test_refinement.rb: Symbol#to_proc test

* test/ruby/test_refinement.rb (test_symbol_proc): a Symbol is
  converted to a Proc in the caller's context.  [Feature #9451]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56476 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/ruby/test_refinement.rb

@@ -101,6 +101,10 @@ class TestRefinement < Test::Unit::TestCase
       def self.invoke_call_x_on(foo)
         return foo.call_x
       end
+
+      def self.return_proc(&block)
+        block
+      end
     end
   end
 
@@ -1743,6 +1747,7 @@ class TestRefinement < Test::Unit::TestCase
 
   def test_symbol_proc
     assert_equal("FooExt#x", FooExtClient.map_x_on(Foo.new))
+    assert_equal("Foo#x", FooExtClient.return_proc(&:x).(Foo.new))
   end
 
   private