diff --git a/lib/browser/api/menu.js b/lib/browser/api/menu.js
index 174acd7d9199..caa65afbbf0a 100644
--- a/lib/browser/api/menu.js
+++ b/lib/browser/api/menu.js
@@ -5,139 +5,39 @@ const EventEmitter = require('events').EventEmitter
 const v8Util = process.atomBinding('v8_util')
 const bindings = process.atomBinding('menu')
 
-// Automatically generated radio menu item's group id.
-var nextGroupId = 0
-
-// Search between separators to find a radio menu item and return its group id,
-// otherwise generate a group id.
-var generateGroupId = function (items, pos) {
-  var i, item, j, k, ref1, ref2, ref3
-  if (pos > 0) {
-    for (i = j = ref1 = pos - 1; ref1 <= 0 ? j <= 0 : j >= 0; i = ref1 <= 0 ? ++j : --j) {
-      item = items[i]
-      if (item.type === 'radio') {
-        return item.groupId
-      }
-      if (item.type === 'separator') {
-        break
-      }
-    }
-  } else if (pos < items.length) {
-    for (i = k = ref2 = pos, ref3 = items.length - 1; ref2 <= ref3 ? k <= ref3 : k >= ref3; i = ref2 <= ref3 ? ++k : --k) {
-      item = items[i]
-      if (item.type === 'radio') {
-        return item.groupId
-      }
-      if (item.type === 'separator') {
-        break
-      }
-    }
-  }
-  return ++nextGroupId
-}
-
-// Returns the index of item according to |id|.
-var indexOfItemById = function (items, id) {
-  var i, item, j, len
-  for (i = j = 0, len = items.length; j < len; i = ++j) {
-    item = items[i]
-    if (item.id === id) {
-      return i
-    }
-  }
-  return -1
-}
-
-// Returns the index of where to insert the item according to |position|.
-var indexToInsertByPosition = function (items, position) {
-  var insertIndex
-  if (!position) {
-    return items.length
-  }
-  const [query, id] = position.split('=')
-  insertIndex = indexOfItemById(items, id)
-  if (insertIndex === -1 && query !== 'endof') {
-    console.warn("Item with id '" + id + "' is not found")
-    return items.length
-  }
-  switch (query) {
-    case 'after':
-      insertIndex++
-      break
-    case 'endof':
-
-      // If the |id| doesn't exist, then create a new group with the |id|.
-      if (insertIndex === -1) {
-        items.push({
-          id: id,
-          type: 'separator'
-        })
-        insertIndex = items.length - 1
-      }
-
-      // Find the end of the group.
-      insertIndex++
-      while (insertIndex < items.length && items[insertIndex].type !== 'separator') {
-        insertIndex++
-      }
-  }
-  return insertIndex
-}
-
-const Menu = bindings.Menu
+const {Menu} = bindings
+let applicationMenu = null
+let groupIdIndex = 0
 
 Object.setPrototypeOf(Menu.prototype, EventEmitter.prototype)
 
