io.c: preserve encodings

* io.c (advice_arg_check): preserve encodings in warning messages.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47303 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

io.c

@@ -8558,9 +8558,7 @@ advice_arg_check(VALUE advice)
 	advice != sym_willneed &&
 	advice != sym_dontneed &&
 	advice != sym_noreuse) {
-	VALUE symname = rb_inspect(advice);
-	rb_raise(rb_eNotImpError, "Unsupported advice: %s",
-		 StringValuePtr(symname));
+	rb_raise(rb_eNotImpError, "Unsupported advice: %+"PRIsVALUE, advice);
     }
 }
 

test/ruby/test_io.rb

@@ -2476,10 +2476,10 @@ End
   def test_invalid_advise
     feature4204 = '[ruby-dev:42887]'
     make_tempfile {|tf|
-      %w{Normal rand glark will_need zzzzzzzzzzzz \u2609}.map(&:to_sym).each do |adv|
+      %W{Normal rand glark will_need zzzzzzzzzzzz \u2609}.map(&:to_sym).each do |adv|
         [[0,0], [0, 20], [400, 2]].each do |offset, len|
           open(tf.path) do |t|
-            assert_raise(NotImplementedError, feature4204) { t.advise(adv, offset, len) }
+            assert_raise_with_message(NotImplementedError, /#{adv.inspect}/, feature4204) { t.advise(adv, offset, len) }
           end
         end
       end