Isolate the test for Encoding#replicate

It has global side effect which cannot be reverted.

1 files changed, 2 insertions, 0 deletions

diff --git a/test/ruby/test_encoding.rb b/test/ruby/test_encoding.rb
index 024d21b4f3..282ac6b1ae 100644
--- a/test/ruby/test_encoding.rb
+++ b/test/ruby/test_encoding.rb
@@ -56,11 +56,13 @@ class TestEncoding < Test::Unit::TestCase
   end
 
   def test_replicate
+    assert_separately([], "#{<<~'END;'}")
     assert_instance_of(Encoding, Encoding::UTF_8.replicate("UTF-8-ANOTHER#{Time.now.to_f}"))
     assert_instance_of(Encoding, Encoding::ISO_2022_JP.replicate("ISO-2022-JP-ANOTHER#{Time.now.to_f}"))
     bug3127 = '[ruby-dev:40954]'
     assert_raise(TypeError, bug3127) {Encoding::UTF_8.replicate(0)}
     assert_raise(ArgumentError, bug3127) {Encoding::UTF_8.replicate("\0")}
+    END;
   end
 
   def test_dummy_p