+/* Instance Methods */
+
 Menu.prototype._init = function () {
   this.commandsMap = {}
   this.groupsMap = {}
   this.items = []
   this.delegate = {
-    isCommandIdChecked: (commandId) => {
-      var command = this.commandsMap[commandId]
-      return command != null ? command.checked : undefined
-    },
-    isCommandIdEnabled: (commandId) => {
-      var command = this.commandsMap[commandId]
-      return command != null ? command.enabled : undefined
-    },
-    isCommandIdVisible: (commandId) => {
-      var command = this.commandsMap[commandId]
-      return command != null ? command.visible : undefined
-    },
-    getAcceleratorForCommandId: (commandId, useDefaultAccelerator) => {
-      const command = this.commandsMap[commandId]
-      if (command == null) return
-      if (command.accelerator != null) return command.accelerator
+    isCommandIdChecked: id => this.commandsMap[id] ? this.commandsMap[id].checked : undefined,
+    isCommandIdEnabled: id => this.commandsMap[id] ? this.commandsMap[id].enabled : undefined,
+    isCommandIdVisible: id => this.commandsMap[id] ? this.commandsMap[id].visible : undefined,
+    getAcceleratorForCommandId: (id, useDefaultAccelerator) => {
+      const command = this.commandsMap[id]
+      if (!command) return
+      if (command.accelerator) return command.accelerator
       if (useDefaultAccelerator) return command.getDefaultRoleAccelerator()
     },
-    getIconForCommandId: (commandId) => {
-      var command = this.commandsMap[commandId]
-      return command != null ? command.icon : undefined
-    },
-    executeCommand: (event, commandId) => {
-      const command = this.commandsMap[commandId]
-      if (command == null) return
+    getIconForCommandId: id => this.commandsMap[id] ? this.commandsMap[id].icon : undefined,
+    executeCommand: (event, id) => {
+      const command = this.commandsMap[id]
+      if (!command) return
       command.click(event, BrowserWindow.getFocusedWindow(), webContents.getFocusedWebContents())
     },
     menuWillShow: () => {
-      // Make sure radio groups have at least one menu item seleted.
-      var checked, group, id, j, len, radioItem, ref1
-      ref1 = this.groupsMap
-      for (id in ref1) {
-        group = ref1[id]
-        checked = false
-        for (j = 0, len = group.length; j < len; j++) {
-          radioItem = group[j]
-          if (!radioItem.checked) {
-            continue
-          }
-          checked = true
-          break
-        }
-        if (!checked) {
-          v8Util.setHiddenValue(group[0], 'checked', true)
-        }
+      // Ensure radio groups have at least one menu item seleted
+      for (const id in this.groupsMap) {
+        const found = this.groupsMap[id].find(item => item.checked) || null
+        if (!found) v8Util.setHiddenValue(this.groupsMap[id][0], 'checked', true)
       }
     }
   }
@@ -145,55 +45,47 @@ Menu.prototype._init = function () {
 
 Menu.prototype.popup = function (window, x, y, positioningItem) {
   let asyncPopup
+  let [newX, newY, newPosition, newWindow] = [x, y, positioningItem, window]
 
   // menu.popup(x, y, positioningItem)
-  if (window != null && (typeof window !== 'object' || window.constructor !== BrowserWindow)) {
-    // Shift.
-    positioningItem = y
-    y = x
-    x = window
-    window = null
+  if (!window) {
+    // shift over values
+    if (typeof window !== 'object' || window.constructor !== BrowserWindow) {
+      [newPosition, newY, newX, newWindow] = [y, x, window, null]
+    }
   }
 
   // menu.popup(window, {})
-  if (x != null && typeof x === 'object') {
-    const options = x
-    x = options.x
-    y = options.y
-    positioningItem = options.positioningItem
-    asyncPopup = options.async
+  if (x && typeof x === 'object') {
+    const opts = x
+    newX = opts.x
+    newY = opts.y
+    newPosition = opts.positioningItem
+    asyncPopup = opts.async
   }
 
-  // Default to showing in focused window.
-  if (window == null) window = BrowserWindow.getFocusedWindow()
-
-  // Default to showing under mouse location.
-  if (typeof x !== 'number') x = -1
-  if (typeof y !== 'number') y = -1
-
-  // Default to not highlighting any item.
-  if (typeof positioningItem !== 'number') positioningItem = -1
-
-  // Default to synchronous for backwards compatibility.
+  // set defaults
+  if (typeof x !== 'number') newX = -1
+  if (typeof y !== 'number') newY = -1
+  if (typeof positioningItem !== 'number') newPosition = -1
+  if (!window) newWindow = BrowserWindow.getFocusedWindow()
   if (typeof asyncPopup !== 'boolean') asyncPopup = false
 
-  this.popupAt(window, x, y, positioningItem, asyncPopup)
+  this.popupAt(newWindow, newX, newY, newPosition, asyncPopup)
 }
 
 Menu.prototype.closePopup = function (window) {
-  if (window == null || window.constructor !== BrowserWindow) {
+  if (!window || window.constructor !== BrowserWindow) {
     window = BrowserWindow.getFocusedWindow()
   }
-  if (window != null) {
-    this.closePopupAt(window.id)
-  }
+  if (window) this.closePopupAt(window.id)
 }
 
