[ruby-core:99359] [Ruby master Bug#17007] SystemStackError when using super inside Module included and lexically inside refinement

[eregontp@gmail.com]

Issue #17007 has been updated by Eregon (Benoit Daloze).


Thanks for the fix!
BTW this changes the behavior on a new spec, is that intended? (result is [:A, :C] instead of [:A, :LOCAL, :C] on < 2.8)
https://github.com/ruby/spec/commit/b0da11b52560860e844470d145acee0ff4d4acea?w=1

----------------------------------------
Bug #17007: SystemStackError when using super inside Module included and lexically inside refinement
https://bugs.ruby-lang.org/issues/17007#change-86759

* Author: Eregon (Benoit Daloze)
* Status: Closed
* Priority: Normal
* Assignee: shugo (Shugo Maeda)
* ruby -v: ruby 2.7.1p83 (2020-03-31 revision a0c7c23c9c) [x86_64-linux]
* Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN
----------------------------------------
```ruby
class C
  def foo
    ["C"]
  end
end

refinement = Module.new do
  R = refine C do
    def foo
      ["R"] + super
    end

    include Module.new {
      def foo
        ["M"] + super
      end
    }
  end
end

using refinement
p C.new.foo
```

gives

```
$ ruby bug_refine_super.rb
Traceback (most recent call last):
	10920: from bug_refine_super.rb:22:in `<main>'
	10919: from bug_refine_super.rb:10:in `foo'
	10918: from bug_refine_super.rb:15:in `foo'
	10917: from bug_refine_super.rb:10:in `foo'
	10916: from bug_refine_super.rb:15:in `foo'
	10915: from bug_refine_super.rb:10:in `foo'
	10914: from bug_refine_super.rb:15:in `foo'
	10913: from bug_refine_super.rb:10:in `foo'
	 ... 10908 levels...
	    4: from bug_refine_super.rb:15:in `foo'
	    3: from bug_refine_super.rb:10:in `foo'
	    2: from bug_refine_super.rb:15:in `foo'
	    1: from bug_refine_super.rb:10:in `foo'
bug_refine_super.rb:15:in `foo': stack level too deep (SystemStackError)
```

OTOH defining the module lexically outside of `refine` works:
```ruby
m = Module.new {
  def foo
    ["M"] + super
  end
}
refinement = Module.new do
  R = refine C do
    def foo
      ["R"] + super
    end

    include m
  end
end

# result: ["R", "M", "C"]
```



-- 
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