luhn-generator/update/node_modules/axe-core/lib/commons/dom/is-focusable.js

A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

import focusDisabled from './focus-disabled';
import isNativelyFocusable from './is-natively-focusable';
import AbstractVirtualNode from '../../core/base/virtual-node/abstract-virtual-node';
import { getNodeFromTree } from '../../core/utils';

/**
 * Determines if an element is focusable
 * @method isFocusable
 * @memberof axe.commons.dom
 * @instance
 * @param {HTMLElement} el The HTMLElement
 * @return {Boolean} The element's focusability status
 */

function isFocusable(el) {
	const vNode = el instanceof AbstractVirtualNode ? el : getNodeFromTree(el);

	if (focusDisabled(vNode)) {
		return false;
	} else if (isNativelyFocusable(vNode)) {
		return true;
	}
	// check if the tabindex is specified and a parseable number
	var tabindex = vNode.attr('tabindex');
	if (tabindex && !isNaN(parseInt(tabindex, 10))) {
		return true;
	}

	return false;
}

export default isFocusable;