NamedScope#size doesn't respect limit options, if the collection isn't loaded

Given a named scope with a limit option

named_scope :limited_to_2, lambda { {:limit => 2} }

calling #size when the collection isn't loaded yet

Model.limited_to_2.size

will ignore the limit option and return the complete count of all stored Model instances.

See http://gist.github.com/118690 for a ready-to-run test case.

The fix would be:

class ActiveRecord::NamedScope::Scope
  def size
    return @found.length if @found
    
    @proxy_options[:limit] ? [@proxy_options[:limit],count].min : count
  end
end