From a5dda97602f2188a13cbcab5c7e9a5ba84ba876b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Valim?= <jose.valim@gmail.com>
Date: Mon, 5 Jul 2010 12:50:08 +0200
Subject: Define a convention for descendants and subclasses.

The former should be symmetric with ancestors and include all children. However, it should not include self since ancestors + descendants should not have duplicated. The latter is symmetric to superclass in the sense it only includes direct children.

By adopting a convention, we expect to have less conflict with other frameworks, as Datamapper. For this moment, to ensure ActiveModel::Validations can be used with Datamapper, we should always call ActiveSupport::DescendantsTracker.descendants(self) internally instead of self.descendants avoiding conflicts.
---
 .../active_support/core_ext/class/subclasses.rb    | 57 ++++++++++------------
 .../lib/active_support/core_ext/object.rb          |  1 -
 .../active_support/core_ext/object/extending.rb    | 11 -----
 3 files changed, 26 insertions(+), 43 deletions(-)
 delete mode 100644 activesupport/lib/active_support/core_ext/object/extending.rb

(limited to 'activesupport/lib/active_support/core_ext')

diff --git a/activesupport/lib/active_support/core_ext/class/subclasses.rb b/activesupport/lib/active_support/core_ext/class/subclasses.rb
index 7d58a8b56a..3e5d1a2a42 100644
--- a/activesupport/lib/active_support/core_ext/class/subclasses.rb
+++ b/activesupport/lib/active_support/core_ext/class/subclasses.rb
@@ -2,54 +2,49 @@ require 'active_support/core_ext/module/anonymous'
 require 'active_support/core_ext/module/reachable'
 
 class Class #:nodoc:
-  # Returns an array with the names of the subclasses of +self+ as strings.
-  #
-  #   Integer.subclasses # => ["Bignum", "Fixnum"]
-  def subclasses
-    Class.subclasses_of(self).map { |o| o.to_s }
-  end
-
   # Rubinius
   if defined?(Class.__subclasses__)
+    alias :subclasses :__subclasses__
+
     def descendants
-      subclasses = []
-      __subclasses__.each {|k| subclasses << k; subclasses.concat k.descendants }
-      subclasses
+      descendants = []
+      __subclasses__.each do |k|
+        descendants << k
+        descendants.concat k.descendants
+      end
+      descendants
     end
-  else
-    # MRI
+  else # MRI
     begin
       ObjectSpace.each_object(Class.new) {}
 
       def descendants
-        subclasses = []
+        descendants = []
         ObjectSpace.each_object(class << self; self; end) do |k|
-          subclasses << k unless k == self
+          descendants.unshift k unless k == self
         end
-        subclasses
+        descendants
       end
-    # JRuby
-    rescue StandardError
+    rescue StandardError # JRuby
       def descendants
-        subclasses = []
+        descendants = []
         ObjectSpace.each_object(Class) do |k|
-          subclasses << k if k < self
+          descendants.unshift k if k < self
         end
-        subclasses.uniq!
-        subclasses
+        descendants.uniq!
+        descendants
       end
     end
-  end
 
-  # Exclude this class unless it's a subclass of our supers and is defined.
-  # We check defined? in case we find a removed class that has yet to be
-  # garbage collected. This also fails for anonymous classes -- please
-  # submit a patch if you have a workaround.
-  def self.subclasses_of(*superclasses) #:nodoc:
-    subclasses = []
-    superclasses.each do |klass|
-      subclasses.concat klass.descendants.select {|k| k.anonymous? || k.reachable?}
+    # Returns an array with the direct children of +self+.
+    #
+    #   Integer.subclasses # => [Bignum, Fixnum]
+    def subclasses
+      subclasses, chain = [], descendants
+      chain.each do |k|
+        subclasses << k unless chain.any? { |c| c > k }
+      end
+      subclasses
     end
-    subclasses
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/object.rb b/activesupport/lib/active_support/core_ext/object.rb
index 8922016cd7..27618b55c6 100644
--- a/activesupport/lib/active_support/core_ext/object.rb
+++ b/activesupport/lib/active_support/core_ext/object.rb
@@ -6,7 +6,6 @@ require 'active_support/core_ext/object/try'
 require 'active_support/core_ext/object/conversions'
 require 'active_support/core_ext/object/instance_variables'
 require 'active_support/core_ext/object/misc'
-require 'active_support/core_ext/object/extending'
 
 require 'active_support/core_ext/object/returning'
 require 'active_support/core_ext/object/to_json'
diff --git a/activesupport/lib/active_support/core_ext/object/extending.rb b/activesupport/lib/active_support/core_ext/object/extending.rb
deleted file mode 100644
index c4c37b6a2a..0000000000
--- a/activesupport/lib/active_support/core_ext/object/extending.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-require 'active_support/core_ext/class/subclasses'
-
-class Object
-  # Exclude this class unless it's a subclass of our supers and is defined.
-  # We check defined? in case we find a removed class that has yet to be
-  # garbage collected. This also fails for anonymous classes -- please
-  # submit a patch if you have a workaround.
-  def subclasses_of(*superclasses) #:nodoc:
-    Class.subclasses_of(*superclasses)
-  end
-end
-- 
cgit v1.2.3