Issue #11182 has been updated by Koichi Sasada.

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I can consider two models (1) and (2) the following pictures show.

![(1)](1.png)

![(2)](2.png)

I believe the implementation uses (2) model.

For (1), calling M::C#bar is reasonable.
For (2), calling M::C#bar is reasonable.

Wow, both should be M::C#bar.

Example on #5, both models should call M::C#bar. But my comment at #5 "C#bar should be same as C#foo" is wrong.


----------------------------------------
Bug #11182: Refinement with alias causes strange behavior
https://bugs.ruby-lang.org/issues/11182#change-52651

* Author: Koichi Sasada
* Status: Open
* Priority: Normal
* Assignee: Shugo Maeda
* ruby -v: 2.3dev
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
The following script causes strange behavior.

```ruby
class C
  def foo
    p "C"
  end
end

module M
  refine C do
    def foo
      p "Refiend C"
    end
  end
end

class D < C
  alias bar foo
end

using M
D.new.bar
#=> t.rb:21:in `<main>': undefined method `bar' for #<D:0x29fbf58> (NoMethodError)
```

It seems strange.

Maybe (1) C#foo or (2) M#C#foo should be called. But I'm not sure which is suitable.

Previous versions:

```
ruby 2.0.0p606 (2014-11-28 revision 48636) [i386-mswin32_110]
t.rb:9: warning: Refinements are experimental, and the behavior may change in future versions of Ruby!
"C"

ruby 2.1.5p312 (2015-03-10 revision 49912) [i386-mswin32_110]
"C"
```


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