class.c: always clear tables first

* class.c (rb_mod_init_copy): always clear instance variable,
  constant and method tables first, regardless the source tables.
  [ruby-dev:48182] [Bug #9813]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45874 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Thu May  8 14:34:29 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* class.c (rb_mod_init_copy): always clear instance variable,
+	  constant and method tables first, regardless the source tables.
+	  [ruby-dev:48182] [Bug #9813]
+
 Thu May  8 10:53:14 2014  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* configure.in: OpenBSD needs to include sys/param.h before include

class.c

@@ -328,12 +328,21 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
     }
     RCLASS_SET_SUPER(clone, RCLASS_SUPER(orig));
     RCLASS_EXT(clone)->allocator = RCLASS_EXT(orig)->allocator;
+    if (RCLASS_IV_TBL(clone)) {
+	st_free_table(RCLASS_IV_TBL(clone));
+	RCLASS_IV_TBL(clone) = 0;
+    }
+    if (RCLASS_CONST_TBL(clone)) {
+	rb_free_const_table(RCLASS_CONST_TBL(clone));
+	RCLASS_CONST_TBL(clone) = 0;
+    }
+    if (RCLASS_M_TBL_WRAPPER(clone)) {
+	rb_free_m_tbl_wrapper(RCLASS_M_TBL_WRAPPER(clone));
+	RCLASS_M_TBL_WRAPPER(clone) = 0;
+    }
     if (RCLASS_IV_TBL(orig)) {
 	st_data_t id;
 
-	if (RCLASS_IV_TBL(clone)) {
-	    st_free_table(RCLASS_IV_TBL(clone));
-	}
 	RCLASS_IV_TBL(clone) = rb_st_copy(clone, RCLASS_IV_TBL(orig));
 	CONST_ID(id, "__tmp_classpath__");
 	st_delete(RCLASS_IV_TBL(clone), &id, 0);
@@ -344,18 +353,13 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
     }
     if (RCLASS_CONST_TBL(orig)) {
 	struct clone_const_arg arg;
-	if (RCLASS_CONST_TBL(clone)) {
-	    rb_free_const_table(RCLASS_CONST_TBL(clone));
-	}
+
 	RCLASS_CONST_TBL(clone) = st_init_numtable();
 	arg.klass = clone;
 	arg.tbl = RCLASS_CONST_TBL(clone);
 	st_foreach(RCLASS_CONST_TBL(orig), clone_const_i, (st_data_t)&arg);
     }
     if (RCLASS_M_TBL(orig)) {
-	if (RCLASS_M_TBL_WRAPPER(clone)) {
-	    rb_free_m_tbl_wrapper(RCLASS_M_TBL_WRAPPER(clone));
-	}
 	RCLASS_M_TBL_INIT(clone);
 	st_foreach(RCLASS_M_TBL(orig), clone_method_i, (st_data_t)clone);
     }

test/ruby/test_module.rb

@@ -375,6 +375,25 @@ class TestModule < Test::Unit::TestCase
     assert_equal(:ok, Object.new.extend(m).foo, bug9535)
   end
 
+  def test_initialize_copy_empty
+    bug9813 = '[ruby-dev:48182] [Bug #9813]'
+    m = Module.new do
+      def x
+      end
+      const_set(:X, 1)
+      @x = 2
+    end
+    assert_equal([:x], m.instance_methods)
+    assert_equal([:@x], m.instance_variables)
+    assert_equal([:X], m.constants)
+    m.module_eval do
+      initialize_copy(Module.new)
+    end
+    assert_empty(m.instance_methods, bug9813)
+    assert_empty(m.instance_variables, bug9813)
+    assert_empty(m.constants, bug9813)
+  end
+
   def test_dup
     bug6454 = '[ruby-core:45132]'