title: How do I get a full stack trace instead of "Unexpected error while processing request" in Rails test environment?
body: <p>When starting my rails server in test environment (<code>rails s -e test</code>), something is rescuing exceptions and outputs instead "Unexpected error while processing request: ...error here...". I get the backtrace in development mode.</p>
  
  <p>Who is it, and how can I disable that? I need the full backtrace, not just the error that was raised!</p>
  
  <p>I'm using Rails 3.2.3, Ruby 1.9.3, rspec, capybara, capybara-webkit</p>