1 files changed, 1 insertions, 1 deletions
diff --git a/enum.c b/enum.c
index b9d34d8c03..77ecd2fa56 100644
--- a/enum.c
+++ b/enum.c
@@ -901,7 +901,7 @@ enum_sort_by(VALUE obj)
 
     RETURN_ENUMERATOR(obj, 0, 0);
 
-    if (TYPE(obj) == T_ARRAY && RARRAY_LEN(obj) <= LONG_MAX/2) {
+    if (RB_TYPE_P(obj, T_ARRAY) && RARRAY_LEN(obj) <= LONG_MAX/2) {
 	ary = rb_ary_new2(RARRAY_LEN(obj)*2);
     }
     else {