[webcomponents] [Custom]: Specify preference of localName and typeExtension in createElement (bugzilla: 26852) (#167)

Title: [Custom]: Specify preference of localName and typeExtension in createElement (bugzilla: 26852)

Migrated from: https://www.w3.org/Bugs/Public/show_bug.cgi?id=26852

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comment: 0
comment_url: https://www.w3.org/Bugs/Public/show_bug.cgi?id=26852#c0
*Deepak Singla* wrote on 2014-09-19 10:00:15 +0000.

As specified in instantiation of custom elements that "custom tag" will take preference over "type extension", it is required to specify the same in case of createElement(...) .

 Element createElement(DOMString localName, DOMString typeExtension);

Here if localName is also a custom tag, then what will be the prototype of "Element"? Will it be of typeExtension or of localName.

Consider the following case:

var xA = doc.registerElement("x-a");
var xB = doc.registerElement("x-b");

var customElement = doc.createElement("x-a", "x-b");

What should be the prototype of customElement?

AFAIK, this will be the same case as specifying:

\<x-a is="x-b">\</x-a\>

In this case prototype will be of "x-a".

If the above theory is correct, then web-platform-tests/custom-elements/instantiating-custom-elements/extensions-to-document-interface/create-element-interface-type-is-a-type-extension.html test case is wrong.

If this issue has been raised earlier, then please provide the link and close this bug.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/167