Prefer const/let over var

core/util/browser.js

@@ -9,7 +9,7 @@
 import * as Log from './logging.js';
 
 // Touch detection
-export var isTouchDevice = ('ontouchstart' in document.documentElement) ||
+export let isTouchDevice = ('ontouchstart' in document.documentElement) ||
                                  // requried for Chrome debugger
                                  (document.ontouchstart !== undefined) ||
                                  // required for MS Surface
@@ -20,12 +20,12 @@ window.addEventListener('touchstart', function onFirstTouch() {
     window.removeEventListener('touchstart', onFirstTouch, false);
 }, false);
 
-var _cursor_uris_supported = null;
+let _cursor_uris_supported = null;
 
 export function supportsCursorURIs () {
     if (_cursor_uris_supported === null) {
         try {
-            var target = document.createElement('canvas');
+            const target = document.createElement('canvas');
             target.style.cursor = 'url("data:image/x-icon;base64,AAACAAEACAgAAAIAAgA4AQAAFgAAACgAAAAIAAAAEAAAAAEAIAAAAAAAEAAAAAAAAAAAAAAAAAAAAAAAAAD/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////AAAAAAAAAAAAAAAAAAAAAA==") 2 2, default';
 
             if (target.style.cursor) {

core/util/events.js

@@ -20,14 +20,14 @@ export function stopEvent (e) {
 }
 
 // Emulate Element.setCapture() when not supported
-var _captureRecursion = false;
-var _captureElem = null;
+let _captureRecursion = false;
+let _captureElem = null;
 function _captureProxy(e) {
     // Recursion protection as we'll see our own event
     if (_captureRecursion) return;
 
     // Clone the event as we cannot dispatch an already dispatched event
-    var newEv = new e.constructor(e.type, e);
+    const newEv = new e.constructor(e.type, e);
 
     _captureRecursion = true;
     _captureElem.dispatchEvent(newEv);
@@ -49,12 +49,13 @@ function _captureProxy(e) {
 
 // Follow cursor style of target element
 function _captureElemChanged() {
-    var captureElem = document.getElementById("noVNC_mouse_capture_elem");
+    const captureElem = document.getElementById("noVNC_mouse_capture_elem");
     captureElem.style.cursor = window.getComputedStyle(_captureElem).cursor;
 }
-var _captureObserver = new MutationObserver(_captureElemChanged);
 
-var _captureIndex = 0;
+const _captureObserver = new MutationObserver(_captureElemChanged);
+
+let _captureIndex = 0;
 
 export function setCapture (elem) {
     if (elem.setCapture) {
@@ -69,7 +70,7 @@ export function setCapture (elem) {
         // called multiple times without coordination
         releaseCapture();
 
-        var captureElem = document.getElementById("noVNC_mouse_capture_elem");
+        let captureElem = document.getElementById("noVNC_mouse_capture_elem");
 
         if (captureElem === null) {
             captureElem = document.createElement("div");
@@ -129,7 +130,7 @@ export function releaseCapture () {
 
         _captureObserver.disconnect();
 
-        var captureElem = document.getElementById("noVNC_mouse_capture_elem");
+        const captureElem = document.getElementById("noVNC_mouse_capture_elem");
         captureElem.style.display = "none";
 
         window.removeEventListener('mousemove', _captureProxy);

core/util/eventtarget.js

@@ -6,7 +6,7 @@
  * See README.md for usage and integration instructions.
  */
 
-var EventTargetMixin = {
+const EventTargetMixin = {
     _listeners: null,
 
    addEventListener: function(type, callback) {

core/util/logging.js

@@ -10,12 +10,12 @@
  * Logging/debug routines
  */
 
-var _log_level = 'warn';
+let _log_level = 'warn';
 
-var Debug = function (msg) {};
-var Info = function (msg) {};
-var Warn = function (msg) {};
-var Error = function (msg) {};
+let Debug = function (msg) {};
+let Info = function (msg) {};
+let Warn = function (msg) {};
+let Error = function (msg) {};
 
 export function init_logging (level) {
     if (typeof level === 'undefined') {

core/util/polyfill.js

@@ -16,13 +16,13 @@ if (typeof Object.assign != 'function') {
                 throw new TypeError('Cannot convert undefined or null to object');
             }
 
-            var to = Object(target);
+            const to = Object(target);
 
-            for (var index = 1; index < arguments.length; index++) {
-                var nextSource = arguments[index];
+            for (let index = 1; index < arguments.length; index++) {
+                const nextSource = arguments[index];
 
                 if (nextSource != null) { // Skip over if undefined or null
-                    for (var nextKey in nextSource) {
+                    for (let nextKey in nextSource) {
                         // Avoid bugs when hasOwnProperty is shadowed
                         if (Object.prototype.hasOwnProperty.call(nextSource, nextKey)) {
                             to[nextKey] = nextSource[nextKey];
@@ -41,7 +41,7 @@ if (typeof Object.assign != 'function') {
 (function () {
     function CustomEvent ( event, params ) {
         params = params || { bubbles: false, cancelable: false, detail: undefined };
-        var evt = document.createEvent( 'CustomEvent' );
+        const evt = document.createEvent( 'CustomEvent' );
         evt.initCustomEvent( event, params.bubbles, params.cancelable, params.detail );
         return evt;
     }