refactor: replace var with const / let (electron#14866)

.eslintrc

@@ -2,5 +2,8 @@
   "extends": "standard",
   "env": {
     "browser": true
+  },
+  "rules": {
+    "no-var": "error"
   }
 }

lib/browser/api/auto-updater/squirrel-update-win.js

@@ -86,13 +86,13 @@ exports.processStart = function () {
 // Download the releases specified by the URL and write new results to stdout.
 exports.checkForUpdate = function (updateURL, callback) {
   return spawnUpdate(['--checkForUpdate', updateURL], false, function (error, stdout) {
-    var json, ref, ref1, update
+    let ref, ref1, update
     if (error != null) {
       return callback(error)
     }
     try {
       // Last line of output is the JSON details about the releases
-      json = stdout.trim().split('\n').pop()
+      const json = stdout.trim().split('\n').pop()
       update = (ref = JSON.parse(json)) != null ? (ref1 = ref.releasesToApply) != null ? typeof ref1.pop === 'function' ? ref1.pop() : void 0 : void 0 : void 0
     } catch (jsonError) {
       // Disabled for backwards compatibility:

lib/browser/api/navigation-controller.js

@@ -16,7 +16,7 @@ ipcMain.on('ELECTRON_SYNC_NAVIGATION_CONTROLLER', function (event, method, ...ar
 // control on user land, and only rely on WebContents.loadURL for navigation.
 // This helps us avoid Chromium's various optimizations so we can ensure renderer
 // process is restarted everytime.
-var NavigationController = (function () {
+const NavigationController = (function () {
   function NavigationController (webContents) {
     this.webContents = webContents
     this.clearHistory()
@@ -141,7 +141,7 @@ var NavigationController = (function () {
   }
 
   NavigationController.prototype.goToOffset = function (offset) {
-    var pendingIndex
+    let pendingIndex
     if (!this.canGoToOffset(offset)) {
       return
     }

lib/browser/init.js

@@ -7,7 +7,7 @@ const util = require('util')
 const Module = require('module')
 const v8 = require('v8')
 
-// We modified the original process.argv to let node.js load the atom.js,
+// We modified the original process.argv to let node.js load the init.js,
 // we need to restore it here.
 process.argv.splice(1, 1)
 
@@ -17,18 +17,18 @@ require('../common/reset-search-paths')
 // Import common settings.
 require('@electron/internal/common/init')
 
-var globalPaths = Module.globalPaths
+const globalPaths = Module.globalPaths
 
 // Expose public APIs.
 globalPaths.push(path.join(__dirname, 'api', 'exports'))
 
 if (process.platform === 'win32') {
   // Redirect node's console to use our own implementations, since node can not
   // handle console output when running as GUI program.
-  var consoleLog = function (...args) {
+  const consoleLog = function (...args) {
     return process.log(util.format(...args) + '\n')
   }
-  var streamWrite = function (chunk, encoding, callback) {
+  const streamWrite = function (chunk, encoding, callback) {
     if (Buffer.isBuffer(chunk)) {
       chunk = chunk.toString(encoding)
     }
@@ -45,15 +45,14 @@ if (process.platform === 'win32') {
 // Don't quit on fatal error.
 process.on('uncaughtException', function (error) {
   // Do nothing if the user has a custom uncaught exception handler.
-  var dialog, message, ref, stack
   if (process.listeners('uncaughtException').length > 1) {
     return
   }
 
   // Show error in GUI.
-  dialog = require('electron').dialog
-  stack = (ref = error.stack) != null ? ref : error.name + ': ' + error.message
-  message = 'Uncaught Exception:\n' + stack
+  const dialog = require('electron').dialog
+  const stack = error.stack ? error.stack : `${error.name}: ${error.message}`
+  const message = 'Uncaught Exception:\n' + stack
   dialog.showErrorBox('A JavaScript error occurred in the main process', message)
 })
 

lib/common/init.js

@@ -31,7 +31,6 @@ function wrap (func, wrapper) {
 process.nextTick = wrapWithActivateUvLoop(process.nextTick)
 
 global.setImmediate = wrapWithActivateUvLoop(timers.setImmediate)
-
 global.clearImmediate = timers.clearImmediate
 
 if (process.type === 'browser') {

lib/renderer/extensions/storage.js

@@ -93,7 +93,7 @@ const getStorageManager = (storageType, extensionId) => {
 
         let items = {}
         keys.forEach(function (key) {
-          var value = storage[key]
+          let value = storage[key]
           if (value == null) value = defaults[key]
           items[key] = value
         })

lib/renderer/init.js

@@ -14,13 +14,13 @@ require('../common/reset-search-paths')
 // Import common settings.
 require('@electron/internal/common/init')
 
-var globalPaths = Module.globalPaths
+const globalPaths = Module.globalPaths
 
 // Expose public APIs.
 globalPaths.push(path.join(__dirname, 'api', 'exports'))
 
