merge revision(s) 60980,60984: [Backport #14070]

	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]

	The superclass of a refinement should have BasicObject as its ancestor.

	Otherwise, VM_ASSERT(callable_method_entry_p(cme)) in
	prepare_callable_method_entry() fails if VM_CHECK_MODE is 2.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@62233 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 19 insertions, 0 deletions

diff --git a/test/ruby/test_refinement.rb b/test/ruby/test_refinement.rb
index ba7691335f..881146cfe0 100644
--- a/test/ruby/test_refinement.rb
+++ b/test/ruby/test_refinement.rb
@@ -1961,6 +1961,25 @@ class TestRefinement < Test::Unit::TestCase
     end
   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)