Add support for previewComment in Typedef

client/lib/item.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.
 
 library category_item;
 
 import 'dart:async';
 import 'dart:convert';
 
 import 'package:dartdoc_viewer/data.dart';
 import 'package:dartdoc_viewer/read_yaml.dart';
 import 'package:polymer/polymer.dart';
 import 'package:yaml/yaml.dart';
 import 'package:dartdoc_viewer/location.dart';
 import 'package:dartdoc_viewer/search.dart' show searchIndex;
 import 'package:collection/equality.dart';
 
 // TODO(tmandel): Don't hardcode in a path if it can be avoided.
 @reflectable const docsPath = 'docs/';
 
-nothing() => null;
+_returnNull() => null;
 
 /**
  * Abstract class for anything that holds values and can be displayed.
  */
 @reflectable class Container extends Observable {
   final String name;
   @observable String comment = '<span></span>';
   bool get hasComment => !hasNoComment;
   bool get hasNoComment =>
       comment == '<span></span>' || comment == '<div></div>';
 
   Container(this.name, [this.comment]);
 
   String toString() => "$runtimeType($name)";
 }
 
 /** Wraps a comment in span element to make it a single HTML Element. */
 String _wrapComment(String comment) =>
     comment == null ? '<div></div>' : '<div>$comment</div>';
 
 /**
  * A [Container] that contains other [Container]s to be displayed.
  */
 @reflectable class Category extends Container {
   List<Container> content = [];
   Set<String> memberNames = new Set<String>();
   int inheritedCounter = 0;
   int memberCounter = 0;
 
-  Item memberNamed(String name, {orElse : nothing}) =>
+  Item memberNamed(String name, {orElse : _returnNull}) =>
       content.firstWhere((x) => x.name == name, orElse: orElse);
 
   Category.forClasses(List<Map> classes, String name,
       {bool isAbstract: false}) : super(name) {
     if (classes != null) {
       classes.forEach((clazz) =>
         content.add(new Class.forPlaceholder(clazz['qualifiedName'],
             clazz['preview'])));
     }
   }
@@ skipping 170 matching lines @@
   /// For non-inherited items, this will just be the [location].
   DocsLocation get localLocation => location;
 
   String get anchorHref => Uri.encodeFull(anchorHrefLocation.withAnchor);
 
   /// [anchorHref] but with the leading # separator.
   String get prefixedAnchorHref => locationPrefixed(anchorHref);
 
   bool get isLoaded => true;
 
-  Item memberNamed(String name, {Function orElse : nothing}) => nothing();
+  Item memberNamed(String name, {Function orElse : _returnNull}) => _returnNull();
 
   Item get owner => _owner == null ?
       _owner = pageIndex[location.parentQualifiedName] : _owner;
 
   /// Return true if [possibleOwner] is anywhere in our chain of owners.
   bool isOwnedBy(Item possibleOwner) {
     if (owner == null || possibleOwner == null) return false;
     if (owner == possibleOwner) return true;
     return owner.isOwnedBy(possibleOwner);
   }
@@ skipping 94 matching lines @@
       libraries..remove(mainLib)..insert(0, mainLib);
       var libs = yaml['libraries'];
       var main = libs.firstWhere((each) => each['name'] == mainLib.name);
       var intro = main['packageIntro'];
       if (intro != null && !intro.isEmpty) {
         comment = _wrapComment(intro);
       }
     }
   }
 
-  Item memberNamed(String name, {Function orElse : nothing}) {
+  Item memberNamed(String name, {Function orElse : _returnNull}) {
     return libraries.firstWhere(
         (each) => each.name == name || each.decoratedName == name,
         orElse: orElse);
   }
 }
 
 /// Runs through the member structure and creates path information.
 @reflectable void buildHierarchy(Item page, Item previous) {
   if (page.path.isEmpty) {
     page.path
         ..addAll(previous.path)
         ..add(page);
   }
   page.addToHierarchy();
 }
 
 /**
  * An [Item] that is lazily loaded.
  */
 @reflectable abstract class LazyItem extends Item {
   bool isLoaded = false;
-  String previewComment;
+  final String previewComment;
 
-  LazyItem(String qualifiedName, String name, previewComment,
-      [String comment]) : previewComment = previewComment ,
-      super(name, qualifiedName, comment);
+  LazyItem(String qualifiedName, String name, this.previewComment,
+      [String comment])
+      : super(name, qualifiedName, comment);
 
