fails:String#unpack with format 'V' ignores whitespace in the format string
fails:String#unpack with format 'V' calls #to_str to coerce the directives string
fails:String#unpack with format 'V' adds nil for each element requested beyond the end of the String
fails:String#unpack with format 'v' calls #to_str to coerce the directives string
fails:String#unpack with format 'v' adds nil for each element requested beyond the end of the String
