耙子流产了!不能加载这样的文件 - 码

我一直试图从源代码添加一个vagrant插件(https://github.com/schisamo/vagrant-omnibus).我下载了它,做了"捆绑安装",顺利进行.但当我做"rake install"时,它向我显示以下错误:

rake aborted!
cannot load such file -- yard

这是带跟踪的完整错误日志:

rake aborted!
cannot load such file -- yard
/root/chef-solo-example/vagrant-omnibus-master/Rakefile:5:in `require'
/root/chef-solo-example/vagrant-omnibus-master/Rakefile:5:in `'
/usr/share/gems/gems/rake-10.0.4/lib/rake/rake_module.rb:25:in `load'
/usr/share/gems/gems/rake-10.0.4/lib/rake/rake_module.rb:25:in `load_rakefile'
/usr/share/gems/gems/rake-10.0.4/lib/rake/application.rb:589:in `raw_load_rakefile'
/usr/share/gems/gems/rake-10.0.4/lib/rake/application.rb:89:in `block in load_rakefile'
/usr/share/gems/gems/rake-10.0.4/lib/rake/application.rb:160:in `standard_exception_handling'
/usr/share/gems/gems/rake-10.0.4/lib/rake/application.rb:88:in `load_rakefile'
/usr/share/gems/gems/rake-10.0.4/lib/rake/application.rb:72:in `block in run'
/usr/share/gems/gems/rake-10.0.4/lib/rake/application.rb:160:in `standard_exception_handling'
/usr/share/gems/gems/rake-10.0.4/lib/rake/application.rb:70:in `run'
/usr/share/gems/gems/rake-10.0.4/bin/rake:33:in `'
/bin/rake:23:in `load'
/bin/rake:23:in `
'

这是宝石列表:

*** LOCAL GEMS ***

archive-tar-minitar (0.5.2)
ast (1.1.0)
bigdecimal (1.2.0)
bundler (1.3.1)
chef (11.8.2)
chef-zero (1.7.2)
coderay (1.1.0)
diff-lcs (1.2.5)
erubis (2.7.0)
hashie (2.0.5)
highline (1.6.20)
io-console (0.4.2)
ipaddress (0.8.0)
json (1.7.7)
knife-solo (0.4.1)
librarian (0.1.0)
librarian-chef (0.0.2)
method_source (0.8.2)
mime-types (1.16)
mixlib-authentication (1.3.0)
mixlib-cli (1.4.0)
mixlib-config (2.1.0)
mixlib-log (1.6.0)
mixlib-shellout (1.3.0)
moneta (0.7.20, 0.7.0, 0.6.0)
net-http-persistent (2.8)
net-ssh (2.7.0)
net-ssh-gateway (1.2.0)
net-ssh-multi (1.2.0, 1.1)
ohai (6.20.0)
parser (2.0.0)
powerpack (0.0.9, 0.0.6)
pry (0.9.12.4)
psych (2.0.0)
puma (1.6.0)
rack (1.5.2)
rainbow (1.1.4)
rake (10.0.4)
rake-compiler (0.8.3)
rdoc (4.0.1)
rest-client (1.6.7)
rspec (2.14.1)
rspec-core (2.14.0)
rspec-expectations (2.14.0)
rspec-mocks (2.14.0)
rubocop (0.15.0)
slop (3.4.7)
systemu (2.6.0, 2.5.2)
thor (0.17.0)
yajl-ruby (1.1.0)
yard (0.8.7.3)

知道什么可能导致这个错误？