From 56ccc7c73949e92b6c942a29076653e8a3e5eb55 Mon Sep 17 00:00:00 2001
From: Lourens Naude <lourens@methodmissing.com>
Date: Wed, 28 Jan 2009 17:10:24 +0000
Subject: [PATCH] Introduce Object#dup? to accommodate special case constants ( TrueClass, Fixnum etc. ) that do respond to #dup, but raises TypeError when invoked.

---
 .../active_support/cache/strategy/local_cache.rb   |    2 +-
 .../lib/active_support/core_ext/object/misc.rb     |   11 ++++++++++-
 .../test/core_ext/object_and_class_ext_test.rb     |   15 +++++++++++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/activesupport/lib/active_support/cache/strategy/local_cache.rb b/activesupport/lib/active_support/cache/strategy/local_cache.rb
index 621358d..761ab4d 100644
--- a/activesupport/lib/active_support/cache/strategy/local_cache.rb
+++ b/activesupport/lib/active_support/cache/strategy/local_cache.rb
@@ -41,7 +41,7 @@ module ActiveSupport
             value
           else
             # forcing the value to be immutable
-            value.dup
+            value.dup? ? value.dup : value
           end
         end
 
diff --git a/activesupport/lib/active_support/core_ext/object/misc.rb b/activesupport/lib/active_support/core_ext/object/misc.rb
index 4acdfa3..b8ff6bb 100644
--- a/activesupport/lib/active_support/core_ext/object/misc.rb
+++ b/activesupport/lib/active_support/core_ext/object/misc.rb
@@ -1,4 +1,7 @@
-class Object
+class Object  
+  
+  SPECIAL_CONSTANTS = [ TrueClass, FalseClass, NilClass, Symbol, Fixnum, BigDecimal, Float ]
+  
   # Returns +value+ after yielding +value+ to the block. This simplifies the
   # process of constructing an object, performing work on the object, and then
   # returning the object from a method. It is a Ruby-ized realization of the K
@@ -87,4 +90,10 @@ class Object
     respond_to? "acts_like_#{duck}?"
   end
 
+  # Identify if this object can be duped.Instances of NilClass, TrueClass, FalseClass 
+  # and Fixnum do respond to #dup, but raises a TypeError when called. 
+  def dup?
+    !SPECIAL_CONSTANTS.include?( self.class )
+  end
+
 end
diff --git a/activesupport/test/core_ext/object_and_class_ext_test.rb b/activesupport/test/core_ext/object_and_class_ext_test.rb
index 0bdbd14..3d97d68 100644
--- a/activesupport/test/core_ext/object_and_class_ext_test.rb
+++ b/activesupport/test/core_ext/object_and_class_ext_test.rb
@@ -280,3 +280,18 @@ class ObjectTryTest < Test::Unit::TestCase
     assert_equal 'false', false.try(:to_s)
   end
 end
+
+class ObjectDupTest < Test::Unit::TestCase
+  
+  def test_immuteable_objects_should_not_be_duped
+    assert !nil.dup?
+    assert !true.dup?
+    assert !false.dup?
+    assert !1.334.dup?
+    assert 12.dup?
+    assert !:symbol.dup?
+    assert 'string'.dup?
+    assert Class.new.dup?
+  end
+  
+end
-- 
1.5.4.5


From 7e3706b8650b7fc8fcba7d1b67f8395c6b347653 Mon Sep 17 00:00:00 2001
From: Lourens Naude <lourens@methodmissing.com>
Date: Wed, 28 Jan 2009 17:33:23 +0000
Subject: [PATCH] Alias Object#clone? to Object#dup?

---
 .../lib/active_support/core_ext/object/misc.rb     |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/activesupport/lib/active_support/core_ext/object/misc.rb b/activesupport/lib/active_support/core_ext/object/misc.rb
index b8ff6bb..4335ef8 100644
--- a/activesupport/lib/active_support/core_ext/object/misc.rb
+++ b/activesupport/lib/active_support/core_ext/object/misc.rb
@@ -95,5 +95,6 @@ class Object
   def dup?
     !SPECIAL_CONSTANTS.include?( self.class )
   end
+  alias :clone? :dup?
 
 end
-- 
1.5.4.5