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 create(attributes = {}, replace_existing = true) record = build(attributes, replace_existing) record.save record end def build(attributes = {}, replace_existing = true) record = @association_class.new(attributes) if replace_existing replace(record, true) else record[@association_class_primary_key_name] = @owner.id unless @owner.new_record? self.target = record end record end def replace(obj, dont_save = false) load_target unless @target.nil? if dependent? && !dont_save && @target != obj @target.destroy unless @target.new_record? @owner.clear_association_cache else @target[@association_class_primary_key_name] = nil @target.save unless @owner.new_record? end 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 = (AssociationProxy === obj ? obj.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, :conditions => @finder_sql, :order => @options[:order]) end def target_obsolete? false end def construct_sql @finder_sql = "#{@association_class.table_name}.#{@association_class_primary_key_name} = #{@owner.quoted_id}#{@options[:conditions] ? " AND " + @options[:conditions] : ""}" @finder_sql << " AND (#{sanitize_sql(@options[:conditions])})" if @options[:conditions] @finder_sql end end end end