title: Rails 3.0.7 rake functional test gave strange error in "file_utils.rb:53:in `block in create_shell_runner'"
body: <p>The strange part is that, the previous run worked fine and listed 20+ failure/errors. I fixed each individual functional test one by one. Then I ran the full functional test and got below error without telling me which specific functional test failed. </p>
  
  <p>Can any Rails Guru shed some light on this issue?  Thanks in advance. </p>
  
  <pre>
  /demoslm$ rake test:functionals --trace  > test_2.txt
  WARNING: 'require 'rake/rdoctask'' is deprecated.  Please use 'require 'rdoc/task' (in RDoc 2.4.2+)' instead.
      at /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/rdoctask.rb
  ** Invoke test:functionals (first_time)
  ** Invoke test:prepare (first_time)
  ** Invoke db:test:prepare (first_time)
  ** Invoke db:abort_if_pending_migrations (first_time)
  ** Invoke environment (first_time)
  ** Execute environment
  ** Execute db:abort_if_pending_migrations
  ** Execute db:test:prepare
  ** Invoke db:test:clone_structure (first_time)
  ** Invoke db:structure:dump (first_time)
  ** Invoke environment 
  ** Execute db:structure:dump
  ** Invoke db:test:purge (first_time)
  ** Invoke environment 
  ** Execute db:test:purge
  ** Execute db:test:clone_structure
  ** Execute test:prepare
  ** Execute test:functionals
  rake aborted!
  Command failed with status (1): [/home/ubuntu/.rvm/rubies/ruby-1.9.2-p180/b...]
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/file_utils.rb:53:in `block in create_shell_runner'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/file_utils.rb:45:in `call'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/file_utils.rb:45:in `sh'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/file_utils_ext.rb:39:in `sh'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/file_utils.rb:82:in `ruby'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/file_utils_ext.rb:39:in `ruby'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.7/lib/rails/test_unit/testing.rake:26:in `block (2 levels) in define'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/file_utils_ext.rb:60:in `verbose'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.7/lib/rails/test_unit/testing.rake:11:in `block in define'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `call'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `block in execute'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `each'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `execute'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/task.rb:158:in `block in invoke_with_call_chain'
  /home/ubuntu/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/task.rb:144:in `invoke'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:116:in `invoke_task'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block (2 levels) in top_level'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `each'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `block in top_level'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:88:in `top_level'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:66:in `block in run'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/gems/rake-0.9.2.2/bin/rake:33:in `'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/bin/rake:19:in `load'
  /home/ubuntu/.rvm/gems/ruby-1.9.2-p180/bin/rake:19:in `'
  Tasks: TOP => test:functionals
  </pre>