1 files changed, 51 insertions, 29 deletions
diff --git a/eval.c b/eval.c
index 6ee99359f9..f845bf98ae 100644
--- a/eval.c
+++ b/eval.c
@@ -1192,6 +1192,8 @@ rb_mod_append_features(VALUE module, VALUE include)
     return module;
 }
 
+static VALUE refinement_import_methods(int argc, VALUE *argv, VALUE refinement);
+
 /*
  *  call-seq:
  *     include(module, ...)    -> self
@@ -1345,9 +1347,9 @@ rb_using_refinement(rb_cref_t *cref, VALUE klass, VALUE module)
     }
     superclass = refinement_superclass(superclass);
     c = iclass = rb_include_class_new(module, superclass);
-    RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
+    RCLASS_SET_REFINED_CLASS(c, klass);
 
-    RCLASS_M_TBL(c) = RCLASS_M_TBL(module);
+    RCLASS_WRITE_M_TBL(c, RCLASS_M_TBL(module));
 
     rb_hash_aset(CREF_REFINEMENTS(cref), klass, iclass);
 }
@@ -1402,6 +1404,12 @@ rb_using_module(const rb_cref_t *cref, VALUE module)
     rb_clear_all_refinement_method_cache();
 }
 
+void
+rb_vm_using_module(VALUE module)
+{
+    rb_using_module(rb_vm_cref_replace_with_duplicated_cref(), module);
+}
+
 /*
  *  call-seq:
  *     target    -> class_or_module
@@ -1442,43 +1450,24 @@ add_activated_refinement(VALUE activated_refinements,
     }
     superclass = refinement_superclass(superclass);
     c = iclass = rb_include_class_new(refinement, superclass);
-    RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
+    RCLASS_SET_REFINED_CLASS(c, klass);
     refinement = RCLASS_SUPER(refinement);
     while (refinement && refinement != klass) {
-        c = RCLASS_SET_SUPER(c, rb_include_class_new(refinement, RCLASS_SUPER(c)));
-        RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
+        c = rb_class_set_super(c, rb_include_class_new(refinement, RCLASS_SUPER(c)));
+        RCLASS_SET_REFINED_CLASS(c, klass);
         refinement = RCLASS_SUPER(refinement);
     }
     rb_hash_aset(activated_refinements, klass, iclass);
 }
 
-/*
- *  call-seq:
- *     refine(mod) { block }   -> module
- *
- *  Refine <i>mod</i> in the receiver.
- *
- *  Returns a module, where refined methods are defined.
- */
-
-static VALUE
-rb_mod_refine(VALUE module, VALUE klass)
+void
+rb_refinement_setup(struct rb_refinements_data *data, VALUE module, VALUE klass)
 {
     VALUE refinement;
     ID id_refinements, id_activated_refinements,
        id_refined_class, id_defined_at;
     VALUE refinements, activated_refinements;
-    rb_thread_t *th = GET_THREAD();
-    VALUE block_handler = rb_vm_frame_block_handler(th->ec->cfp);
-
-    if (block_handler == VM_BLOCK_HANDLER_NONE) {
-        rb_raise(rb_eArgError, "no block given");
-    }
-    if (vm_block_handler_type(block_handler) != block_handler_type_iseq) {
-        rb_raise(rb_eArgError, "can't pass a Proc as a block to Module#refine");
-    }
 
-    ensure_class_or_module(klass);
     CONST_ID(id_refinements, "__refinements__");
     refinements = rb_attr_get(module, id_refinements);
     if (NIL_P(refinements)) {
@@ -1496,7 +1485,7 @@ rb_mod_refine(VALUE module, VALUE klass)
     if (NIL_P(refinement)) {
         VALUE superclass = refinement_superclass(klass);
         refinement = rb_refinement_new();
-        RCLASS_SET_SUPER(refinement, superclass);
+        rb_class_set_super(refinement, superclass);
         RUBY_ASSERT(BUILTIN_TYPE(refinement) == T_MODULE);
         FL_SET(refinement, RMODULE_IS_REFINEMENT);
         CONST_ID(id_refined_class, "__refined_class__");
@@ -1506,8 +1495,41 @@ rb_mod_refine(VALUE module, VALUE klass)
         rb_hash_aset(refinements, klass, refinement);
         add_activated_refinement(activated_refinements, klass, refinement);
     }
-    rb_yield_refine_block(refinement, activated_refinements);
-    return refinement;
+
+    data->refinement = refinement;
+    data->refinements = activated_refinements;
+}
+
+/*
+ *  call-seq:
+ *     refine(mod) { block }   -> module
+ *
+ *  Refine <i>mod</i> in the receiver.
+ *
+ *  Returns a module, where refined methods are defined.
+ */
+
+static VALUE
+rb_mod_refine(VALUE module, VALUE klass)
+{
+    /* module is the receiver of #refine, klass is a module to be refined (`mod` in the doc) */
+    rb_thread_t *th = GET_THREAD();
+    VALUE block_handler = rb_vm_frame_block_handler(th->ec->cfp);
+    struct rb_refinements_data data;
+
+    if (block_handler == VM_BLOCK_HANDLER_NONE) {
+        rb_raise(rb_eArgError, "no block given");
+    }
+    if (vm_block_handler_type(block_handler) != block_handler_type_iseq) {
+        rb_raise(rb_eArgError, "can't pass a Proc as a block to Module#refine");
+    }
+
+    ensure_class_or_module(klass);
+
+    rb_refinement_setup(&data, module, klass);
+
+    rb_yield_refine_block(data.refinement, data.refinements);
+    return data.refinement;
 }
 
 static void