Warn instance variable `E`

It is not dumped, as it is a short alias for `:encoding`.

1 files changed, 6 insertions, 2 deletions

diff --git a/test/-ext-/marshal/test_internal_ivar.rb b/test/-ext-/marshal/test_internal_ivar.rb
index 51529667b5..a32138f6e8 100644
--- a/test/-ext-/marshal/test_internal_ivar.rb
+++ b/test/-ext-/marshal/test_internal_ivar.rb
@@ -7,14 +7,18 @@ module Bug end
 module Bug::Marshal
   class TestInternalIVar < Test::Unit::TestCase
     def test_marshal
-      v = InternalIVar.new("hello", "world")
+      v = InternalIVar.new("hello", "world", "bye")
       assert_equal("hello", v.normal)
       assert_equal("world", v.internal)
-      dump = ::Marshal.dump(v)
+      assert_equal("bye", v.encoding_short)
+      dump = assert_warn(/instance variable `E' on class \S+ is not dumped/) {
+        ::Marshal.dump(v)
+      }
       v = assert_nothing_raised {break ::Marshal.load(dump)}
       assert_instance_of(InternalIVar, v)
       assert_equal("hello", v.normal)
       assert_nil(v.internal)
+      assert_nil(v.encoding_short)
     end
   end
 end