proc.c: skip prepended modules

* proc.c (method_super_method): skip prepended modules and
  continue from the super class of the original class.
  [ruby-core:81666] [Bug #13656]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59080 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

proc.c

@@ -2652,7 +2652,7 @@ method_super_method(VALUE method)
     const rb_method_entry_t *me;
 
     TypedData_Get_Struct(method, struct METHOD, &method_data_type, data);
-    super_class = RCLASS_SUPER(method_entry_defined_class(data->me));
+    super_class = RCLASS_SUPER(RCLASS_ORIGIN(method_entry_defined_class(data->me)));
     if (!super_class) return Qnil;
     me = (rb_method_entry_t *)rb_callable_method_entry_without_refinements(super_class, data->me->called_id);
     if (!me) return Qnil;

test/ruby/test_method.rb

@@ -901,6 +901,17 @@ class TestMethod < Test::Unit::TestCase
     assert_nil(m)
   end
 
+  def test_super_method_with_prepended_module
+    bug = '[ruby-core:81666] [Bug #13656]'
+    c1 = EnvUtil.labeled_class("C1") {def m; end}
+    c2 = EnvUtil.labeled_class("C2", c1) {def m; end}
+    c2.prepend(EnvUtil.labeled_module("M"))
+    m = c2.instance_method(:m)
+    assert_equal(c2, m.owner)
+    m = m.super_method
+    assert_equal(c1, m.owner, bug)
+  end
+
   def rest_parameter(*rest)
     rest
   end