title: How can I configure Rails to raise an error when it hits a deprecation warning?
body: <p>I'm upgrading a rather large app from Rails 3.0 to 3.2, and trying to get rid of all the deprecation warnings. My question isn't what to change to resolve particular warnings, but how to get Rails to treat them like exceptions so it will dump a stack trace in dev mode, so I'll have the full stack trace to see where the offending code is coming from. That way I can just use my test suite to find them all, and verify that they're all cleaned up. If there's a way to get rspec to fail a test if it logs a deprecation warning, that would work as well. </p>
  
  <p>(In case anyone wonders, the reason I'm not upgrading all the way to rails 4.0 is that the app depends on some gems that AFAIK aren't fully ready for rails 4 yet, especially activerecord-oracle_enhanced-adapter.)</p>