 Menu.prototype.getMenuItemById = function (id) {
   const items = this.items
 
   let found = items.find(item => item.id === id) || null
-  for (let i = 0, length = items.length; !found && i < length; i++) {
+  for (let i = 0; !found && i < items.length; i++) {
     if (items[i].submenu) {
       found = items[i].submenu.getMenuItemById(id)
     }
@@ -206,61 +98,17 @@ Menu.prototype.append = function (item) {
 }
 
 Menu.prototype.insert = function (pos, item) {
-  var base, name
-  if ((item != null ? item.constructor : void 0) !== MenuItem) {
+  if ((item ? item.constructor : void 0) !== MenuItem) {
     throw new TypeError('Invalid item')
   }
-  switch (item.type) {
-    case 'normal':
-      this.insertItem(pos, item.commandId, item.label)
-      break
-    case 'checkbox':
-      this.insertCheckItem(pos, item.commandId, item.label)
-      break
-    case 'separator':
-      this.insertSeparator(pos)
-      break
-    case 'submenu':
-      this.insertSubMenu(pos, item.commandId, item.label, item.submenu)
-      break
-    case 'radio':
-      // Grouping radio menu items.
-      item.overrideReadOnlyProperty('groupId', generateGroupId(this.items, pos))
-      if ((base = this.groupsMap)[name = item.groupId] == null) {
-        base[name] = []
-      }
-      this.groupsMap[item.groupId].push(item)
 
-      // Setting a radio menu item should flip other items in the group.
-      v8Util.setHiddenValue(item, 'checked', item.checked)
-      Object.defineProperty(item, 'checked', {
-        enumerable: true,
-        get: function () {
-          return v8Util.getHiddenValue(item, 'checked')
-        },
-        set: () => {
-          var j, len, otherItem, ref1
-          ref1 = this.groupsMap[item.groupId]
-          for (j = 0, len = ref1.length; j < len; j++) {
-            otherItem = ref1[j]
-            if (otherItem !== item) {
-              v8Util.setHiddenValue(otherItem, 'checked', false)
-            }
-          }
-          return v8Util.setHiddenValue(item, 'checked', true)
-        }
-      })
-      this.insertRadioItem(pos, item.commandId, item.label, item.groupId)
-  }
-  if (item.sublabel != null) {
-    this.setSublabel(pos, item.sublabel)
-  }
-  if (item.icon != null) {
-    this.setIcon(pos, item.icon)
-  }
-  if (item.role != null) {
-    this.setRole(pos, item.role)
-  }
+  // insert item depending on its type
+  insertItemByType.call(this, item, pos)
+
+  // set item properties
+  if (item.sublabel) this.setSublabel(pos, item.sublabel)
+  if (item.icon) this.setIcon(pos, item.icon)
+  if (item.role) this.setRole(pos, item.role)
 
   // Make menu accessable to items.
   item.overrideReadOnlyProperty('menu', this)
@@ -270,73 +118,150 @@ Menu.prototype.insert = function (pos, item) {
   this.commandsMap[item.commandId] = item
 }
 
-// Force menuWillShow to be called
 Menu.prototype._callMenuWillShow = function () {
-  if (this.delegate != null) {
-    this.delegate.menuWillShow()
-  }
-  this.items.forEach(function (item) {
-    if (item.submenu != null) {
-      item.submenu._callMenuWillShow()
-    }
+  if (this.delegate) this.delegate.menuWillShow()
+  this.items.forEach(item => {
+    if (item.submenu) item.submenu._callMenuWillShow()
   })
 }
 
