object.c: singleton class clone

* object.c (rb_obj_clone): attach clone to its singleton class during
  cloning singleton class so that singleton_method_added will be called
  on it.  based on the patch by shiba (satoshi shiba)[Bug #5283] in
  [ruby-dev:44477].  [Bug #5283]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38648 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,10 @@
+Sat Dec 29 11:37:36 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* object.c (rb_obj_clone): attach clone to its singleton class during
+	  cloning singleton class so that singleton_method_added will be called
+	  on it.  based on the patch by shiba (satoshi shiba)[Bug #5283] in
+	  [ruby-dev:44477].  [Bug #5283]
+
 Sat Dec 29 10:10:39 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* configure.in (crt_externs.h): use standard macro AC_CHECK_HEADERS.

class.c

@@ -239,6 +239,12 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
 
 VALUE
 rb_singleton_class_clone(VALUE obj)
+{
+    return rb_singleton_class_clone_and_attach(obj, Qundef);
+}
+
+VALUE
+rb_singleton_class_clone_and_attach(VALUE obj, VALUE attach)
 {
     VALUE klass = RBASIC(obj)->klass;
 
@@ -264,6 +270,9 @@ rb_singleton_class_clone(VALUE obj)
 	    RCLASS_CONST_TBL(clone) = st_init_numtable();
 	    st_foreach(RCLASS_CONST_TBL(klass), clone_const_i, (st_data_t)RCLASS_CONST_TBL(clone));
 	}
+	if (attach != Qundef) {
+	    rb_singleton_class_attached(clone, attach);
+	}
 	RCLASS_M_TBL(clone) = st_init_numtable();
 	st_foreach(RCLASS_M_TBL(klass), clone_method_i, (st_data_t)clone);
 	rb_singleton_class_attached(RBASIC(clone)->klass, clone);

internal.h

@@ -63,6 +63,7 @@ VALUE rb_obj_private_methods(int argc, VALUE *argv, VALUE obj);
 VALUE rb_obj_public_methods(int argc, VALUE *argv, VALUE obj);
 int rb_obj_basic_to_s_p(VALUE);
 VALUE rb_special_singleton_class(VALUE);
+VALUE rb_singleton_class_clone_and_attach(VALUE obj, VALUE attach);
 void Init_class_hierarchy(void);
 
 /* compile.c */

object.c

@@ -298,7 +298,7 @@ rb_obj_clone(VALUE obj)
         rb_raise(rb_eTypeError, "can't clone %s", rb_obj_classname(obj));
     }
     clone = rb_obj_alloc(rb_obj_class(obj));
-    singleton = rb_singleton_class_clone(obj);
+    singleton = rb_singleton_class_clone_and_attach(obj, clone);
     RBASIC(clone)->klass = singleton;
     if (FL_TEST(singleton, FL_SINGLETON)) {
 	rb_singleton_class_attached(singleton, clone);

test/ruby/test_class.rb

@@ -336,4 +336,18 @@ class TestClass < Test::Unit::TestCase
       end;
     end
   end
+
+  def test_cloned_singleton_method_added
+    bug5283 = '[ruby-dev:44477]'
+    added = []
+    c = Class.new
+    c.singleton_class.class_eval do
+      define_method(:singleton_method_added) {|mid| added << [self, mid]}
+      def foo; :foo; end
+    end
+    added.clear
+    d = c.clone
+    assert_empty(added.grep(->(k) {c == k[0]}), bug5283)
+    assert_equal(:foo, d.foo)
+  end
 end