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

1 files changed, 19 insertions, 0 deletions

diff --git a/test/ruby/test_module.rb b/test/ruby/test_module.rb
index b5e128ba3c..af626e5f47 100644
--- a/test/ruby/test_module.rb
+++ b/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]'