在执行命令以测试我的整个应用程序时，我收到以下错误：
rspec spec/
/Users/ivankutsarov/railstwitter/twitter/spec/requests/static_pages_spec.rb:5:in `<top (required)>': undefined method `subject' for main:Object (NoMethodError)
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.2.8/lib/active_support/dependencies.rb:245:in `load'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.2.8/lib/active_support/dependencies.rb:245:in `block in load'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.2.8/lib/active_support/dependencies.rb:236:in `load_dependency'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/activesupport-3.2.8/lib/active_support/dependencies.rb:245:in `load'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/rspec-core-2.11.1/lib/rspec/core/configuration.rb:780:in `block in load_spec_files'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/rspec-core-2.11.1/lib/rspec/core/configuration.rb:780:in `map'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/rspec-core-2.11.1/lib/rspec/core/configuration.rb:780:in `load_spec_files'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/rspec-core-2.11.1/lib/rspec/core/command_line.rb:22:in `run'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/rspec-core-2.11.1/lib/rspec/core/runner.rb:69:in `run'
from /Users/ivankutsarov/.rvm/gems/ruby-1.9.3-p194/gems/rspec-core-2.11.1/lib/rspec/core/runner.rb:8:in `block in autorun'