From: shugo@...
Date: 2015-12-17T01:23:40+00:00
Subject: [ruby-core:72197] [Ruby trunk - Bug #11826] [Assigned] After prepending a module, rewrite Hash#[] takes no effect for calls like Hash.new[:a]

Issue #11826 has been updated by Shugo Maeda.

Status changed from Open to Assigned
Assignee set to Koichi Sasada

cichol tsai wrote:
> It seems like an issue only for [] method, maybe something about syntax.
> But if use 'include' instead of 'prepend', the 'h[:a]' can give an output.
> Please help me check if it is a bug, sorry for bothering.

It seems that redefinition check of optimized methods doesn't work properly for prepended classes.
Is the following patch correct, ko1?

```diff
diff --git a/vm.c b/vm.c
index a03e068..cf528e8 100644
--- a/vm.c
+++ b/vm.c
@@ -1400,6 +1400,9 @@ static void
 rb_vm_check_redefinition_opt_method(const rb_method_entry_t *me, VALUE klass)
 {
     st_data_t bop;
+    if (RB_TYPE_P(klass, T_ICLASS) && FL_TEST(klass, RICLASS_IS_ORIGIN)) {
+	klass = RBASIC_CLASS(klass);
+    }
     if (me->def->type == VM_METHOD_TYPE_CFUNC) {
 	if (st_lookup(vm_opt_method_table, (st_data_t)me, &bop)) {
 	    int flag = vm_redefinition_check_flag(klass);
```


----------------------------------------
Bug #11826: After prepending a module, rewrite Hash#[] takes no effect for calls like Hash.new[:a]
https://bugs.ruby-lang.org/issues/11826#change-55609

* Author: cichol tsai
* Status: Assigned
* Priority: Normal
* Assignee: Koichi Sasada
* ruby -v: ruby 2.2.2p95 (2015-04-13 revision 50295) [x64-mingw32]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
~~~
module M
  def self.prepended(clz)
    clz.class_eval do
      def [](k)
        p 1
      end
    end
  end
end

module N
  def self.included(clz)
    clz.class_eval do 
      def []=(k, v)
        p 2
      end
    end
  end
end

class Hash
  prepend M
  include N
end

Hash.new[1]
Hash.new[1]=1
~~~

Running this example gives no output, which is expected to be '1 2'.
I am using 'ruby 2.2.2p95 (2015-04-13 revision 50295) [x64-mingw32]'.
Thanks in advanced.



-- 
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