module ActiveRecord module Associations class HasOneAssociation < BelongsToAssociation #:nodoc: def initialize(owner, association_name, association_class_name, association_class_primary_key_name, options) super construct_sql end def replace(obj, dont_save = false) load_target unless @target.nil? @target[@association_class_primary_key_name] = nil @target.save unless @owner.new_record? end if obj.nil? @target = nil else raise_on_type_mismatch(obj) obj[@association_class_primary_key_name] = @owner.id unless @owner.new_record? @target = obj end @loaded = true unless @owner.new_record? or obj.nil? or dont_save return (obj.save ? self : false) else return (obj.nil? ? nil : self) end end private def find_target @association_class.find_first(@finder_sql, @options[:order]) end def target_obsolete? false end def construct_sql @finder_sql = "#{@association_class_primary_key_name} = #{@owner.quoted_id}#{@options[:conditions] ? " AND " + @options[:conditions] : ""}" end end end end