尝试使用 rails 3.2 进行新项目时遇到此错误。哈姆问题?
rails generate rspec:install
/home/me/.rvm/gems/ruby-1.9.2-p290/gems/haml-3.1.3/lib/haml/template/patch.rb:16:
in `alias_method': undefined method `delegate_template_exists?'
for class `ActionView::Base' (NameError)