
-  void error(String message, Span span) {
+  void error(String message, [Span span]) {
     var msg = new Message(Level.SEVERE, message, span: span,
         useColors: options.useColors);
 
     messages.add(msg);
     printMessage(msg);
   }
 
   /** [message] is considered a type warning by the Dart lang. */
-  void warning(String message, Span span) {
+  void warning(String message, [Span span]) {
     if (options.warningsAsErrors) {
       error(message, span);
     } else {
       var msg = new Message(Level.WARNING, message,
           span: span, useColors: options.useColors);
 
       messages.add(msg);
       printMessage(msg);
     }
   }
 
   /// the list of error messages. Empty list, if there are no error messages.
   List<Message> get errors =>
         messages.where((m) => m.level == Level.SEVERE).toList();
 
   /// the list of warning messages. Empty list if there are no warning messages.
   List<Message> get warnings =>
         messages.where((m) => m.level == Level.WARNING).toList();
 
   /**
    * [message] at [span] will tell the user about what the compiler
    * is doing.
    */
-  void info(String message, Span span) {
+  void info(String message, [Span span]) {
     var msg = new Message(Level.INFO, message, span: span,
         useColors: options.useColors);
 
     messages.add(msg);
     if (options.verbose) printMessage(msg);
   }
 
   void printMessage(msg) {
     if (shouldPrint) print(options.jsonFormat ? msg.toJson() : msg);
   }
 }