File.basename returns frozen String

[jeremyevans]

A few of Roda's tests are failing on TruffleRuby because File.basename is returning a frozen string, while CRuby and JRuby return a new unfrozen string: https://github.com/jeremyevans/roda/runs/2492967121?check_suite_focus=true#step:4:17

Code in question:

            param_filename = File.basename(filename)
            encoding = param_filename.encoding

            needs_encoding = param_filename.gsub!(/[^ 0-9a-zA-Z!\#$&\+\.\^_`\|~]+/, '-') # FrozenError raised here

[eregon]

Thank you for the report!
It's probably a case where the argument is returned (no / in the given path), and the argument is a frozen String.

@bjfish Could you fix it?

[eregon]

Fixed in d2c8638