rake db：test：load，undefined方法`’为nil：NilClass
我想创建测试数据库。 开发数据库有以下设置：
development: adapter: mysql2 encoding: utf8 database: c9 username: host: 当我运行命令时： rake db：test：load –trace ，显示错误：
rake aborted! NoMethodError: undefined method `[]' for nil:NilClass /usr/local/rvm/gems/ruby-2.0.0-p247/gems/activerecord-3.2.22/lib/active_record/railties/databases.rake:526:in `block (3 levels) in ' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:240:in `call' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:240:in `block in execute' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:235:in `each' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:235:in `execute' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:179:in `block in invoke_with_call_chain' /usr/local/rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/monitor.rb:211:in `mon_synchronize' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:172:in `invoke_with_call_chain' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:201:in `block in invoke_prerequisites' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:199:in `each' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:199:in `invoke_prerequisites' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:178:in `block in invoke_with_call_chain' /usr/local/rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/monitor.rb:211:in `mon_synchronize' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:172:in `invoke_with_call_chain' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/task.rb:165:in `invoke' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:150:in `invoke_task' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:106:in `block (2 levels) in top_level' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:106:in `each' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:106:in `block in top_level' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:115:in `run_with_threads' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:100:in `top_level' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:78:in `block in run' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:176:in `standard_exception_handling' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/lib/rake/application.rb:75:in `run' /usr/local/rvm/gems/ruby-2.0.0-p247/gems/rake-10.4.2/bin/rake:33:in `' /usr/local/rvm/gems/ruby-2.0.0-p247/bin/rake:23:in `load' /usr/local/rvm/gems/ruby-2.0.0-p247/bin/rake:23:in `' /usr/local/rvm/gems/ruby-2.0.0-p247/bin/ruby_executable_hooks:15:in `eval' /usr/local/rvm/gems/ruby-2.0.0-p247/bin/ruby_executable_hooks:15:in `' Tasks: TOP => db:test:load => db:test:purge
怎么解决这个问题？
在database.yml中添加测试env的配置。
还要记住为测试数据库使用不同的database_name。
test: adapter: mysql2 encoding: utf8 database: c9_test username: <%=ENV['C9_USER']%> host: <%=ENV['IP']%>
然后点击此命令
RAILS_ENV=test rake db:setup
您可能希望在传递给它的特定环境下运行该命令。 可以这么说：
bundle exec rake db:test:load RAILS_ENV="development"