`Racc::ParseError` on argument forwarding with `(...)`

[spickermann]

I noticed that the duplication check generates Racc::ParseError log messages about parsing errors on ....

I, [2023-03-21T10:07:19.656114 #1]  INFO -- : Skipping file ./example.rb due to exception (Racc::ParseError): ./example.rb:5 :: parse error on value "..." (tDOT3)

The file basically looks like this:

module Callable
  extend ActiveSupport::Concern

  class_methods do
    def call(...)
      new(...).call
    end

    def call!(...)
      new(...).call!
    end
  end
end

I wonder why the parser fails to parse this, because that syntax was introduced in Ruby 2.7 already. And I wonder if this issue is related to https://github.com/codeclimate/codeclimate-duplication/issues/375 because in that issue the parser is also failing to parse a newer language feature.

What version of Ruby (and thereby what version of the Racc Parser) does CodeClimate use to run the duplication check?