Add helpers file

src/_data/helpers.js

@@ -0,0 +1,23 @@
+module.exports = {
+    /**
+     * Returns back some attributes based on wether the
+     * link is active or a parent of an active item
+     *
+     * @param {String} itemUrl The link in question
+     * @param {String} pageUrl The page context
+     * @returns {String} The attributes or empty
+     */
+    getLinkActiveState(itemUrl, pageUrl) {
+      let response = '';
+  
+      if (itemUrl === pageUrl) {
+        response = ' aria-current="page"';
+      }
+  
+      if (itemUrl.length > 1 && pageUrl.indexOf(itemUrl) === 0) {
+        response += ' data-state="active"';
+      }
+  
+      return response;
+    },
+};