Change callbacks to automatically include DescendantsTracker and rename descendents to descendants.

1 files changed, 7 insertions, 3 deletions

diff --git a/activesupport/lib/active_support/callbacks.rb b/activesupport/lib/active_support/callbacks.rb
index 3ff33eea72..c4e1eb2c04 100644
--- a/activesupport/lib/active_support/callbacks.rb
+++ b/activesupport/lib/active_support/callbacks.rb
@@ -1,6 +1,6 @@
+require 'active_support/descendants_tracker'
 require 'active_support/core_ext/array/wrap'
 require 'active_support/core_ext/class/inheritable_attributes'
-require 'active_support/core_ext/class/subclasses'
 require 'active_support/core_ext/kernel/reporting'
 require 'active_support/core_ext/kernel/singleton_class'
 
@@ -85,6 +85,10 @@ module ActiveSupport
   module Callbacks
     extend Concern
 
+    included do
+      extend ActiveSupport::DescendantsTracker
+    end
+
     def run_callbacks(kind, *args, &block)
       send("_run_#{kind}_callbacks", *args, &block)
     end
@@ -428,7 +432,7 @@ module ActiveSupport
         options = filters.last.is_a?(Hash) ? filters.pop : {}
         filters.unshift(block) if block
 
-        ([self] + self.descendents).each do |target|
+        ([self] + self.descendants).each do |target|
           chain = target.send("_#{name}_callbacks")
           yield chain, type, filters, options
           target.__define_runner(name)
@@ -502,7 +506,7 @@ module ActiveSupport
       def reset_callbacks(symbol)
         callbacks = send("_#{symbol}_callbacks")
 
-        self.descendents.each do |target|
+        self.descendants.each do |target|
           chain = target.send("_#{symbol}_callbacks")
           callbacks.each { |c| chain.delete(c) }
           target.__define_runner(symbol)