-var applicationMenu = null
+/* Static Methods */
 
-Menu.setApplicationMenu = function (menu) {
-  if (!(menu === null || menu.constructor === Menu)) {
-    throw new TypeError('Invalid menu')
-  }
-
-  // Keep a reference.
-  applicationMenu = menu
-  if (process.platform === 'darwin') {
-    if (menu === null) {
-      return
-    }
-    menu._callMenuWillShow()
-    bindings.setApplicationMenu(menu)
-  } else {
-    BrowserWindow.getAllWindows().forEach(function (window) {
-      window.setMenu(menu)
-    })
-  }
-}
-
-Menu.getApplicationMenu = function () {
-  return applicationMenu
-}
+Menu.getApplicationMenu = () => applicationMenu
 
 Menu.sendActionToFirstResponder = bindings.sendActionToFirstResponder
 
+// set application menu with a preexisting menu
+Menu.setApplicationMenu = function (menu) {
+  if (!(menu || menu.constructor === Menu)) {
+    throw new TypeError('Invalid menu')
+  }
+
+  applicationMenu = menu
+  if (process.platform === 'darwin') {
+    if (!menu) return
+    menu._callMenuWillShow()
+    bindings.setApplicationMenu(menu)
+  } else {
+    const windows = BrowserWindow.getAllWindows()
+    return windows.map(w => w.setMenu(menu))
+  }
+}
+
 Menu.buildFromTemplate = function (template) {
-  var insertIndex, item, j, k, len, len1, menu, menuItem, positionedTemplate
-  if (!Array.isArray(template)) {
+  if (!(template instanceof Array)) {
     throw new TypeError('Invalid template for Menu')
   }
-  positionedTemplate = []
-  insertIndex = 0
-  for (j = 0, len = template.length; j < len; j++) {
-    item = template[j]
-    if (item.position) {
-      insertIndex = indexToInsertByPosition(positionedTemplate, item.position)
-    } else {
-      // If no |position| is specified, insert after last item.
-      insertIndex++
-    }
-    positionedTemplate.splice(insertIndex, 0, item)
-  }
-  menu = new Menu()
-  for (k = 0, len1 = positionedTemplate.length; k < len1; k++) {
-    item = positionedTemplate[k]
+
+  const menu = new Menu()
+  const positioned = []
+  let idx = 0
+
+  // sort template by position
+  template.forEach(item => {
+    idx = (item.position) ? indexToInsertByPosition(positioned, item.position) : idx += 1
+    positioned.splice(idx, 0, item)
+  })
+
+  // add each item from positioned menu to application menu
+  positioned.forEach((item) => {
     if (typeof item !== 'object') {
       throw new TypeError('Invalid template for MenuItem')
     }
-    menuItem = new MenuItem(item)
-    menu.append(menuItem)
-  }
+    menu.append(new MenuItem(item))
+  })
+
   return menu
 }
 
