Issue #14232 has been updated by nagachika (Tomoyuki Chikanaga).

Backport changed from 2.3: REQUIRED, 2.4: REQUIRED, 2.5: REQUIRED to 2.3: DONTNEED, 2.4: REQUIRED, 2.5: REQUIRED

You cannot refine Module on 2.3.x.
I set DONTNEED for 2.3.

----------------------------------------
Bug #14232: Unused refinement still breaks method search
https://bugs.ruby-lang.org/issues/14232#change-69623

* Author: shugo (Shugo Maeda)
* Status: Closed
* Priority: Normal
* Assignee: shugo (Shugo Maeda)
* Target version: 
* ruby -v: 
* Backport: 2.3: DONTNEED, 2.4: REQUIRED, 2.5: REQUIRED
----------------------------------------
Given the following t.rb:

```
module A
  def foo
    puts "A#foo"
    super
  end
end

class B
  def foo
    puts "B#foo"
  end
end

class C < B
  include A

  def foo
    puts "C#foo"
    super
  end
end

module D
  refine A do
    def foo
    end
  end
end

C.new.foo
```

Even if D is not used, B#foo cannot be called by super in A#foo:

```
$ ruby t.rb
C#foo
A#foo
Traceback (most recent call last):
        2: from t.rb:30:in `<main>'
        1: from t.rb:19:in `foo'
t.rb:4:in `foo': super: no superclass method `foo' for #<C:0x00005623950b74f8> (NoMethodError)
```




-- 
https://bugs.ruby-lang.org/