Migrate AutoFocuser to ES6

package.json

@@ -73,6 +73,7 @@
     "presets": ["@babel/preset-env"],
     "overrides": [{
         "test": [
+            "src/components/autoFocuser.js",
             "src/components/cardbuilder/cardBuilder.js",
             "src/components/filedownloader.js",
             "src/components/filesystem.js",

src/components/autoFocuser.js

@@ -1,22 +1,29 @@
-define(["focusManager", "layoutManager"], function (focusManager, layoutManager) {
+/* eslint-disable indent */
-    "use strict";
+
+/**
+ * Module for performing auto-focus.
+ * @module components/autoFocuser
+ */
+
+import focusManager from "focusManager";
+import layoutManager from "layoutManager";
 
     /**
      * Previously selected element.
      */
-    var activeElement;
+    let activeElement;
 
     /**
-     * Returns true if AutoFocuser is enabled.
+     * Returns _true_ if AutoFocuser is enabled.
      */
-    function isEnabled() {
+    export function isEnabled() {
         return layoutManager.tv;
     }
 
     /**
      * Start AutoFocuser
      */
-    function enable() {
+    export function enable() {
         if (!isEnabled()) {
             return;
         }
@@ -28,24 +35,19 @@ define(["focusManager", "layoutManager"], function (focusManager, layoutManager)
         console.debug("AutoFocuser enabled");
     }
 
-    /**
-     * Create an array from some source.
-     */
-    var arrayFrom = Array.prototype.from || function (src) {
-        return Array.prototype.slice.call(src);
-    }
-
     /**
      * Set focus on a suitable element, taking into account the previously selected.
+     * @param {HTMLElement} [container] - element to limit scope
+     * @returns {HTMLElement} focused element
      */
-    function autoFocus(container) {
+    export function autoFocus(container) {
         if (!isEnabled()) {
-            return;
+            return null;
         }
 
         container = container || document.body;
 
-        var candidates = [];
+        let candidates = [];
 
         if (activeElement) {
             // These elements are recreated
@@ -62,10 +64,10 @@ define(["focusManager", "layoutManager"], function (focusManager, layoutManager)
             candidates.push(activeElement);
         }
 
-        candidates = candidates.concat(arrayFrom(container.querySelectorAll(".btnResume")));
+        candidates = candidates.concat(Array.from(container.querySelectorAll(".btnResume")));
-        candidates = candidates.concat(arrayFrom(container.querySelectorAll(".btnPlay")));
+        candidates = candidates.concat(Array.from(container.querySelectorAll(".btnPlay")));
 
-        var focusedElement;
+        let focusedElement;
 
         candidates.every(function (element) {
             if (focusManager.isCurrentlyFocusable(element)) {
@@ -79,7 +81,7 @@ define(["focusManager", "layoutManager"], function (focusManager, layoutManager)
 
         if (!focusedElement) {
             // FIXME: Multiple itemsContainers
-            var itemsContainer = container.querySelector(".itemsContainer");
+            const itemsContainer = container.querySelector(".itemsContainer");
 
             if (itemsContainer) {
                 focusedElement = focusManager.autoFocus(itemsContainer);
@@ -93,9 +95,8 @@ define(["focusManager", "layoutManager"], function (focusManager, layoutManager)
         return focusedElement;
     }
 
-    return {
+    export default {
         isEnabled: isEnabled,
         enable: enable,
         autoFocus: autoFocus
     };
-});