diff options
Diffstat (limited to 'activerecord/lib/active_record/reflection.rb')
-rw-r--r-- | activerecord/lib/active_record/reflection.rb | 59 |
1 files changed, 50 insertions, 9 deletions
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb index 5360db6a19..0394f89623 100644 --- a/activerecord/lib/active_record/reflection.rb +++ b/activerecord/lib/active_record/reflection.rb @@ -94,7 +94,8 @@ module ActiveRecord # @api public def reflect_on_all_associations(macro = nil) association_reflections = reflections.values - macro ? association_reflections.select { |reflection| reflection.macro == macro } : association_reflections + association_reflections.select! { |reflection| reflection.macro == macro } if macro + association_reflections end # Returns the AssociationReflection object for the +association+ (use the symbol). @@ -159,6 +160,54 @@ module ActiveRecord scope_chain.flatten end + def counter_cache_column + if belongs_to? + if options[:counter_cache] == true + "#{active_record.name.demodulize.underscore.pluralize}_count" + elsif options[:counter_cache] + options[:counter_cache].to_s + end + else + options[:counter_cache] ? options[:counter_cache].to_s : "#{name}_count" + end + end + + # This shit is nasty. We need to avoid the following situation: + # + # * An associated record is deleted via record.destroy + # * Hence the callbacks run, and they find a belongs_to on the record with a + # :counter_cache options which points back at our owner. So they update the + # counter cache. + # * In which case, we must make sure to *not* update the counter cache, or else + # it will be decremented twice. + # + # Hence this method. + def inverse_which_updates_counter_cache + return @inverse_which_updates_counter_cache if defined?(@inverse_which_updates_counter_cache) + @inverse_which_updates_counter_cache = klass.reflect_on_all_associations(:belongs_to).find do |inverse| + inverse.counter_cache_column == counter_cache_column + end + end + alias inverse_updates_counter_cache? inverse_which_updates_counter_cache + + def inverse_updates_counter_in_memory? + inverse_of && inverse_which_updates_counter_cache == inverse_of + end + + # Returns whether a counter cache should be used for this association. + # + # The counter_cache option must be given on either the owner or inverse + # association, and the column must be present on the owner. + def has_cached_counter? + options[:counter_cache] || + inverse_which_updates_counter_cache && inverse_which_updates_counter_cache.options[:counter_cache] && + !!active_record.columns_hash[counter_cache_column] + end + + def counter_must_be_updated_by_has_many? + !inverse_updates_counter_in_memory? && has_cached_counter? + end + def alias_candidate(name) "#{plural_name}_#{name}" end @@ -321,14 +370,6 @@ module ActiveRecord @active_record_primary_key ||= options[:primary_key] || primary_key(active_record) end - def counter_cache_column - if options[:counter_cache] == true - "#{active_record.name.demodulize.underscore.pluralize}_count" - elsif options[:counter_cache] - options[:counter_cache].to_s - end - end - def check_validity! check_validity_of_inverse! end |