我正在尝试使用提供的安装指南设置测量员 gem。我正在使用此处提供的surveyor-example进行工作，因此我假设我将使用旧代码进行工作。但是，当我跑步时
bundle exec rake surveyor FILE=surveys/kitchen_sink_survey.rb
它出现错误“未初始化的常量 RAILS_ROOT”。我在这里读到，解决方案是尝试使用Rails.root，但我不确定在哪里更改此设置。这是我在 environment.rb 中设置的还是在调查代码本身中设置的？
如果它提供任何进一步的帮助，以下是跟踪的结果：
/home/nitrous/surveyor_example/.bundle/bundler/gems/surveyor-a95169e36afc/lib/tasks/surveyor_tasks.rake:7:in `block (2 levels) in <top (required)>'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:205:in `call'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:205:in `block in execute'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:200:in `each'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:200:in `execute'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:158:in `block in invoke_with_call_chain'
/usr/local/opt/rbenv/versions/2.1.5/lib/ruby/2.1.0/monitor.rb:211:in `mon_synchronize'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:176:in `block in invoke_prerequisites'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:174:in `each'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:174:in `invoke_prerequisites'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:157:in `block in invoke_with_call_chain'
/usr/local/opt/rbenv/versions/2.1.5/lib/ruby/2.1.0/monitor.rb:211:in `mon_synchronize'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/task.rb:144:in `invoke'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:112:in `invoke_task'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:90:in `block (2 levels) in top_level'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:90:in `each'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:90:in `block in top_level'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:129:in `standard_exception_handling'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:84:in `top_level'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:62:in `block in run'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:129:in `standard_exception_handling'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/lib/rake/application.rb:59:in `run'
/home/nitrous/surveyor_example/.bundle/gems/rake-0.9.2/bin/rake:32:in `<top (required)>'
/home/nitrous/surveyor_example/.bundle/bin/rake:23:in `load'
/home/nitrous/surveyor_example/.bundle/bin/rake:23:in `<main>'