Do not destruct rest arguments for __send__

Formerly, `__send__(*args)` modified `args` with `Array#shift`.
This bug affects optcarrot.

This changeset avoids the array destruction by using
`args = args[1, len-1]`.

4 files changed, 15 insertions, 1 deletions

diff --git a/include/mruby/array.h b/include/mruby/array.h
index fd4094a02..92c86a8c5 100644
--- a/include/mruby/array.h
+++ b/include/mruby/array.h
@@ -292,6 +292,9 @@ MRB_API mrb_value mrb_ary_join(mrb_state *mrb, mrb_value ary, mrb_value sep);
  */
 MRB_API mrb_value mrb_ary_resize(mrb_state *mrb, mrb_value ary, mrb_int new_len);
 
+/* helper functions */
+mrb_value mrb_ary_subseq(mrb_state *mrb, mrb_value ary, mrb_int beg, mrb_int len);
+
 MRB_END_DECL
 
 #endif  /* MRUBY_ARRAY_H */
diff --git a/src/array.c b/src/array.c
index 6e73bcd8e..ad0d5b8db 100644
--- a/src/array.c
+++ b/src/array.c
@@ -808,6 +808,13 @@ ary_subseq(mrb_state *mrb, struct RArray *a, mrb_int beg, mrb_int len)
   return mrb_obj_value(b);
 }
 
+mrb_value
+mrb_ary_subseq(mrb_state *mrb, mrb_value ary, mrb_int beg, mrb_int len)
+{
+  struct RArray *a = mrb_ary_ptr(ary);
+  return ary_subseq(mrb, a, beg, len);
+}
+
 static mrb_int
 aget_index(mrb_state *mrb, mrb_value index)
 {
diff --git a/src/vm.c b/src/vm.c
index 7bb153910..bd54f3f00 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -625,7 +625,7 @@ mrb_f_send(mrb_state *mrb, mrb_value self)
     ci->argc--;
   }
   else {                     /* variable length arguments */
-    mrb_ary_shift(mrb, regs[0]);
+    regs[0] = mrb_ary_subseq(mrb, regs[0], 1, RARRAY_LEN(regs[0]) - 1);
   }
 
   if (MRB_METHOD_CFUNC_P(m)) {
diff --git a/test/t/kernel.rb b/test/t/kernel.rb
index aac6373fa..e3b9fe8ab 100644
--- a/test/t/kernel.rb
+++ b/test/t/kernel.rb
@@ -100,6 +100,10 @@ assert('Kernel#__send__', '15.3.1.3.4') do
   assert_true __send__(:respond_to?, :nil?)
   # test without argument and without block
   assert_equal String, __send__(:to_s).class
+
+  args = [:respond_to?, :nil?]
+  assert_true __send__(*args)
+  assert_equal [:respond_to?, :nil?], args
 end
 
 assert('Kernel#block_given?', '15.3.1.3.6') do