【发布时间】：2012-01-13 23:00:57
【问题描述】：
剧透：这是 rspec-rails gem 的过时版本！
在将我的 sqlite3 gem 移动到开发块中然后运行“rake db:migrate”以确保一切仍然正常之后，我在 rails 项目目录发出的任何 rake 命令都遇到了这个错误。 Rake 在我系统的其他地方工作正常。但是我在该目录中运行的任何 rake 任务都会给我以下输出和跟踪：
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rspec-rails-2.0.0.beta.18/lib/rspec/rails/tasks/rspec.rake:3:in `<top (required)>'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rspec-rails-2.0.0.beta.18/lib/rspec-rails.rb:8:in `load'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rspec-rails-2.0.0.beta.18/lib/rspec-rails.rb:8:in `block in <class:Railtie>'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/railtie.rb:183:in `call'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/railtie.rb:183:in `block in load_tasks'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/railtie.rb:183:in `each'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/railtie.rb:183:in `load_tasks'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/engine.rb:396:in `block in load_tasks'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/application/railties.rb:8:in `each'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/application/railties.rb:8:in `all'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/engine.rb:396:in `load_tasks'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/application.rb:103:in `load_tasks'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.1.3/lib/rails/railtie/configurable.rb:30:in `method_missing'
/Users/ianyoung/rails/third_app/Rakefile:7:in `<top (required)>'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/rake_module.rb:25:in `load'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/rake_module.rb:25:in `load_rakefile'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:501:in `raw_load_rakefile'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:82:in `block in load_rakefile'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:81:in `load_rakefile'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:65:in `block in run'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2.2/bin/rake:33:in `<top (required)>'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/bin/rake:19:in `load'
/Users/ianyoung/.rvm/gems/ruby-1.9.2-p290/bin/rake:19:in `<main>'
我得到的第一个错误是问题标题： 耙中止！ nil:NilClass 的未定义方法“先决条件”
我也遇到过这个问题，但它并没有给我带来问题。也许它是相关的？：
弃用警告：Rails::Railtie 中的 config.generators 已弃用。请改用 config.app_generators。 （从 /Users/ianyoung/rails/third_app/config/application.rb:13 调用） 弃用警告：Rails::Railtie 中的 config.generators 已弃用。请改用 config.app_generators。 （从 /Users/ianyoung/rails/third_app/config/application.rb:13 调用）
【问题讨论】：
-
你为什么要使用这么旧版本的 rspec-rails？
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这是一个非常旧的 rspec-rails 版本，很可能被更新版本的 rake 破解。我会先尝试更新 rspec-rails
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我正在使用该版本的 rspec-rails，因为我正在关注 Hartl 的 ROR 教程。我使用的另一个版本是 has_selector 方法给我的错误。我将尝试该 gem 的不同版本。
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新版本的 rspec-rails 做到了。谢谢你。张先生，您能允许我给您做绿检吗？
标签： ruby-on-rails ruby rake