RSpec instead of Test::Unit for new Rails projects

gistfile1.sh

# at command line:
rails new MYAPP -T # The -T option tells rails not to include Test::Unit

# in Gemfile:
gem 'rspec-rails'

# in config/initializers/generator.rb
Rails.application.config.generators do |g|
  g.test_framework = :rspec
end

# at command line:
bundle install
rails g rspec:install