chore(refactor): easier to make sense of attr-to-prop map (even if a bit reduntant)

modules/angular2/src/core/compiler/pipeline/element_binder_builder.js

@@ -91,26 +91,12 @@ function roleSetter(element, value) {
   }
 }
 
-// special mapping for cases where attribute name doesn't match property name
-var _lazyAttrToProp;
-
-function attrToProp() {
-  if (!isPresent(_lazyAttrToProp)) {
-    _lazyAttrToProp = StringMapWrapper.merge({
-      "inner-html": "innerHTML",
-      "readonly": "readOnly",
-      "tabindex": "tabIndex",
-    }, DOM.attrToPropMap);
-  }
-  return _lazyAttrToProp;
-}
-
 // tells if an attribute is handled by the ElementBinderBuilder step
 export function isSpecialProperty(propName:string) {
   return StringWrapper.startsWith(propName, ARIA_PREFIX)
         || StringWrapper.startsWith(propName, CLASS_PREFIX)
         || StringWrapper.startsWith(propName, STYLE_PREFIX)
-        || StringMapWrapper.contains(attrToProp(), propName);
+        || StringMapWrapper.contains(DOM.attrToPropMap, propName);
 }
 
 /**
@@ -257,7 +243,7 @@ export class ElementBinderBuilder extends CompileStep {
   }
 
   _resolvePropertyName(attrName:string) {
-    var mappedPropName = StringMapWrapper.get(attrToProp(), attrName);
+    var mappedPropName = StringMapWrapper.get(DOM.attrToPropMap, attrName);
     return isPresent(mappedPropName) ? mappedPropName : attrName;
   }
 }

modules/angular2/src/dom/browser_adapter.dart

@@ -18,10 +18,11 @@ class BrowserDomAdapter extends DomAdapter {
     setRootDomAdapter(new BrowserDomAdapter());
   }
 
-  // override JS logic of attribute to property mapping
   @override
   final attrToPropMap = const {
-    "inner-html": "innerHtml"
+    'inner-html': 'innerHtml',
+    'readonly': 'readOnly',
+    'tabindex': 'tabIndex',
   };
 
   query(String selector) => document.querySelector(selector);
@@ -108,13 +109,13 @@ class BrowserDomAdapter extends DomAdapter {
   createScriptTag(String attrName, String attrValue,
       [HtmlDocument doc = null]) {
     if (doc == null) doc = document;
-    var el = doc.createElement("SCRIPT");
+    var el = doc.createElement('SCRIPT');
     el.setAttribute(attrName, attrValue);
     return el;
   }
   StyleElement createStyleElement(String css, [HtmlDocument doc = null]) {
     if (doc == null) doc = document;
-    var el = doc.createElement("STYLE");
+    var el = doc.createElement('STYLE');
     el.text = css;
     return el;
   }

modules/angular2/src/dom/browser_adapter.es6

@@ -2,15 +2,19 @@ import {List, MapWrapper, ListWrapper} from 'angular2/src/facade/collection';
 import {isPresent} from 'angular2/src/facade/lang';
 import {DomAdapter, setRootDomAdapter} from './dom_adapter';
 
-var EMPTY_MAP = MapWrapper.create();
+var _attrToPropMap = {
+  'inner-html': 'innerHTML',
+  'readonly': 'readOnly',
+  'tabindex': 'tabIndex',
+};
 
 export class BrowserDomAdapter extends DomAdapter {
   static makeCurrent() {
     setRootDomAdapter(new BrowserDomAdapter());
   }
 
-  get attrToPropMap():Map {
-    return EMPTY_MAP
+  get attrToPropMap() {
+    return _attrToPropMap;
   }
 
   query(selector) {
@@ -75,7 +79,7 @@ export class BrowserDomAdapter extends DomAdapter {
     return res;
   }
   clearNodes(el) {
-    el.innerHTML = "";
+    el.innerHTML = '';
   }
   appendChild(el, node) {
     el.appendChild(node);
@@ -133,7 +137,7 @@ export class BrowserDomAdapter extends DomAdapter {
     return doc.createTextNode(text);
   }
   createScriptTag(attrName:string, attrValue:string, doc=document) {
-    var el = doc.createElement("SCRIPT");
+    var el = doc.createElement('SCRIPT');
     el.setAttribute(attrName, attrValue);
     return el;
   }

modules/angular2/src/dom/dom_adapter.js

@@ -15,9 +15,15 @@ function _abstract() {
  */
 @ABSTRACT()
 export class DomAdapter {
-  get attrToPropMap():Map {
+
+  /**
+   * Maps attribute names to their corresponding property names for cases
+   * where attribute name doesn't match property name.
+   */
+  get attrToPropMap() {
     throw _abstract();
   }
+
   parse(templateHtml:string) {
     throw _abstract();
   }