preserve custom properties passed to MenuItem constructor

lib/browser/api/menu-item.js

@@ -7,18 +7,8 @@ let nextCommandId = 0
 const MenuItem = function (options) {
   const {Menu} = require('electron')
 
-  this.selector = options.selector
-  this.type = options.type
-  this.role = options.role
-  this.label = options.label
-  this.sublabel = options.sublabel
-  this.accelerator = options.accelerator
-  this.icon = options.icon
-  this.enabled = options.enabled
-  this.visible = options.visible
-  this.checked = options.checked
+  Object.assign(this, options)
 
-  this.submenu = options.submenu
   if (this.submenu != null && this.submenu.constructor !== Menu) {
     this.submenu = Menu.buildFromTemplate(this.submenu)
   }
@@ -70,10 +60,7 @@ MenuItem.prototype.getDefaultRoleAccelerator = function () {
   return roles.getDefaultAccelerator(this.role)
 }
 
-MenuItem.prototype.overrideProperty = function (name, defaultValue) {
-  if (defaultValue == null) {
-    defaultValue = null
-  }
+MenuItem.prototype.overrideProperty = function (name, defaultValue = null) {
   if (this[name] == null) {
     this[name] = defaultValue
   }

spec/api-menu-spec.js

@@ -430,3 +430,23 @@ describe('menu module', function () {
     })
   })
 })
+
+describe('MenuItem with custom properties in constructor', function () {
+  it('preserves the custom properties', function () {
+    var template = [{
+      label: 'menu 1',
+      customProp: 'foo',
+      submenu: []
+    }]
+
+    var menu = new Menu.buildFromTemplate(template)
+    menu.items[0].submenu.append(new MenuItem({
+      label: 'item 1',
+      customProp: 'bar'
+    }))
+
+    assert.equal(menu.items[0].customProp, 'foo')
+    assert.equal(menu.items[0].submenu.items[0].label, 'item 1')
+    assert.equal(menu.items[0].submenu.items[0].customProp, 'bar')
+  })
+})