用于Safari的Watir-webdriver无法右键单击或双击

在Mac 10.9上，我的watir-webdriver脚本可以与Chrome和Firefox一起使用，但是使用Safari我无法右键单击或双击 . 尝试双击或右键单击给出了这个错误：

按钮可用？ true /Users/engineering/.rvm/gems/ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/webdriver/safari/bridge.rb:73:in raw_execute'：未知命令：来自/Users/engineering/.rvm/gems/ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/webdriver/remote/的mouseMoveTo（Selenium :: WebDriver :: Error :: UnknownError） bridge.rb：612：不执行'来自/Users/engineering/.rvm/gems/ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/webdriver/remote/bridge.rb:399 ：in mouseMoveTo'from /Users/engineering/.rvm/gems/ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/webdriver/common/mouse.rb:52:inmove_to'from /Users/engineering/.rvm/gems/ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/webdriver/common/mouse.rb:62:in move_if_needed'来自/ Users / engineering /.rvm/gems/ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/webdriver/common/mouse.rb:26:incontext_click'from /Users/engineering/.rvm/gems /ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/ webdriver / common / action_builder.rb：344：in block in perform'from /Users/engineering/.rvm/gems/ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/webdriver/ common / action_builder.rb：343：ineach'来自/Users/engineering/.rvm/gems/ruby-1.9.3-p484/gems/selenium-webdriver-2.40.0/lib/selenium/webdriver/common/action_builder.rb ：343：正在执行'来自/Users/engineering/.rvm/gems/ruby-1.9.3-p484/gems/watir-webdriver-0.6.8/lib/watir-webdriver/elements/element.rb:165:inright_click '来自tester.rb：10：in''

这是我的代码 . 在最后一行，如果我将右键单击方法改为左键单击，它将点击“我感觉很幸运”按钮 . 有谁知道这个错误发生的原因是什么？我刚刚开始使用Watir . 我按照以下步骤从这里获得了使用Safari的watir-webdriver：www.watirwebdriver.com/safari/

require 'watir-webdriver'
b = Watir::Browser.new :safari
b.goto "http://google.ca"

puts "button available? #{b.button(:id => 'gbqfba').exists?}"
b.button(id:'gbqfbb').span(text:"I'm Feeling Lucky").wait_until_present
b.button(id:'gbqfbb').span(text:"I'm Feeling Lucky").right_click