Implement Kernel.local_variables for testing dumped local variables information.

mrbgems/mruby-proc-ext/src/proc.c

@@ -122,6 +122,29 @@ mrb_kernel_proc(mrb_state *mrb, mrb_value self)
   return blk;
 }
 
+static mrb_value
+mrb_local_variables(mrb_state *mrb, mrb_value self)
+{
+  mrb_value ret;
+  struct RProc *proc;
+  struct mrb_irep *irep;
+  size_t i;
+
+  proc = mrb->c->ci[-1].proc;
+
+  if (MRB_PROC_CFUNC_P(proc)) {
+    return mrb_ary_new(mrb);
+  }
+
+  irep = proc->body.irep;
+  ret = mrb_ary_new_capa(mrb, irep->lv_len);
+  for (i = 0; i < irep->lv_len; ++i) {
+    mrb_ary_push(mrb, ret, mrb_symbol_value(irep->lv[i].name));
+  }
+
+  return ret;
+}
+
 void
 mrb_mruby_proc_ext_gem_init(mrb_state* mrb)
 {
@@ -133,6 +156,7 @@ mrb_mruby_proc_ext_gem_init(mrb_state* mrb)
 
   mrb_define_class_method(mrb, mrb->kernel_module, "proc", mrb_kernel_proc, MRB_ARGS_NONE());
   mrb_define_method(mrb, mrb->kernel_module,       "proc", mrb_kernel_proc, MRB_ARGS_NONE());
+  mrb_define_module_function(mrb, mrb->kernel_module, "local_variables", mrb_local_variables, MRB_ARGS_NONE());
 }
 
 void

mrbgems/mruby-proc-ext/test/proc.rb

@@ -74,3 +74,11 @@ assert('mrb_cfunc_env_get') do
 
   assert_equal 1, t.get_int(1)
 end
+
+assert('Kernel.local_variables') do
+  a, b = 0, 1
+  a += b
+
+  vars = Kernel.local_variables.sort
+  assert_equal [:a, :b, :vars], vars
+end