Modules should not have subclasses.

When refining a module, the module was set to the superclass of its refinement,
and a segmentation fault occurred.
The superclass of the refinement should be an iclass of the module.
[ruby-core:83617] [Bug #14070]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60980 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

eval.c

@@ -1304,6 +1304,10 @@ rb_using_refinement(rb_cref_t *cref, VALUE klass, VALUE module)
 	}
     }
     FL_SET(module, RMODULE_IS_OVERLAID);
+    if (RB_TYPE_P(superclass, T_MODULE)) {
+	superclass = rb_include_class_new(superclass,
+					  RCLASS_SUPER(superclass));
+    }
     c = iclass = rb_include_class_new(module, superclass);
     RCLASS_REFINED_CLASS(c) = klass;
 
@@ -1398,6 +1402,10 @@ add_activated_refinement(VALUE activated_refinements,
 	}
     }
     FL_SET(refinement, RMODULE_IS_OVERLAID);
+    if (RB_TYPE_P(superclass, T_MODULE)) {
+	superclass = rb_include_class_new(superclass,
+					  RCLASS_SUPER(superclass));
+    }
     c = iclass = rb_include_class_new(refinement, superclass);
     RCLASS_REFINED_CLASS(c) = klass;
     refinement = RCLASS_SUPER(refinement);
@@ -1453,7 +1461,12 @@ rb_mod_refine(VALUE module, VALUE klass)
     refinement = rb_hash_lookup(refinements, klass);
     if (NIL_P(refinement)) {
 	refinement = rb_module_new();
-	RCLASS_SET_SUPER(refinement, klass);
+	if (RB_TYPE_P(klass, T_MODULE)) {
+	    rb_include_module(refinement, klass);
+	}
+	else {
+	    RCLASS_SET_SUPER(refinement, klass);
+	}
 	FL_SET(refinement, RMODULE_IS_REFINEMENT);
 	CONST_ID(id_refined_class, "__refined_class__");
 	rb_ivar_set(refinement, id_refined_class, klass);

test/ruby/test_refinement.rb

@@ -2036,6 +2036,25 @@ class TestRefinement < Test::Unit::TestCase
     INPUT
   end
 
+  def test_refining_module_repeatedly
+    bug14070 = '[ruby-core:83617] [Bug #14070]'
+    assert_in_out_err([], <<-INPUT, ["ok"], [], bug14070)
+      1000.times do
+        Class.new do
+          include Enumerable
+        end
+
+        Module.new do
+          refine Enumerable do
+            def foo
+            end
+          end
+        end
+      end
+      puts "ok"
+    INPUT
+  end
+
   private
 
   def eval_using(mod, s)