Update lib/mongoid_search/util.rb
Update lib/mongoid_search/util.rb

If one of the fields in "search_in" is a method, then the old-vay "klass[field]" returns nil.
With this fix it executes the method and uses its result. Also, for regular fields it also works fine.
mongoid/mongoid_search,smashwilson/mongoid_search,mauriciozaffari/mongoid_search,wizardone/mongoid_search,vanboom/mongoid_search