check enc_capable.

* encoding.c (rb_enc_capable): make it extern to check enc_capable.
  enc_index can be set to limited types such as T_STRING, T_REGEX
  and so on. This function check an object is this kind of types.

* include/ruby/encoding.h: ditto.

* encoding.c (enc_set_index): check a given object is enc_capable.

* include/ruby/encoding.h (PUREFUNC):

* marshal.c (encoding_name): check `rb_enc_capable` first.

* marshal.c (r_ivar): ditto. If it is not enc_capable, it should be
  malformed data.

* spec/ruby/optional/capi/encoding_spec.rb: remove tests depending
  on the wrong feature: all objects can set enc_index.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63777 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 0 deletions

diff --git a/encoding.c b/encoding.c
index 9744c1d692..8d1894aa91 100644
--- a/encoding.c
+++ b/encoding.c
@@ -756,6 +756,12 @@ enc_capable(VALUE obj)
     }
 }
 
+int
+rb_enc_capable(VALUE obj)
+{
+    return enc_capable(obj);
+}
+
 ID
 rb_id_encoding(void)
 {
@@ -813,6 +819,8 @@ rb_enc_get_index(VALUE obj)
 static void
 enc_set_index(VALUE obj, int idx)
 {
+    if (!enc_capable(obj)) rb_bug("enc_set_index: not capable object");
+
     if (idx < ENCODING_INLINE_MAX) {
 	ENCODING_SET_INLINED(obj, idx);
 	return;