Add optional argument to `Module#class_variables`.

mrbgems/mruby-metaprog/src/metaprog.c

@@ -697,7 +697,7 @@ mrb_mruby_metaprog_gem_init(mrb_state* mrb)
   mrb_define_method(mrb, krn, "define_singleton_method", mod_define_singleton_method, MRB_ARGS_ANY());
   mrb_define_method(mrb, krn, "send", mrb_f_send, MRB_ARGS_ANY()); /* 15.3.1.3.44 */
 
-  mrb_define_method(mrb, mod, "class_variables", mrb_mod_class_variables, MRB_ARGS_NONE()); /* 15.2.2.4.19 */
+  mrb_define_method(mrb, mod, "class_variables", mrb_mod_class_variables, MRB_ARGS_OPT(1)); /* 15.2.2.4.19 */
   mrb_define_method(mrb, mod, "remove_class_variable", mrb_mod_remove_cvar, MRB_ARGS_REQ(1)); /* 15.2.2.4.39 */
   mrb_define_method(mrb, mod, "class_variable_defined?", mrb_mod_cvar_defined, MRB_ARGS_REQ(1)); /* 15.2.2.4.16 */
   mrb_define_method(mrb, mod, "class_variable_get", mrb_mod_cvar_get, MRB_ARGS_REQ(1)); /* 15.2.2.4.17 */

src/variable.c

@@ -595,7 +595,7 @@ cv_i(mrb_state *mrb, mrb_sym sym, mrb_value v, void *p)
 /* 15.2.2.4.19 */
 /*
  *  call-seq:
- *     mod.class_variables   -> array
+ *     mod.class_variables(inherit=true)   -> array
  *
  *  Returns an array of the names of class variables in <i>mod</i>.
  *
@@ -613,11 +613,14 @@ mrb_mod_class_variables(mrb_state *mrb, mrb_value mod)
 {
   mrb_value ary;
   struct RClass *c;
+  mrb_bool inherit = TRUE;
 
+  mrb_get_args(mrb, "|b", &inherit);
   ary = mrb_ary_new(mrb);
   c = mrb_class_ptr(mod);
   while (c) {
     iv_foreach(mrb, c->iv, cv_i, &ary);
+    if (!inherit) break;
     c = c->super;
   }
   return ary;