Allow a single translation to be from multiple differently-named sources

pkg/intl/test/message_extraction/generate_from_json.dart

 #!/usr/bin/env dart
 // Copyright (c) 2013, 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.
 
 /**
  * A main program that takes as input a source Dart file and a number
  * of JSON files representing translations of messages from the corresponding
  * Dart file. See extract_to_json.dart and make_hardcoded_translation.dart.
  *
@@ skipping 10 matching lines @@
 import 'package:intl/src/intl_message.dart';
 import 'package:intl/generate_localized.dart';
 import 'package:path/path.dart' as path;
 import 'package:args/args.dart';
 import 'package:serialization/serialization.dart';
 
 /**
  * Keeps track of all the messages we have processed so far, keyed by message
  * name.
  */
-Map<String, MainMessage> messages;
+Map<String, List<MainMessage>> messages;
 
 main(List<String> args) {
   var targetDir;
   var parser = new ArgParser();
   parser.addFlag("suppress-warnings", defaultsTo: false,
       callback: (x) => suppressWarnings = x);
   parser.addOption("output-dir", defaultsTo: '.',
       callback: (x) => targetDir = x);
   parser.addOption("generated-file-prefix", defaultsTo: '',
       callback: (x) => generatedFilePrefix = x);
   parser.parse(args);
   var dartFiles = args.where((x) => x.endsWith("dart")).toList();
   var jsonFiles = args.where((x) => x.endsWith(".json")).toList();
   if (dartFiles.length == 0 || jsonFiles.length == 0) {
     print('Usage: generate_from_json [--output-dir=<dir>]'
         ' [--generated-file-prefix=<prefix>] file1.dart file2.dart ...'
         ' translation1.json translation2.json ...');
     exit(0);
   }
 
   // We're re-parsing the original files to find the corresponding messages,
   // so if there are warnings extracting the messages, suppress them.
   suppressWarnings = true;
   var allMessages = dartFiles.map((each) => parseFile(new File(each)));
 
   messages = new Map();
   for (var eachMap in allMessages) {
-    eachMap.forEach((key, value) => messages[key] = value);
+    eachMap.forEach((key, value) =>
+        messages.putIfAbsent(key, () => []).add(value));
   }
   for (var arg in jsonFiles) {
     var file = new File(arg);
     generateLocaleFile(file, targetDir);
   }
 
   var mainImportFile = new File(path.join(targetDir,
       '${generatedFilePrefix}messages_all.dart'));
   mainImportFile.writeAsStringSync(generateMainImportFile());
 }
@@ skipping 29 matching lines @@
   data.forEach((key, value) {
     if (key[0] != "_") {
       translations.add(new BasicTranslatedMessage(key, value));
     }
   });
   generateIndividualMessageFile(locale, translations, targetDir);
 }
 
 /**
  * A TranslatedMessage that just uses the name as the id and knows how to look
- * up its original message in our [messages].
+ * up its original messages in our [messages].
  */
 class BasicTranslatedMessage extends TranslatedMessage {
   BasicTranslatedMessage(String name, translated) :
       super(name, translated);
 
-  MainMessage get originalMessage =>
-      (super.originalMessage == null) ? _findOriginal() : super.originalMessage;
+  List<MainMessage> get originalMessages => (super.originalMessages == null) ?
+      _findOriginals() : super.originalMessages;
 
   // We know that our [id] is the name of the message, which is used as the
   //key in [messages].
-  MainMessage _findOriginal() => originalMessage = messages[id];
+  List<MainMessage> _findOriginals() => originalMessages = messages[id];
 }