[Fix #9011] Mark Lint/Loop as unsafe

[dvandersluis]

The case in #9011

loop do
  key = generate_key
  break if some_check?
end

puts key

cannot be detected by static analysis, so instead I've marked autocorrection for Lint/Loop as unsafe and added an explanation.

---

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[marcandre]

cannot be detected by static analysis

Are you sure?

Also, like I wrote in #9008, loop rescues StopIteration, so it's never strictly equivalent.

[dvandersluis]

@marcandre I was simplifying, we could I suppose detect every lvar in the begin and look for it in the following code but there are always edge cases and I don’t think it’s worthwhile.

Didn’t know about StopIteration but then that’s another reason to make it unsafe. I can change it to be unsafe as a whole and not just for autocorrection.

[marcandre]

I can change it to be unsafe as a whole and not just for autocorrection.

Probably the most accurate thing to do, however unlikely it is to affect someone.

[dvandersluis]

Updated!

[marcandre]

Thanks!