diff options
Diffstat (limited to 'activerecord/lib/active_record/nested_attributes.rb')
| -rw-r--r-- | activerecord/lib/active_record/nested_attributes.rb | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/activerecord/lib/active_record/nested_attributes.rb b/activerecord/lib/active_record/nested_attributes.rb index 9e21039c4f..32a1dae6bc 100644 --- a/activerecord/lib/active_record/nested_attributes.rb +++ b/activerecord/lib/active_record/nested_attributes.rb @@ -248,10 +248,18 @@ module ActiveRecord # exception is raised. If omitted, any number associations can be processed. # Note that the :limit option is only applicable to one-to-many associations. # [:update_only] - # Allows you to specify that an existing record may only be updated. - # A new record may only be created when there is no existing record. - # This option only works for one-to-one associations and is ignored for - # collection associations. This option is off by default. + # For a one-to-one association, this option allows you to specify how + # nested attributes are to be used when an associated record already + # exists. In general, an existing record may either be updated with the + # new set of attribute values or be replaced by a wholly new record + # containing those values. By default the :update_only option is +false+ + # and the nested attributes are used to update the existing record only + # if they include the record's <tt>:id</tt> value. Otherwise a new + # record will be instantiated and used to replace the existing one. + # However if the :update_only option is +true+, the nested attributes + # are used to update the record's attributes always, regardless of + # whether the <tt>:id</tt> is present. The option is ignored for collection + # associations. # # Examples: # # creates avatar_attributes= @@ -280,7 +288,7 @@ module ActiveRecord # def pirate_attributes=(attributes) # assign_nested_attributes_for_one_to_one_association(:pirate, attributes, mass_assignment_options) # end - class_eval <<-eoruby, __FILE__, __LINE__ + 1 + generated_feature_methods.module_eval <<-eoruby, __FILE__, __LINE__ + 1 if method_defined?(:#{association_name}_attributes=) remove_method(:#{association_name}_attributes=) end @@ -312,10 +320,13 @@ module ActiveRecord # Assigns the given attributes to the association. # - # If update_only is false and the given attributes include an <tt>:id</tt> - # that matches the existing record's id, then the existing record will be - # modified. If update_only is true, a new record is only created when no - # object exists. Otherwise a new record will be built. + # If an associated record does not yet exist, one will be instantiated. If + # an associated record already exists, the method's behavior depends on + # the value of the update_only option. If update_only is +false+ and the + # given attributes include an <tt>:id</tt> that matches the existing record's + # id, then the existing record will be modified. If no <tt>:id</tt> is provided + # it will be replaced with a new record. If update_only is +true+ the existing + # record will be modified regardless of whether an <tt>:id</tt> is provided. # # If the given attributes include a matching <tt>:id</tt> attribute, or # update_only is true, and a <tt>:_destroy</tt> key set to a truthy value, |