build_conditions

# File activerecord/lib/active_record/associations/has_many_through_association.rb, line 215
        def build_conditions
          association_conditions = @reflection.options[:conditions]
          through_conditions = build_through_conditions
          source_conditions = @reflection.source_reflection.options[:conditions]
          uses_sti = [email protected]_reflection.klass.descends_from_active_record?

          if association_conditions || through_conditions || source_conditions || uses_sti
            all = []

            [association_conditions, source_conditions].each do |conditions|
              all << interpolate_sql(sanitize_sql(conditions)) if conditions
            end

            all << through_conditions  if through_conditions
            all << build_sti_condition if uses_sti

            all.map { |sql| "(#{sql})" } * ' AND '
          end
        end