Question

I am running Rails 3.1.1 and getting this error when running this command. Obviously new to Rails, any help appreciated:

rake aborted!
undefined method `prerequisites’ for nil:NilClass

/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rspec-rails-2.6.0/lib/rspec/rails/tasks/rspec.rake:3:in `<top (required)>'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rspec-rails-2.6.0/lib/rspec-rails.rb:10:in `load'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rspec-rails-2.6.0/lib/rspec-rails.rb:10:in `block in <class:Railtie>'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/railtie.rb:183:in `call'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/railtie.rb:183:in `block in load_tasks'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/railtie.rb:183:in `each'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/railtie.rb:183:in `load_tasks'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/engine.rb:396:in `block in load_tasks'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/application/railties.rb:8:in `each'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/application/railties.rb:8:in `all'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/engine.rb:396:in `load_tasks'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/application.rb:103:in `load_tasks'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/railties-3.1.1/lib/rails/railtie/configurable.rb:30:in `method_missing'
/Users/220040168/rails_projects/sample_app/Rakefile:7:in `<top (required)>'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/rake_module.rb:25:in `load'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/rake_module.rb:25:in `load_rakefile'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/application.rb:501:in `raw_load_rakefile'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/application.rb:82:in `block in load_rakefile'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/application.rb:81:in `load_rakefile'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/application.rb:65:in `block in run'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/gems/rake-0.9.2.2/bin/rake:33:in `<top (required)>'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/bin/rake:19:in `load'
/Users/220040168/.rvm/gems/ruby-1.9.2-p290@rails3tutorial/bin/rake:19:in `<main>'

Not the first time I have run this command, but first time I am getting this error.

GEMFILE

source 'http://rubygems.org'

gem 'rails', '3.1.1'

# Bundle edge Rails instead:
# gem 'rails',     :git => 'git://github.com/rails/rails.git'

gem 'sqlite3'

group :development do
    gem 'rspec-rails', '2.6.0'
end

group :test do
    gem 'rspec', '2.6.0'
    gem 'webrat', '0.7.1'
    gem 'autotest', '4.3.2'
    gem 'autotest-rails-pure', '4.1.0'
    gem 'autotest-fsevent', '0.2.2'
    gem 'autotest-growl', '0.2.4'
end


# Gems used only for assets and not required
# in production environments by default.
group :assets do
  gem 'sass-rails',   '~> 3.1.4'
  gem 'coffee-rails', '~> 3.1.1'
  gem 'uglifier', '>= 1.0.3'
end

gem 'jquery-rails'

# To use ActiveModel has_secure_password
# gem 'bcrypt-ruby', '~> 3.0.0'

# Use unicorn as the web server
# gem 'unicorn'

# Deploy with Capistrano
# gem 'capistrano'

# To use debugger
# gem 'ruby-debug19', :require => 'ruby-debug'

Answer 1

Looks related to this issue https://github.com/rails/rails/issues/1197
Try to upgrade to a newer rspec-rails version than 2.6.0