module ActiveRecord::AttributeMethods::Query  
        Active Record Attribute Methods Query
Public instance methods
              Also aliased as:
              
              attribute?.
            
Source code GitHub
# File activerecord/lib/active_record/attribute_methods/query.rb, line 13
def query_attribute(attr_name)
  value = self.public_send(attr_name)
  query_cast_attribute(attr_name, value)
end