我有一个Rails应用程序，我正在升级到Rails 4.1.4。我还有一个RSpec测试套件，我想用更新的Rails版本对应用程序运行。应用程序不使用数据库，只是与服务进行通信。但是，当我尝试运行测试时，我收到此错误：
Failure/Error: Unable to find matching line from backtrace
ActiveRecord::ConnectionNotEstablished:
ActiveRecord::ConnectionNotEstablished
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-4.1.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:541:in `retrieve_connection'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-4.1.4/lib/active_record/connection_handling.rb:113:in `retrieve_connection'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-4.1.4/lib/active_record/connection_handling.rb:87:in `connection'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-4.1.4/lib/active_record/fixtures.rb:499:in `create_fixtures'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-4.1.4/lib/active_record/fixtures.rb:984:in `load_fixtures'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-4.1.4/lib/active_record/fixtures.rb:957:in `setup_fixtures'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/activerecord-4.1.4/lib/active_record/fixtures.rb:806:in `before_setup'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-rails-2.99.0/lib/rspec/rails/adapters.rb:68:in `block (2 levels) in <module:MinitestLifecycleAdapter>'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/extensions/instance_eval_with_args.rb:16:in `instance_exec'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/extensions/instance_eval_with_args.rb:16:in `instance_eval_with_args'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/example.rb:241:in `instance_eval_with_args'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/hooks.rb:106:in `block (2 levels) in run'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/hooks.rb:104:in `call'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/hooks.rb:104:in `run'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/hooks.rb:446:in `run_hook'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/example_group.rb:462:in `run_around_each_hooks'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/example.rb:250:in `with_around_each_hooks'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/example.rb:113:in `run'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/example_group.rb:514:in `block in run_examples'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/example_group.rb:510:in `map'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/example_group.rb:510:in `run_examples'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/example_group.rb:495:in `run'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/command_line.rb:24:in `block (2 levels) in run'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/command_line.rb:24:in `map'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/command_line.rb:24:in `block in run'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/reporter.rb:58:in `report'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/command_line.rb:21:in `run'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/runner.rb:103:in `run'
# /Users/karianneberg/.rvm/gems/ruby-1.9.3-p484/gems/rspec-core-2.99.1/lib/rspec/core/runner.rb:17:in `block in autorun'
我不明白为什么它会尝试启动活动记录
当我不通过测试运行它时，应用程序运行正常，并且测试在Rails 4.0上运行得很好。我还在使用RSpec-rails 2.99。有谁知道问题可能是什么？