   /// Loads this [Item]'s data and populates all fields.
   Future load() {
     if (isLoaded) return new Future.value(this);
     var location = '$docsPath$qualifiedName.' + (isYaml ? 'yaml' : 'json');
     var data = retrieveFileContents(location);
     return data.then((response) {
       var yaml = isYaml ? loadYaml(response) : JSON.decode(response);
       loadValues(yaml);
       buildHierarchy(this, this);
@@ skipping 67 matching lines @@
   }
 
   String get decoratedName {
     return isDartLibrary ?
         name.replaceAll('-dom-', '-').replaceAll('-', ':') :
         name.replaceAll('-', '.');
   }
 
   bool get isDartLibrary => home != null && home.isTopLevelHome;
 
-  Item memberNamed(String name, {Function orElse : nothing}) {
+  Item memberNamed(String name, {Function orElse : _returnNull}) {
     if (name == null || !isLoaded) return orElse();
     for (var category in
         [classes, functions, variables, operators, typedefs, errors]) {
-      var member = category.memberNamed(name, orElse: nothing);
+      var member = category.memberNamed(name, orElse: _returnNull);
       if (member != null) return member;
     }
     return orElse();
   }
 }
 
 /**
  * An [Item] that describes a single Dart class.
  */
 @reflectable class Class extends LazyItem {
@@ skipping 159 matching lines @@
     var out = new StringBuffer();
     out.write(name);
     if (generics.isNotEmpty) {
       // Use a non-breaking space character, not &nbsp; because this will
       // get escaped.
       out.writeAll(["<", generics.join(",\u{00A0}"), ">"]);
     }
     return out.toString();
   }
 
-  Item memberNamed(String name, {Function orElse : nothing}) {
+  Item memberNamed(String name, {Function orElse : _returnNull}) {
     if (name == null) return orElse();
     for (var category in
         [annotations, constructs, functions, operators, variables]) {
       var member =  category == null ? null :
-          category.memberNamed(name, orElse: nothing);
+          category.memberNamed(name, orElse: _returnNull);
       if (member != null) return member;
     }
     return orElse();
   }
 
 }
 
 /**
  * A collection of [Annotation]s.
  */
 @reflectable class AnnotationGroup {
   List<String> supportedBrowsers = [];
   List<Annotation> annotations = [];
   String domName;
 
-  Item memberNamed(String name, {Function orElse : nothing}) =>
+  Item memberNamed(String name, {Function orElse : _returnNull}) =>
     annotations.firstWhere((a) => a.qualifiedName == name, orElse: orElse);
 
   AnnotationGroup(List annotes) {
     var set = new Set();
     if (annotes != null) {
       annotes.forEach((annotation) {
         if (annotation['name'].endsWith('.SupportedBrowser')) {
           supportedBrowsers.add(annotation['parameters'].toList().join(' '));
         } else if (annotation['name'].endsWith('.DomName')) {
           domName = annotation['parameters'].first;
@@ skipping 49 matching lines @@
       parameters.forEach((name, data) {
         values.add(new Parameter(name, data, this));
       });
     }
     return values;
   }
 
   Parameter parameterNamed(String name) =>
       parameters.firstWhere((x) => x.name == name, orElse: () => null);
 
-  Item memberNamed(String name, {Function orElse : nothing}) {
+  Item memberNamed(String name, {Function orElse : _returnNull}) {
     var result = parameterNamed(name);
     return result == null ? orElse() : result;
   }
 }
 
 /**
  * An [Item] that describes a single Dart typedef.
  */
 @reflectable class Typedef extends Parameterized {
-  LinkableType type;
-  AnnotationGroup annotations;
+  final LinkableType type;
+  final AnnotationGroup annotations;
+  final String previewComment;
 
-  Typedef(Map yaml) : super(yaml['name'], yaml['qualifiedName'],
-      _wrapComment(yaml['comment'])) {
-    type = new LinkableType(yaml['return']);
+  Typedef(Map yaml)
+      : type = new LinkableType(yaml['return']),
+        annotations = new AnnotationGroup(yaml['annotations']),
+        previewComment = yaml['preview'],
+        super(yaml['name'], yaml['qualifiedName'],
+            _wrapComment(yaml['comment'])) {
     parameters = getParameters(yaml['parameters']);
-    annotations = new AnnotationGroup(yaml['annotations']);
   }
 }
 
 /**
  * An [Item] that describes a single Dart method.
  */
 @reflectable class Method extends Parameterized {
   bool isStatic;
   bool isAbstract;
   bool isConstant;
@@ skipping 235 matching lines @@
 }
 
 
 bool _boolFor(String key, Map input) {
   var value = input[key];
   if (value == true || value == 'true') return true;
   if (value == null || value == false || value == 'false') return false;
   throw new FormatException("Invalid format, expected boolean key: $key"
       " value: $value");
 }