diff options
Diffstat (limited to 'activerecord/lib/active_record/associations/through_association.rb')
| -rw-r--r-- | activerecord/lib/active_record/associations/through_association.rb | 110 |
1 files changed, 16 insertions, 94 deletions
diff --git a/activerecord/lib/active_record/associations/through_association.rb b/activerecord/lib/active_record/associations/through_association.rb index e1d60ccb17..e6ab628719 100644 --- a/activerecord/lib/active_record/associations/through_association.rb +++ b/activerecord/lib/active_record/associations/through_association.rb @@ -3,79 +3,24 @@ module ActiveRecord module Associations module ThroughAssociation #:nodoc: - delegate :source_options, :through_options, :source_reflection, :through_reflection, :to => :reflection + delegate :source_reflection, :through_reflection, :chain, :to => :reflection protected + # We merge in these scopes for two reasons: + # + # 1. To get the default_scope conditions for any of the other reflections in the chain + # 2. To get the type conditions for any STI models in the chain def target_scope - super.merge(through_reflection.klass.scoped) - end - - def association_scope - scope = super.joins(construct_joins) - scope = add_conditions(scope) - unless options[:include] - scope = scope.includes(source_options[:include]) + scope = super + chain[1..-1].each do |reflection| + scope = scope.merge(reflection.klass.scoped) end scope end private - # This scope affects the creation of the associated records (not the join records). At the - # moment we only support creating on a :through association when the source reflection is a - # belongs_to. Thus it's not necessary to set a foreign key on the associated record(s), so - # this scope has can legitimately be empty. - def creation_attributes - { } - end - - def aliased_through_table - name = through_reflection.table_name - - reflection.table_name == name ? - through_reflection.klass.arel_table.alias(name + "_join") : - through_reflection.klass.arel_table - end - - def construct_owner_conditions - super(aliased_through_table, through_reflection) - end - - def construct_joins - right = aliased_through_table - left = reflection.klass.arel_table - - conditions = [] - - if source_reflection.macro == :belongs_to - reflection_primary_key = source_reflection.association_primary_key - source_primary_key = source_reflection.foreign_key - - if options[:source_type] - column = source_reflection.foreign_type - conditions << - right[column].eq(options[:source_type]) - end - else - reflection_primary_key = source_reflection.foreign_key - source_primary_key = source_reflection.active_record_primary_key - - if source_options[:as] - column = "#{source_options[:as]}_type" - conditions << - left[column].eq(through_reflection.klass.name) - end - end - - conditions << - left[reflection_primary_key].eq(right[source_primary_key]) - - right.create_join( - right, - right.create_on(right.create_and(conditions))) - end - # Construct attributes for :through pointing to owner and associate. This is used by the # methods which create and delete records on the association. # @@ -112,37 +57,8 @@ module ActiveRecord end end - # The reason that we are operating directly on the scope here (rather than passing - # back some arel conditions to be added to the scope) is because scope.where([x, y]) - # has a different meaning to scope.where(x).where(y) - the first version might - # perform some substitution if x is a string. - def add_conditions(scope) - unless through_reflection.klass.descends_from_active_record? - scope = scope.where(through_reflection.klass.send(:type_condition)) - end - - scope = scope.where(interpolate(source_options[:conditions])) - scope.where(through_conditions) - end - - # If there is a hash of conditions then we make sure the keys are scoped to the - # through table name if left ambiguous. - def through_conditions - conditions = interpolate(through_options[:conditions]) - - if conditions.is_a?(Hash) - Hash[conditions.map { |key, value| - unless value.is_a?(Hash) || key.to_s.include?('.') - key = aliased_through_table.name + '.' + key.to_s - end - - [key, value] - }] - else - conditions - end - end - + # Note: this does not capture all cases, for example it would be crazy to try to + # properly support stale-checking for nested associations. def stale_state if through_reflection.macro == :belongs_to owner[through_reflection.foreign_key].to_s @@ -153,6 +69,12 @@ module ActiveRecord through_reflection.macro == :belongs_to && !owner[through_reflection.foreign_key].nil? end + + def ensure_not_nested + if reflection.nested? + raise HasManyThroughNestedAssociationsAreReadonly.new(owner, reflection) + end + end end end end |