diff options
Diffstat (limited to 'activerecord/lib/active_record/associations/has_many_through_association.rb')
-rw-r--r-- | activerecord/lib/active_record/associations/has_many_through_association.rb | 55 |
1 files changed, 31 insertions, 24 deletions
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb index 73baefb8e1..175019a72b 100644 --- a/activerecord/lib/active_record/associations/has_many_through_association.rb +++ b/activerecord/lib/active_record/associations/has_many_through_association.rb @@ -12,17 +12,18 @@ module ActiveRecord @through_association = nil 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 fewer - # SELECT query if you use #length. + # Returns the size of the collection by executing a SELECT COUNT(*) query + # if the collection hasn't been loaded, and by calling collection.size if + # it has. If the collection will likely have a size greater than zero, + # and if fetching the collection will be needed afterwards, one less + # SELECT query will be generated by using #length instead. def size if has_cached_counter? owner.read_attribute cached_counter_attribute_name(reflection) elsif loaded? target.size else - count + super end end @@ -72,25 +73,27 @@ module ActiveRecord @through_association ||= owner.association(through_reflection.name) end - # We temporarily cache through record that has been build, because if we build a - # through record in build_record and then subsequently call insert_record, then we - # want to use the exact same object. + # The through record (built with build_record) is temporarily cached + # so that it may be reused if insert_record is subsequently called. # - # However, after insert_record has been called, we clear the cache entry because - # we want it to be possible to have multiple instances of the same record in an - # association + # However, after insert_record has been called, the cache is cleared in + # order to allow multiple instances of the same record in an association. def build_through_record(record) @through_records[record.object_id] ||= begin ensure_mutable - through_record = through_association.build through_scope_attributes + through_record = through_association.build(*options_for_through_record) through_record.send("#{source_reflection.name}=", record) through_record end end + def options_for_through_record + [through_scope_attributes] + end + def through_scope_attributes - scope.where_values_hash(through_association.reflection.name.to_s) + scope.where_values_hash(through_association.reflection.name.to_s).except!(through_association.reflection.foreign_key) end def save_through_record(record) @@ -106,9 +109,9 @@ module ActiveRecord inverse = source_reflection.inverse_of if inverse - if inverse.macro == :has_many + if inverse.collection? record.send(inverse.name) << build_through_record(record) - elsif inverse.macro == :has_one + elsif inverse.has_one? record.send("#{inverse.name}=", build_through_record(record)) end end @@ -117,7 +120,7 @@ module ActiveRecord end def target_reflection_has_associated_record? - !(through_reflection.macro == :belongs_to && owner[through_reflection.foreign_key].blank?) + !(through_reflection.belongs_to? && owner[through_reflection.foreign_key].blank?) end def update_through_counter?(method) @@ -131,13 +134,13 @@ module ActiveRecord end end + def delete_or_nullify_all_records(method) + delete_records(load_target, method) + end + def delete_records(records, method) ensure_not_nested - # This is unoptimised; it will load all the target records - # even when we just want to delete everything. - records = load_target if records == :all - scope = through_association.scope scope.where! construct_join_attributes(*records) @@ -171,7 +174,7 @@ module ActiveRecord klass.decrement_counter counter, records.map(&:id) end - if through_reflection.macro == :has_many && update_through_counter?(method) + if through_reflection.collection? && update_through_counter?(method) update_counter(-count, through_reflection) end @@ -181,14 +184,18 @@ module ActiveRecord def through_records_for(record) attributes = construct_join_attributes(record) candidates = Array.wrap(through_association.target) - candidates.find_all { |c| c.attributes.slice(*attributes.keys) == attributes } + candidates.find_all do |c| + attributes.all? do |key, value| + c.public_send(key) == value + end + end end def delete_through_records(records) records.each do |record| through_records = through_records_for(record) - if through_reflection.macro == :has_many + if through_reflection.collection? through_records.each { |r| through_association.target.delete(r) } else if through_records.include?(through_association.target) @@ -202,7 +209,7 @@ module ActiveRecord def find_target return [] unless target_reflection_has_associated_record? - scope.to_a + get_records end # NOTE - not sure that we can actually cope with inverses here |