Reducing the amount of code we generate in the compiler: We still continue

lib/custom_element.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 polymer.custom_element;
 
 import 'dart:async';
 import 'dart:html';
 import 'package:mdv/mdv.dart' as mdv;
 import 'package:meta/meta.dart';
@@ skipping 30 matching lines @@
   if (_customElements.containsKey(localName)) {
     throw new ArgumentError('custom element $localName already registered.');
   }
 
   // TODO(jmesserly): validate this is a valid tag name, not a selector.
   _customElements[localName] = create;
 
   // Initialize elements already on the page.
   for (var query in [localName, '[is=$localName]']) {
     for (var element in document.queryAll(query)) {
-      _initCustomElement(element, create);
+      _initCustomElement(element, localName, create);
     }
   }
 }
 
 /**
  * The base class for all Dart web components. In addition to the [Element]
  * interface, it also provides lifecycle methods:
  * - [created]
  * - [inserted]
  * - [attributeChanged]
@@ skipping 53 matching lines @@
   }
 
   // TODO(sigmund): delete this. We should techincally only call this method
   // on subclasses of polymer element. To delete this we either make this method
   // private in PolymerElement, stop doing compilation, or add support for the
   // polymer-element tag.
   void shadowRootReady(ShadowRoot root, String elementName) {}
 
   getShadowRoot(String componentName) => _generatedRoots[componentName];
 
-  /** Any CSS selector (class, id or element) defined name to mangled name. */
-  ScopedCssMapper _mapper = new ScopedCssMapper({});
-
-  // TODO(terry): Add a mapper per component in the type hierarchy.
-  ScopedCssMapper getScopedCss(String componentName) => _mapper;
-  void setScopedCss(String componentName, ScopedCssMapper mapper) {
-    _mapper = mapper;
-  }
 
   /**
    * *Warning*: This is an implementation helper for Custom Elements and
    * should not be used in your code.
    *
    * Clones the template, instantiates custom elements and hooks events, then
    * returns it.
    */
   DocumentFragment cloneTemplate(DocumentFragment shadowTemplate) {
     var result = shadowTemplate.clone(true);
@@ skipping 37 matching lines @@
   void inserted() {}
 
   /** Invoked when this component is removed from the DOM tree. */
   void removed() {}
 
   // TODO(jmesserly): how do we implement this efficiently?
   // See https://github.com/dart-lang/web-ui/issues/37
   /** Invoked when any attribute of the component is modified. */
   void attributeChanged(String name, String oldValue, String newValue) {}
 
-  /**
-   * **Note**: This is an implementation helper and should not need to be calle
-   * from your code.
-   *
-   * Initializes the contents of the ShadowRoot from template inside the
-   * `<element>` element.
-   */
-  void initShadow() {}
-
   get model => host.model;
 
   void set model(newModel) {
     host.model = newModel;
   }
 
   get templateInstance => host.templateInstance;
   get isTemplate => host.isTemplate;
   get ref => host.ref;
   get content => host.content;
@@ skipping 408 matching lines @@
   Stream<TouchEvent> get onTouchMove => host.onTouchMove;
   Stream<TouchEvent> get onTouchStart => host.onTouchStart;
   Stream<TransitionEvent> get onTransitionEnd => host.onTransitionEnd;
 
   // TODO(sigmund): do the normal forwarding when dartbug.com/7919 is fixed.
   Stream<WheelEvent> get onMouseWheel {
     throw new UnsupportedError('onMouseWheel is not supported');
   }
 }
 
-/**
- * Maps CSS selectors (class and) to a mangled name and maps x-component name
- * to [is='x-component'].
- */
-class ScopedCssMapper {
-  final Map<String, String> _mapping;
-
-  ScopedCssMapper(this._mapping);
-
-  /** Returns mangled name of selector sans . or # character. */
-  String operator [](String selector) => _mapping[selector];
-
-  /** Returns mangled name of selector w/ . or # character. */
-  String getSelector(String selector) {
-    var prefixedName = this[selector];
-    var selectorType = selector[0];
-    if (selectorType == '.' || selectorType == '#') {
-      return '$selectorType${prefixedName}';
-    }
-
-    return prefixedName;
-  }
-}
 
 typedef DocumentFragmentCreated(DocumentFragment fragment);
 
 Map<String, Function> _customElements;
 
 void _createElements(Node node) {
   for (var c = node.firstChild; c != null; c = c.nextNode) {
     _createElements(c);
   }
   if (node is Element) {
-    var ctor = _customElements[node.localName];
+    var name = node.localName;
+    var ctor = _customElements[name];
     if (ctor == null) {
-      var isAttr = node.attributes['is'];
-      if (isAttr != null) ctor = _customElements[isAttr];
+      name = node.attributes['is'];
+      if (name != null) ctor = _customElements[name];
     }
-    if (ctor != null) _initCustomElement(node, ctor);
+    if (ctor != null) _initCustomElement(node, name, ctor);
   }
 }
 
-void _initCustomElement(Element node, CustomElement ctor()) {
+void _initCustomElement(Element node, String localName, CustomElement ctor()) {

[Jennifer Messerly, 2013/07/18 23:56:04]

do we need this arg?

[Siggi Cherem (dart-lang), 2013/07/19 22:52:52]

oops, not anymore =) I removed the use of it, but forgot to remove it. Thanks.

   CustomElement element = ctor();
   element.host = node;
 
   // TODO(jmesserly): replace lifecycle stuff with a proper polyfill.
-  element..initShadow()..created();
+  element.created();
 
   _registerLifecycleInsert(element);
 }
 
 void _registerLifecycleInsert(CustomElement element) {
   runAsync(() {
     // TODO(jmesserly): bottom up or top down insert?
     var node = element.host;
 
     // TODO(jmesserly): need a better check to see if the node has been removed.
@@ skipping 25 matching lines @@
 /**
  * DEPRECATED: this has no effect. Shadow DOM should always be used with custom
  * elements.
  *
  * Set this to true to use native Shadow DOM if it is supported.
  * Note that this will change behavior of [WebComponent] APIs for tree
  * traversal.
  */
 @deprecated
 bool useShadowDom = false;