eval.c: fix message as same as previous versions

* eval.c (rb_frozen_class_p): fix message for singleton class of
  class/module as same as previous versions.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47568 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 5 insertions, 1 deletions

diff --git a/test/ruby/test_class.rb b/test/ruby/test_class.rb
index 9a4cdb0f58..7259594f8e 100644
--- a/test/ruby/test_class.rb
+++ b/test/ruby/test_class.rb
@@ -389,8 +389,12 @@ class TestClass < Test::Unit::TestCase
     obj = Object.new
     c = obj.singleton_class
     obj.freeze
-    assert_raise(RuntimeError, /frozen object/) {
+    assert_raise_with_message(RuntimeError, /frozen object/) {
       c.class_eval {def f; end}
     }
+    c = Class.new.freeze
+    assert_raise_with_message(RuntimeError, /frozen Class/) {
+      def c.f; end
+    }
   end
 end