Fix and refine error message in `mrb_obj_to_sym()`
Before this patch:
$ bin/mruby -e '1.respond_to?(2)'  #=> nil is not a symbol
After this patch (same as Ruby):
$ bin/mruby -e '1.respond_to?(2)'  #=> 2 is not a symbol nor a string
MODIFY
src/etc.c
src/etc.c
@@ -65,24 +65,10 @@ mrb_data_get_ptr(mrb_state *mrb, mrb_value obj, const mrb_data_type *type)
MRB_API mrb_sym
mrb_obj_to_sym(mrb_state *mrb, mrb_value name)
{
- mrb_sym id;
-
- switch (mrb_type(name)) {
- default:
- name = mrb_check_string_type(mrb, name);
- if (mrb_nil_p(name)) {
- name = mrb_inspect(mrb, name);
- mrb_raisef(mrb, E_TYPE_ERROR, "%S is not a symbol", name);
- /* not reached */
- }
- /* fall through */
- case MRB_TT_STRING:
- name = mrb_str_intern(mrb, name);
- /* fall through */
- case MRB_TT_SYMBOL:
- id = mrb_symbol(name);
- }
- return id;
+ if (mrb_symbol_p(name)) return mrb_symbol(name);
+ if (mrb_string_p(name)) return mrb_intern_str(mrb, name);
+ mrb_raisef(mrb, E_TYPE_ERROR, "%S is not a symbol nor a string", mrb_inspect(mrb, name));
+ return 0; /* not reached */
}
MRB_API mrb_int

Fix and refine error message in `mrb_obj_to_sym()`

Before this patch:

  $ bin/mruby -e '1.respond_to?(2)'  #=> nil is not a symbol

After this patch (same as Ruby):

  $ bin/mruby -e '1.respond_to?(2)'  #=> 2 is not a symbol nor a string