+/* Helper Functions */
+
+// Search between separators to find a radio menu item and return its group id
+function generateGroupId (items, pos) {
+  if (pos > 0) {
+    for (let idx = pos - 1; idx >= 0; idx--) {
+      if (items[idx].type === 'radio') return items[idx].groupId
+      if (items[idx].type === 'separator') break
+    }
+  } else if (pos < items.length) {
+    for (let idx = pos; idx <= items.length - 1; idx++) {
+      if (items[idx].type === 'radio') return items[idx].groupId
+      if (items[idx].type === 'separator') break
+    }
+  }
+  groupIdIndex += 1
+  return groupIdIndex
+}
+
+function indexOfItemById (items, id) {
+  const foundItem = items.find(item => item.id === id) || -1
+  return items.indexOf(foundItem)
+}
+
+function indexToInsertByPosition (items, position) {
+  if (!position) return items.length
+
+  const [query, id] = position.split('=') // parse query and id from position
+  const idx = indexOfItemById(items, id) // calculate initial index of item
+
+  // warn if query doesn't exist
+  if (idx === -1 && query !== 'endof') {
+    console.warn(`Item with id ${id} is not found`)
+    return items.length
+  }
+
+  // compute new index based on query
+  const queries = {
+    after: (index) => {
+      index += 1
+      return index
+    },
+    endof: (index) => {
+      if (index === -1) {
+        items.push({id, type: 'separator'})
+        index = items.length - 1
+      }
+
+      index += 1
+      while (index < items.length && items[index].type !== 'separator') index += 1
+      return index
+    }
+  }
+
+  // return new index if needed, or original indexOfItemById
+  return (query in queries) ? queries[query](idx) : idx
+}
+
+function insertItemByType (item, pos) {
+  const types = {
+    normal: () => this.insertItem(pos, item.commandId, item.label),
+    checkbox: () => this.insertCheckItem(pos, item.commandId, item.label),
+    separator: () => this.insertSeparator(pos),
+    submenu: () => this.insertSubMenu(pos, item.commandId, item.label, item.submenu),
+    radio: () => {
+      // Grouping radio menu items
+      item.overrideReadOnlyProperty('groupId', generateGroupId(this.items, pos))
+      if (this.groupsMap[item.groupId] == null) {
+        this.groupsMap[item.groupId] = []
+      }
+      this.groupsMap[item.groupId].push(item)
+
+      // Setting a radio menu item should flip other items in the group.
+      v8Util.setHiddenValue(item, 'checked', item.checked)
+      Object.defineProperty(item, 'checked', {
+        enumerable: true,
+        get: () => v8Util.getHiddenValue(item, 'checked'),
+        set: () => {
+          this.groupsMap[item.groupId].forEach(other => {
+            if (other !== item) v8Util.setHiddenValue(other, 'checked', false)
+          })
+          v8Util.setHiddenValue(item, 'checked', true)
+        }
+      })
+      this.insertRadioItem(pos, item.commandId, item.label, item.groupId)
+    }
+  }
+  types[item.type]()
+}
+
 module.exports = Menu
diff --git a/spec/api-menu-spec.js b/spec/api-menu-spec.js
index 4389f9d50db7..2c422b340dc3 100644
--- a/spec/api-menu-spec.js
+++ b/spec/api-menu-spec.js
@@ -7,7 +7,7 @@ const {closeWindow} = require('./window-helpers')
 describe('menu module', function () {
   describe('Menu.buildFromTemplate', function () {
     it('should be able to attach extra fields', function () {
-      var menu = Menu.buildFromTemplate([
+      const menu = Menu.buildFromTemplate([
         {
           label: 'text',
           extra: 'field'
@@ -17,7 +17,7 @@ describe('menu module', function () {
     })
 
     it('does not modify the specified template', function () {
-      var template = ipcRenderer.sendSync('eval', "var template = [{label: 'text', submenu: [{label: 'sub'}]}];\nrequire('electron').Menu.buildFromTemplate(template);\ntemplate;")
+      const template = ipcRenderer.sendSync('eval', "var template = [{label: 'text', submenu: [{label: 'sub'}]}];\nrequire('electron').Menu.buildFromTemplate(template);\ntemplate;")
       assert.deepStrictEqual(template, [
         {
           label: 'text',
@@ -47,7 +47,7 @@ describe('menu module', function () {
 
     describe('Menu.buildFromTemplate should reorder based on item position specifiers', function () {
       it('should position before existing item', function () {
-        var menu = Menu.buildFromTemplate([
+        const menu = Menu.buildFromTemplate([
           {
             label: '2',
             id: '2'
@@ -66,7 +66,7 @@ describe('menu module', function () {
       })
 
       it('should position after existing item', function () {
-        var menu = Menu.buildFromTemplate([
+        const menu = Menu.buildFromTemplate([
           {
             label: '1',
             id: '1'
@@ -85,7 +85,7 @@ describe('menu module', function () {
       })
 
       it('should position at endof existing separator groups', function () {
-        var menu = Menu.buildFromTemplate([
+        const menu = Menu.buildFromTemplate([
           {
             type: 'separator',
             id: 'numbers'
@@ -129,7 +129,7 @@ describe('menu module', function () {
       })
 
       it('should create separator group if endof does not reference existing separator group', function () {
-        var menu = Menu.buildFromTemplate([
+        const menu = Menu.buildFromTemplate([
           {
             label: 'a',
             id: 'a',
@@ -167,7 +167,7 @@ describe('menu module', function () {
       })
 
