vm_insnhelper.c: fix zsuper in prepended

* vm_insnhelper.c (vm_call_method): a method entry refers the based
  class/module, so should search superclass from the origin i-class
  where the entry belongs to, to get rid of infinite loop when zsuper
  in a prepended class/module.  [ruby-core:54105] [Bug #8238]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42724 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 15 insertions, 0 deletions

diff --git a/test/ruby/test_module.rb b/test/ruby/test_module.rb
index 1124101664..7d5eb99ff0 100644
--- a/test/ruby/test_module.rb
+++ b/test/ruby/test_module.rb
@@ -1527,6 +1527,21 @@ class TestModule < Test::Unit::TestCase
     assert_nothing_raised(NoMethodError, bug8005) {a.send :foo}
   end
 
+  def test_prepend_visibility_inherited
+    bug8238 = '[ruby-core:54105] [Bug #8238]'
+    assert_separately [], <<-"end;", timeout: 3
+      class A
+        def foo() A; end
+        private :foo
+      end
+      class B < A
+        public :foo
+        prepend Module.new
+      end
+      assert_equal(A, B.new.foo, "#{bug8238}")
+    end;
+  end
+
   def test_prepend_included_modules
     bug8025 = '[ruby-core:53158] [Bug #8025]'
     mixin = labeled_module("mixin")