added printWarnings option to HtmlDiff

utils/apidoc/html_diff.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.
 
 /**
  * A script to assist in documenting the difference between the dart:html API
  * and the old DOM API.
  */
 #library('html_diff');
 
@@ skipping 33 matching lines @@
   final Map<Member, Set<Member>> htmlToDom;
 
   /** A map from `dart:dom` types to corresponding `dart:html` types. */
   final Map<Type, Set<Type>> domTypesToHtml;
 
   /** A map from `dart:html` types to corresponding `dart:dom` types. */
   final Map<Type, Set<Type>> htmlTypesToDom;
 
   final CommentMap comments;
 
+  /** If true, then print warning messages. */
+  final bool _printWarnings;
+
   static Library dom;
 
   /**
    * Perform static initialization of [world]. This should be run before
    * calling [HtmlDiff.run].
    */
   static void initialize() {
     world.getOrAddLibrary('dart:dom');
     world.getOrAddLibrary('dart:html');
     world.process();
 
     dom = world.libraries['dart:dom'];
   }
 
-  HtmlDiff() :
+  HtmlDiff([bool printWarnings = false]) : 
+    _printWarnings = printWarnings, 
     domToHtml = new Map<Member, Set<Member>>(),
     htmlToDom = new Map<Member, Set<Member>>(),
     domTypesToHtml = new Map<Type, Set<Type>>(),
     htmlTypesToDom = new Map<Type, Set<Type>>(),
     comments = new CommentMap();
 
+  void warn(String s) {
+    if (_printWarnings) {
+      print('Warning: ' + s);
+    }
+  }
+
   /**
    * Computes the `dart:dom` to `dart:html` mapping, and places it in
    * [domToHtml], [htmlToDom], [domTypesToHtml], and [htmlTypesToDom]. Before
    * this is run, Frog should be initialized (via [parseOptions] and
    * [initializeWorld]) and [HtmlDiff.initialize] should be called.
    */
   void run() {
     final htmlLib = world.libraries['dart:html'];
     for (Type htmlType in htmlLib.types.getValues()) {
       final domTypes = htmlToDomTypes(htmlType);
@@ skipping 17 matching lines @@
    * [implMember]'s defining [Type].
    */
   void _addMemberDiff(Member htmlMember, List<Type> domTypes) {
     if (htmlMember.isProperty) {
       if (htmlMember.canGet) _addMemberDiff(htmlMember.getter, domTypes);
       if (htmlMember.canSet) _addMemberDiff(htmlMember.setter, domTypes);
     }
 
     var domMembers = htmlToDomMembers(htmlMember, domTypes);
     if (htmlMember == null && !domMembers.isEmpty()) {
-      print('Warning: dart:html member ${htmlMember.declaringType.name}.' +
+      warn('dart:html member ${htmlMember.declaringType.name}.' +
           '${htmlMember.name} has no corresponding dart:html member.');
     }
 
     if (htmlMember == null) return;
     if (!domMembers.isEmpty()) htmlToDom[htmlMember] = domMembers;
     domMembers.forEach((m) =>
         domToHtml.putIfAbsent(m, () => new Set()).add(htmlMember));
   }
 
   /**
    * Returns the `dart:dom` [Type]s that correspond to [htmlType] from
    * `dart:html`. This can be the empty list if no correspondence is found.
    */
   List<Type> htmlToDomTypes(Type htmlType) {
     if (htmlType.name == null) return [];
     final tags = _getTags(comments.find(htmlType.span));
 
     if (tags.containsKey('domName')) {
       var domNames = map(tags['domName'].split(','), (s) => s.trim());
       if (domNames.length == 1 && domNames[0] == 'none') return [];
       return map(domNames, (domName) {
         final domType = dom.types[domName];
-        if (domType == null) print('Warning: no dart:dom type named $domName');
+        if (domType == null) warn('no dart:dom type named $domName');
         return domType;
       });
     }
     return <Type>[];
   }
 
   /**
    * Returns the `dart:dom` [Member]s that correspond to [htmlMember] from
    * `dart:html`. This can be the empty set if no correspondence is found.
    * [domTypes] are the `dart:dom` [Type]s that correspond to [implMember]'s
    * defining [Type].
    */
   Set<Member> htmlToDomMembers(Member htmlMember, List<Type> domTypes) {
     if (htmlMember.isPrivate) return new Set();
     final tags = _getTags(comments.find(htmlMember.span));
     if (tags.containsKey('domName')) {
       final domNames = map(tags['domName'].split(','), (s) => s.trim());
       if (domNames.length == 1 && domNames[0] == 'none') return new Set();
       final members = new Set();
       domNames.forEach((name) {
         var nameMembers = _membersFromName(name, domTypes);
         if (nameMembers.isEmpty()) {
           if (name.contains('.')) {
-            print('Warning: no member $name');
+            warn('no member $name');
           } else {
             final options = Strings.join(
                 map(domTypes, (t) => "${t.name}.$name"), ' or ');
-            print('Warning: no member $options');
+            warn('no member $options');
           }
         }
         members.addAll(nameMembers);
       });
       return members;
     }
 
     return new Set();
   }
 
   /**
    * Returns the `dart:dom` [Member]s that are indicated by [name]. [name] can
    * be either an unqualified member name (e.g. `createElement`), in which case
    * it's treated as the name of a member of one of [defaultTypes], or a
    * fully-qualified member name (e.g. `Document.createElement`), in which case
    * it's looked up in `dart:dom` and [defaultTypes] is ignored.
    */
   Set<Member> _membersFromName(String name, List<Type> defaultTypes) {
     if (!name.contains('.', 0)) {
       if (defaultTypes.isEmpty()) {
-        print('Warning: no default type for ${name}');
+        warn('no default type for ${name}');
         return new Set();
       }
       final members = new Set<Member>();
       defaultTypes.forEach((t) {
         if (t.members.containsKey(name)) members.add(t.members[name]);
       });
       return members;
     }
 
     final splitName = name.split('.');
     if (splitName.length != 2) {
-      print('Warning: invalid member name ${name}');
+      warn('invalid member name ${name}');
       return new Set();
     }
 
     var typeName = splitName[0];
 
     final type = dom.types[typeName];
     if (type == null) return new Set();
 
     final member = type.members[splitName[1]];
     if (member == null) return new Set();
@@ skipping 12 matching lines @@
   Map<String, String> _getTags(String comment) {
     if (comment == null) return const <String>{};
     final re = const RegExp("@([a-zA-Z]+) ([^;]+)(?:;|\$)");
     final tags = <String>{};
     for (var m in re.allMatches(comment.trim())) {
       tags[m[1]] = m[2];
     }
     return tags;
   }
 }