       it('should continue inserting items at next index when no specifier is present', function () {
-        var menu = Menu.buildFromTemplate([
+        const menu = Menu.buildFromTemplate([
           {
             label: '4',
             id: '4'
@@ -197,7 +197,7 @@ describe('menu module', function () {
 
   describe('Menu.getMenuItemById', function () {
     it('should return the item with the given id', function () {
-      var menu = Menu.buildFromTemplate([
+      const menu = Menu.buildFromTemplate([
         {
           label: 'View',
           submenu: [
@@ -220,7 +220,7 @@ describe('menu module', function () {
 
   describe('Menu.insert', function () {
     it('should store item in @items by its index', function () {
-      var menu = Menu.buildFromTemplate([
+      const menu = Menu.buildFromTemplate([
         {
           label: '1'
         }, {
@@ -229,9 +229,9 @@ describe('menu module', function () {
           label: '3'
         }
       ])
-      var item = new MenuItem({
-        label: 'inserted'
-      })
+
+      const item = new MenuItem({ label: 'inserted' })
+
       menu.insert(1, item)
       assert.equal(menu.items[0].label, '1')
       assert.equal(menu.items[1].label, 'inserted')
@@ -240,33 +240,71 @@ describe('menu module', function () {
     })
   })
 
+  describe('Menu.append', function () {
+    it('should add the item to the end of the menu', function () {
+      const menu = Menu.buildFromTemplate([
+        {
+          label: '1'
+        }, {
+          label: '2'
+        }, {
+          label: '3'
+        }
+      ])
+      const item = new MenuItem({ label: 'inserted' })
+
+      menu.append(item)
+      assert.equal(menu.items[0].label, '1')
+      assert.equal(menu.items[1].label, '2')
+      assert.equal(menu.items[2].label, '3')
+      assert.equal(menu.items[3].label, 'inserted')
+    })
+  })
+
   describe('Menu.popup', function () {
     let w = null
+    let menu
 
-    afterEach(function () {
+    beforeEach(() => {
+      w = new BrowserWindow({show: false, width: 200, height: 200})
+      menu = Menu.buildFromTemplate([
+        {
+          label: '1'
+        }, {
+          label: '2'
+        }, {
+          label: '3'
+        }
+      ])
+    })
+
+    afterEach(() => {
       return closeWindow(w).then(function () { w = null })
     })
 
     describe('when called with async: true', function () {
       it('returns immediately', function () {
-        w = new BrowserWindow({show: false, width: 200, height: 200})
-        const menu = Menu.buildFromTemplate([
-          {
-            label: '1'
-          }, {
-            label: '2'
-          }, {
-            label: '3'
-          }
-        ])
         menu.popup(w, {x: 100, y: 100, async: true})
         menu.closePopup(w)
       })
     })
   })
+
+  describe('Menu.setApplicationMenu', function () {
+    const menu = Menu.buildFromTemplate([
+      {
+        label: '1'
+      }, {
+        label: '2'
+      }
+    ])
+    Menu.setApplicationMenu(menu)
+    assert.notEqual(Menu.getApplicationMenu(), null)
+  })
+
   describe('MenuItem.click', function () {
     it('should be called with the item object passed', function (done) {
-      var menu = Menu.buildFromTemplate([
+      const menu = Menu.buildFromTemplate([
         {
           label: 'text',
           click: function (item) {
@@ -282,7 +320,7 @@ describe('menu module', function () {
 
   describe('MenuItem with checked property', function () {
     it('clicking an checkbox item should flip the checked property', function () {
-      var menu = Menu.buildFromTemplate([
+      const menu = Menu.buildFromTemplate([
         {
           label: 'text',
           type: 'checkbox'
@@ -294,7 +332,7 @@ describe('menu module', function () {
     })
 
     it('clicking an radio item should always make checked property true', function () {
-      var menu = Menu.buildFromTemplate([
+      const menu = Menu.buildFromTemplate([
         {
           label: 'text',
           type: 'radio'
@@ -307,99 +345,91 @@ describe('menu module', function () {
     })
 
