require 'set' module ActiveRecord module Associations class AssociationCollection < AssociationProxy #:nodoc: def to_ary load_target @target.to_ary end def reset reset_target! @loaded = false end # Add +records+ to this association. Returns +self+ so method calls may be chained. # Since << flattens its argument list and inserts each record, +push+ and +concat+ behave identically. def <<(*records) result = true load_target @owner.transaction do flatten_deeper(records).each do |record| raise_on_type_mismatch(record) callback(:before_add, record) result &&= insert_record(record) unless @owner.new_record? @target << record callback(:after_add, record) end end result && self end alias_method :push, :<< alias_method :concat, :<< # Remove all records from this association def delete_all load_target delete(@target) reset_target! end # Calculate sum using SQL, not Enumerable def sum(*args, &block) calculate(:sum, *args, &block) end # Remove +records+ from this association. Does not destroy +records+. def delete(*records) records = flatten_deeper(records) records.each { |record| raise_on_type_mismatch(record) } records.reject! { |record| @target.delete(record) if record.new_record? } return if records.empty? @owner.transaction do records.each { |record| callback(:before_remove, record) } delete_records(records) records.each do |record| @target.delete(record) callback(:after_remove, record) end end end # Removes all records from this association. Returns +self+ so method calls may be chained. def clear return self if length.zero? # forces load_target if hasn't happened already if @reflection.options[:dependent] && @reflection.options[:dependent] == :delete_all destroy_all else delete_all end self end def destroy_all @owner.transaction do each { |record| record.destroy } end reset_target! end def create(attributes = {}) # Can't use Base.create since the foreign key may be a protected attribute. if attributes.is_a?(Array) attributes.collect { |attr| create(attr) } else record = build(attributes) record.save unless @owner.new_record? record end end # Returns the size of the collection by executing a SELECT COUNT(*) query if the collection hasn't been loaded and # calling collection.size if it has. If it's more likely than not that the collection does have a size larger than zero # and you need to fetch that collection afterwards, it'll take one less SELECT query if you use length. def size if loaded? && !@reflection.options[:uniq] @target.size elsif !loaded? && !@reflection.options[:uniq] && @target.is_a?(Array) unsaved_records = Array(@target.detect { |r| r.new_record? }) unsaved_records.size + count_records else count_records end end # Returns the size of the collection by loading it and calling size on the array. If you want to use this method to check # whether the collection is empty, use collection.length.zero? instead of collection.empty? def length load_target.size end def empty? size.zero? end def uniq(collection = self) seen = Set.new collection.inject([]) do |kept, record| unless seen.include?(record.id) kept << record seen << record.id end kept end end # Replace this collection with +other_array+ # This will perform a diff and delete/add only records that have changed. def replace(other_array) other_array.each { |val| raise_on_type_mismatch(val) } load_target other = other_array.size < 100 ? other_array : other_array.to_set current = @target.size < 100 ? @target : @target.to_set @owner.transaction do delete(@target.select { |v| !other.include?(v) }) concat(other_array.select { |v| !current.include?(v) }) end end protected def reset_target! @target = Array.new end def find_target records = if @reflection.options[:finder_sql] @reflection.klass.find_by_sql(@finder_sql) else find(:all) end @reflection.options[:uniq] ? uniq(records) : records end private def callback(method, record) callbacks_for(method).each do |callback| case callback when Symbol @owner.send(callback, record) when Proc, Method callback.call(@owner, record) else if callback.respond_to?(method) callback.send(method, @owner, record) else raise ActiveRecordError, "Callbacks must be a symbol denoting the method to call, a string to be evaluated, a block to be invoked, or an object responding to the callback method." end end end end def callbacks_for(callback_name) full_callback_name = "#{callback_name}_for_#{@reflection.name}" @owner.class.read_inheritable_attribute(full_callback_name.to_sym) || [] end end end end