Historically, we've had some issues with having the wrong call site printed in the deprecation warning.  After having a bunch of those (even AFTER adding logic to look for a non-RSpec line in the backtrace), we've started trying to always spec that since it's easy to get wrong and not simple to check manually.  We have a helper method in spec_helper.rb for it.  Use it like so:

``` ruby
obj = Object.new
expect_deprecation_with_call_site(__FILE__, __LINE__ + 1)
obj.stub(:foo).with { |x| }
```