     it('at least have one item checked in each group', function () {
-      var i, j, k, menu, template
-      template = []
-      for (i = j = 0; j <= 10; i = ++j) {
+      const template = []
+      for (let i = 0; i <= 10; i++) {
         template.push({
-          label: '' + i,
+          label: `${i}`,
           type: 'radio'
         })
       }
-      template.push({
-        type: 'separator'
-      })
-      for (i = k = 12; k <= 20; i = ++k) {
+      template.push({type: 'separator'})
+      for (let i = 12; i <= 20; i++) {
         template.push({
-          label: '' + i,
+          label: `${i}`,
           type: 'radio'
         })
       }
-      menu = Menu.buildFromTemplate(template)
+      const menu = Menu.buildFromTemplate(template)
       menu.delegate.menuWillShow()
       assert.equal(menu.items[0].checked, true)
       assert.equal(menu.items[12].checked, true)
     })
 
     it('should assign groupId automatically', function () {
-      var groupId, i, j, k, l, m, menu, template
-      template = []
-      for (i = j = 0; j <= 10; i = ++j) {
+      const template = []
+      for (let i = 0; i <= 10; i++) {
         template.push({
-          label: '' + i,
+          label: `${i}`,
           type: 'radio'
         })
       }
-      template.push({
-        type: 'separator'
-      })
-      for (i = k = 12; k <= 20; i = ++k) {
+      template.push({type: 'separator'})
+      for (let i = 12; i <= 20; i++) {
         template.push({
-          label: '' + i,
+          label: `${i}`,
           type: 'radio'
         })
       }
-      menu = Menu.buildFromTemplate(template)
-      groupId = menu.items[0].groupId
-      for (i = l = 0; l <= 10; i = ++l) {
+      const menu = Menu.buildFromTemplate(template)
+      const groupId = menu.items[0].groupId
+      for (let i = 0; i <= 10; i++) {
         assert.equal(menu.items[i].groupId, groupId)
       }
-      for (i = m = 12; m <= 20; i = ++m) {
+      for (let i = 12; i <= 20; i++) {
         assert.equal(menu.items[i].groupId, groupId + 1)
       }
     })
 
     it("setting 'checked' should flip other items' 'checked' property", function () {
-      var i, j, k, l, m, menu, n, o, p, q, template
-      template = []
-      for (i = j = 0; j <= 10; i = ++j) {
+      const template = []
+      for (let i = 0; i <= 10; i++) {
         template.push({
-          label: '' + i,
+          label: `${i}`,
           type: 'radio'
         })
       }
-      template.push({
-        type: 'separator'
-      })
-      for (i = k = 12; k <= 20; i = ++k) {
+      template.push({type: 'separator'})
+      for (let i = 12; i <= 20; i++) {
         template.push({
-          label: '' + i,
+          label: `${i}`,
           type: 'radio'
         })
       }
-      menu = Menu.buildFromTemplate(template)
-      for (i = l = 0; l <= 10; i = ++l) {
+
+      const menu = Menu.buildFromTemplate(template)
+      for (let i = 0; i <= 10; i++) {
         assert.equal(menu.items[i].checked, false)
       }
       menu.items[0].checked = true
       assert.equal(menu.items[0].checked, true)
-      for (i = m = 1; m <= 10; i = ++m) {
+      for (let i = 1; i <= 10; i++) {
         assert.equal(menu.items[i].checked, false)
       }
       menu.items[10].checked = true
       assert.equal(menu.items[10].checked, true)
-      for (i = n = 0; n <= 9; i = ++n) {
+      for (let i = 0; i <= 9; i++) {
         assert.equal(menu.items[i].checked, false)
       }
-      for (i = o = 12; o <= 20; i = ++o) {
+      for (let i = 12; i <= 20; i++) {
         assert.equal(menu.items[i].checked, false)
       }
       menu.items[12].checked = true
       assert.equal(menu.items[10].checked, true)
-      for (i = p = 0; p <= 9; i = ++p) {
+      for (let i = 0; i <= 9; i++) {
         assert.equal(menu.items[i].checked, false)
       }
       assert.equal(menu.items[12].checked, true)
-      for (i = q = 13; q <= 20; i = ++q) {
+      for (let i = 13; i <= 20; i++) {
         assert.equal(menu.items[i].checked, false)
       }
     })
@@ -407,20 +437,18 @@ describe('menu module', function () {
 
   describe('MenuItem command id', function () {
     it('cannot be overwritten', function () {
-      var item = new MenuItem({
-        label: 'item'
-      })
+      const item = new MenuItem({label: 'item'})
 
