Specs: registerElement(registerElement(...)) failed to work as expected

sky/examples/htmlish/framework/element.sky

 SKY MODULE - defines an <element> element
 <import src="sky:core" as="sky"/>
 
 <!-- usage:
 
    <element name="tagname">
     <style> style here (optional) </style>
     <template> shadow tree here (optional) </template>
     <script> // optional
      module.currentScript.parentNode.setPrototype({
        init: function () {
          // constructor here
        },
        // rest of api here
      });
     </script>
    </element>
 
 -->
 
 <script>
- module.exports.Element = sky.registerElement({
-   tagName: 'element',
-   constructor: class extends Element {
+ module.exports.Element = sky.registerElement(
+   class extends Element {
+     static get tagName() { return 'element'; }
      constructor (module) {
        super();
        this.state = 'loading';
        this.module = module;
        this.definedPrototype = sky.Element;
      }
      setPrototype(prototype) {
        this.definedPrototype = prototype;
      }
      endTagParsedCallback() {
@@ skipping 16 matching lines @@
          if (style)
            this.shadowRoot.append(style.cloneNode(true));
          if (template)
            this.shadowRoot.append(template.cloneNode(true));
          }
        };
        if (this.definedPrototype)
          constructor.prototype = this.definedPrototype;
        else
          constructor.prototype = sky.Element;
-       this.module.exports[constructorName] = this.registerElement({
-         tagName: this.getAttribute('name'),
-         shadow: style || template,
-         constructor: constructor,
-       });
+       constructor.tagName = this.getAttribute('name');
+       constructor.shadow = style || template;
+       this.module.exports[constructorName] = this.registerElement(constructor);
        delete this.definedPrototype;
        delete this.module;
        this.state = 'loaded';
      }
-   },
- });
+   }
+ );
 </script>