Ruby on rails Rails测试失败

每当我运行下面的代码时，终端上总是会出现这些错误

rake test  or bundle exec rake test

/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `require': cannot load such file -- guard (LoadError)
from /usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `block in require'
from /usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:240:in `load_dependency'
from /usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `require'
from /usr/local/lib/ruby/gems/2.2.0/gems/guard-minitest-2.4.4/lib/minitest/guard_minitest_plugin.rb:4:in `<top (required)>'
from /usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `require'
from /usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `block in require'
from /usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:240:in `load_dependency'
from /usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:274:in `require'
from /usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:91:in `block in load_plugins'
from /usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:85:in `each'
from /usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:85:in `load_plugins'
from /usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:114:in `run'
from /usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:56:in `block in autorun'

rake测试或bundle exec rake测试
/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active\u support/dependencies.rb:274:在'require'中：无法加载这样的文件--guard（LoadError）
来自/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active\u support/dependencies.rb:274:in'block in require'
from/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active\u support/dependencies.rb:240:in'load\u dependency'
来自/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active\u support/dependencies.rb:274:in'require'
来自/usr/local/lib/ruby/gems/2.2.0/gems/guard-minitest-2.4.4/lib/minitest/guard\u minitest\u plugin.rb:4:in`'
来自/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active\u support/dependencies.rb:274:in'require'
来自/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active\u support/dependencies.rb:274:in'block in require'
from/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active\u support/dependencies.rb:240:in'load\u dependency'
来自/usr/local/lib/ruby/gems/2.2.0/gems/activesupport-4.2.0/lib/active\u support/dependencies.rb:274:in'require'
from/usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:91:in'block in load_plugins'
from/usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:85:in'each'
from/usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:85:in'load_plugins'
from/usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:114:in'run'
from/usr/local/lib/ruby/gems/2.2.0/gems/minitest-5.5.1/lib/minitest.rb:56:in'block in autorun'

看起来文件中未安装/包含

防护装置。如果还没有，请将其包含在Gemfile中。然后运行
捆绑安装

有关如何使用防护罩的信息，请参阅。也是一个很好的资源。
显示导致此问题的测试代码。看起来没有安装
guard
gem；尝试运行
bundle安装
。我已经运行了，但仍然再次尝试。仍然得到相同的错误。如何安装guard gem我是否只需将gem“guard”添加到我的gemfile..@RailsOuter这里是代码他们仍然是默认的没有添加任何内容需要“test\u helper”类StaticPagesControllerTest