-      var commandId = item.commandId
-      assert(commandId != null)
-      item.commandId = '' + commandId + '-modified'
+      const commandId = item.commandId
+      assert(commandId)
+      item.commandId = `${commandId}-modified`
       assert.equal(item.commandId, commandId)
     })
   })
 
   describe('MenuItem with invalid type', function () {
     it('throws an exception', function () {
-      assert.throws(function () {
+      assert.throws(() => {
         Menu.buildFromTemplate([
           {
             label: 'text',
@@ -433,7 +461,7 @@ describe('menu module', function () {
 
   describe('MenuItem with submenu type and missing submenu', function () {
     it('throws an exception', function () {
-      assert.throws(function () {
+      assert.throws(() => {
         Menu.buildFromTemplate([
           {
             label: 'text',
@@ -446,7 +474,7 @@ describe('menu module', function () {
 
   describe('MenuItem role', function () {
     it('includes a default label and accelerator', function () {
-      var item = new MenuItem({role: 'close'})
+      let item = new MenuItem({role: 'close'})
       assert.equal(item.label, process.platform === 'darwin' ? 'Close Window' : 'Close')
       assert.equal(item.accelerator, undefined)
       assert.equal(item.getDefaultRoleAccelerator(), 'CommandOrControl+W')
@@ -480,7 +508,7 @@ describe('menu module', function () {
 
   describe('MenuItem editMenu', function () {
     it('includes a default submenu layout when submenu is empty', function () {
-      var item = new MenuItem({role: 'editMenu'})
+      const item = new MenuItem({role: 'editMenu'})
       assert.equal(item.label, 'Edit')
       assert.equal(item.submenu.items[0].role, 'undo')
       assert.equal(item.submenu.items[1].role, 'redo')
@@ -503,7 +531,7 @@ describe('menu module', function () {
     })
 
     it('overrides default layout when submenu is specified', function () {
-      var item = new MenuItem({role: 'editMenu', submenu: [{role: 'close'}]})
+      const item = new MenuItem({role: 'editMenu', submenu: [{role: 'close'}]})
       assert.equal(item.label, 'Edit')
       assert.equal(item.submenu.items[0].role, 'close')
     })
@@ -511,7 +539,7 @@ describe('menu module', function () {
 
   describe('MenuItem windowMenu', function () {
     it('includes a default submenu layout when submenu is empty', function () {
-      var item = new MenuItem({role: 'windowMenu'})
+      const item = new MenuItem({role: 'windowMenu'})
       assert.equal(item.label, 'Window')
       assert.equal(item.submenu.items[0].role, 'minimize')
       assert.equal(item.submenu.items[1].role, 'close')
@@ -523,7 +551,7 @@ describe('menu module', function () {
     })
 
     it('overrides default layout when submenu is specified', function () {
-      var item = new MenuItem({role: 'windowMenu', submenu: [{role: 'copy'}]})
+      const item = new MenuItem({role: 'windowMenu', submenu: [{role: 'copy'}]})
       assert.equal(item.label, 'Window')
       assert.equal(item.submenu.items[0].role, 'copy')
     })
@@ -531,13 +559,13 @@ describe('menu module', function () {
 
   describe('MenuItem with custom properties in constructor', function () {
     it('preserves the custom properties', function () {
-      var template = [{
+      const template = [{
         label: 'menu 1',
         customProp: 'foo',
         submenu: []
       }]
 
-      var menu = Menu.buildFromTemplate(template)
+      const menu = Menu.buildFromTemplate(template)
       menu.items[0].submenu.append(new MenuItem({
         label: 'item 1',
         customProp: 'bar',