John Cowen 25f3ebd66a
ui: CustomElement component (#12451)
Builds on attach-shadow, adopt-styles and ShadowTemplate, this commit adds ShadowHost and finally CustomElement.

CustomElement is a renderless component to help with the creation of native HTML Custom Elements along with runtime type checking and self-documentation for attributes, slots, cssprops and cssparts. As you will probably see there is a little more work to come here. But in the same breath, everything would be fine to go in as is.
2022-03-07 09:51:47 +00:00

19 lines
643 B
JavaScript

import { helper } from '@ember/component/helper';
/**
* Conditionally maps classInfos (classes) to a string ready for typical DOM
* usage (i.e. space delimited)
*
* @typedef {([string, boolean] | [string])} classInfo
* @param {(classInfo | string)[]} entries - An array of 'entry-like' arrays of `classInfo`s to map
*/
const classMap = entries => {
const str = entries
.filter(Boolean)
.filter(entry => (typeof entry === 'string' ? true : entry[entry.length - 1]))
.map(entry => (typeof entry === 'string' ? entry : entry[0]))
.join(' ');
return str.length > 0 ? str : undefined;
};
export default helper(classMap);