 // The global variable will be used by ipc for event dispatching
-var v8Util = process.atomBinding('v8_util')
+const v8Util = process.atomBinding('v8_util')
 
 v8Util.setHiddenValue(global, 'ipc', new events.EventEmitter())
 

script/lib/tls/index.js

@@ -1,8 +1,8 @@
-var fs = require('fs')
-var https = require('https')
-var path = require('path')
+const fs = require('fs')
+const https = require('https')
+const path = require('path')
 
-var server = https.createServer({
+const server = https.createServer({
   key: fs.readFileSync(path.resolve(__dirname, 'tls.key.pem')),
   cert: fs.readFileSync(path.resolve(__dirname, 'tls.cert.pem'))
 }, (req, res) => {

script/start.js

@@ -4,7 +4,7 @@ const utils = require('./lib/utils')
 
 const electronPath = utils.getAbsoluteElectronExec()
 
-var child = cp.spawn(electronPath, process.argv.slice(2), { stdio: 'inherit' })
+const child = cp.spawn(electronPath, process.argv.slice(2), { stdio: 'inherit' })
 child.on('close', (code) => process.exit(code))
 
 const handleTerminationSignal = (signal) =>

spec/api-browser-window-spec.js

@@ -581,7 +581,7 @@ describe('BrowserWindow module', () => {
     it('sets the content size', () => {
       const size = [400, 400]
       w.setContentSize(size[0], size[1])
-      var after = w.getContentSize()
+      const after = w.getContentSize()
       assert.strictEqual(after[0], size[0])
       assert.strictEqual(after[1], size[1])
     })
@@ -3132,7 +3132,7 @@ describe('BrowserWindow module', () => {
         }
       })
 
-      var extensionPath = path.join(__dirname, 'fixtures', 'devtools-extensions', 'foo')
+      const extensionPath = path.join(__dirname, 'fixtures', 'devtools-extensions', 'foo')
       BrowserWindow.removeDevToolsExtension('foo')
       BrowserWindow.addDevToolsExtension(extensionPath)
 
@@ -3148,9 +3148,9 @@ describe('BrowserWindow module', () => {
     })
 
     it('serializes the registered extensions on quit', () => {
-      var extensionName = 'foo'
-      var extensionPath = path.join(__dirname, 'fixtures', 'devtools-extensions', extensionName)
-      var serializedPath = path.join(app.getPath('userData'), 'DevTools Extensions')
+      const extensionName = 'foo'
+      const extensionPath = path.join(__dirname, 'fixtures', 'devtools-extensions', extensionName)
+      const serializedPath = path.join(app.getPath('userData'), 'DevTools Extensions')
 
       BrowserWindow.addDevToolsExtension(extensionPath)
       app.emit('will-quit')
@@ -3166,7 +3166,7 @@ describe('BrowserWindow module', () => {
         BrowserWindow.removeExtension('foo')
         assert.strictEqual(BrowserWindow.getExtensions().hasOwnProperty('foo'), false)
 
-        var extensionPath = path.join(__dirname, 'fixtures', 'devtools-extensions', 'foo')
+        const extensionPath = path.join(__dirname, 'fixtures', 'devtools-extensions', 'foo')
         BrowserWindow.addExtension(extensionPath)
         assert.strictEqual(BrowserWindow.getExtensions().hasOwnProperty('foo'), true)
 

spec/api-protocol-spec.js

@@ -663,7 +663,7 @@ describe('protocol module', () => {
     })
 
     it('does not crash when handler is called twice', (done) => {
-      var doubleHandler = (request, callback) => {
+      const doubleHandler = (request, callback) => {
         try {
           callback(text)
           callback()

spec/api-web-frame-spec.js

@@ -14,16 +14,16 @@ chai.use(dirtyChai)
 /* eslint-disable standard/no-callback-literal */
 
 describe('webFrame module', function () {
-  var fixtures = path.resolve(__dirname, 'fixtures')
-  var w = null
+  const fixtures = path.resolve(__dirname, 'fixtures')
+  let w = null
 
   afterEach(function () {
     return closeWindow(w).then(function () { w = null })
   })
 
   describe('webFrame.registerURLSchemeAsPrivileged', function () {
     it('supports fetch api by default', function (done) {
-      var url = 'file://' + fixtures + '/assets/logo.png'
+      const url = 'file://' + fixtures + '/assets/logo.png'
       window.fetch(url).then(function (response) {
         assert(response.ok)
         done()
@@ -102,7 +102,7 @@ describe('webFrame module', function () {
       </html>`, done)
     })
 
-    var runNumber = 1
+    let runNumber = 1
     function allowsCORSRequests (expected, content, done) {
       const standardScheme = remote.getGlobal('standardScheme') + runNumber
       const corsScheme = 'cors' + runNumber