私は Rails と Guard を初めて使用し、エラーの数や例などを出力しているように見えるスクリーンキャストを見ています。ただし、実行すると、次の出力が表示されます。
18:31:11 - INFO - Running: spec/controllers/tasks_controller_spec.rb
/Users/Phil/.rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/test/unit/testcase.rb:9:in `<class:TestCase>': uninitialized constant Test::Unit::TestCase::Assertions (NameError)
from /Users/Phil/.rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/test/unit/testcase.rb:8:in `<module:Unit>'
from /Users/Phil/.rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/test/unit/testcase.rb:4:in `<module:Test>'
from /Users/Phil/.rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/test/unit/testcase.rb:3:in `<top (required)>'
from /Users/Phil/.rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/test/unit.rb:5:in `<top (required)>'
from /Users/Phil/.rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/test/unit/assertions.rb:4:in `<top (required)>'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-rails-2.14.0/lib/rspec/rails/adapters.rb:3:in `<top (required)>'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-rails-2.14.0/lib/rspec/rails.rb:11:in `<top (required)>'
from /Users/Phil/rails/tasks/spec/spec_helper.rb:4:in `<top (required)>'
from /Users/Phil/rails/tasks/spec/controllers/tasks_controller_spec.rb:1:in `require'
from /Users/Phil/rails/tasks/spec/controllers/tasks_controller_spec.rb:1:in `<top (required)>'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-core-2.14.3/lib/rspec/core/configuration.rb:896:in `load'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-core-2.14.3/lib/rspec/core/configuration.rb:896:in `block in load_spec_files'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-core-2.14.3/lib/rspec/core/configuration.rb:896:in `each'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-core-2.14.3/lib/rspec/core/configuration.rb:896:in `load_spec_files'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-core-2.14.3/lib/rspec/core/command_line.rb:22:in `run'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-core-2.14.3/lib/rspec/core/runner.rb:80:in `run'
from /Users/Phil/.rvm/gems/ruby-1.9.3-p448/gems/rspec-core-2.14.3/lib/rspec/core/runner.rb:17:in `block in autorun'
私は何か間違ったことをしていますか?