chore: modernize aria-required-children check file

lib/checks/aria/required-children.js

@@ -10,8 +10,8 @@ function owns(node, virtualTree, role, ariaOwned) {
 	if (node === null) {
 		return false;
 	}
-	var implicit = implicitNodes(role),
-		selector = ['[role="' + role + '"]'];
+	const implicit = implicitNodes(role);
+	let selector = ['[role="' + role + '"]'];
 
 	if (implicit) {
 		selector = selector.concat(
@@ -27,28 +27,23 @@ function owns(node, virtualTree, role, ariaOwned) {
 }
 
 function ariaOwns(nodes, role) {
-	var index, length;
-
-	for (index = 0, length = nodes.length; index < length; index++) {
-		if (nodes[index] === null) {
+	for (const node of nodes) {
+		if (node === null) {
 			continue;
 		}
-		const virtualTree = axe.utils.getNodeFromTree(nodes[index]);
-		if (owns(nodes[index], virtualTree, role, true)) {
+		const virtualTree = axe.utils.getNodeFromTree(node);
+		if (owns(node, virtualTree, role, true)) {
 			return true;
 		}
 	}
 	return false;
 }
 
 function missingRequiredChildren(node, childRoles, all, role) {
-	var index,
-		length = childRoles.length,
-		missing = [],
+	const missing = [],
 		ownedElements = idrefs(node, 'aria-owns');
 
-	for (index = 0; index < length; index++) {
-		var childRole = childRoles[index];
+	for (const childRole of childRoles) {
 		if (
 			owns(node, virtualNode, childRole) ||
 			ariaOwns(ownedElements, childRole)
@@ -66,8 +61,8 @@ function missingRequiredChildren(node, childRoles, all, role) {
 	// combobox exceptions
 	if (role === 'combobox') {
 		// remove 'textbox' from missing roles if combobox is a native text-type input or owns a 'searchbox'
-		var textboxIndex = missing.indexOf('textbox');
-		var textTypeInputs = ['text', 'search', 'email', 'url', 'tel'];
+		const textboxIndex = missing.indexOf('textbox');
+		const textTypeInputs = ['text', 'search', 'email', 'url', 'tel'];
 		if (
 			(textboxIndex >= 0 &&
 				(node.nodeName.toUpperCase() === 'INPUT' &&
@@ -119,21 +114,21 @@ function hasDecendantWithRole(node) {
 	);
 }
 
-var role = node.getAttribute('role');
-var required = requiredOwned(role);
+const role = node.getAttribute('role');
+const required = requiredOwned(role);
 
 if (!required) {
 	return true;
 }
 
-var all = false;
-var childRoles = required.one;
+let all = false;
+let childRoles = required.one;
 if (!childRoles) {
-	var all = true;
+	all = true;
 	childRoles = required.all;
 }
 
-var missing = missingRequiredChildren(node, childRoles, all, role);
+const missing = missingRequiredChildren(node, childRoles, all, role);
 
 if (!missing) {
 	return true;