thanks

This kata is mostly broken and abandoned (see the high number of open issues). So, to answer your question: is that normal? Not really, ideally. But it probably won't be fixed for a while, there are more urgent problems.

Though, I don' think it rejects a correct answer, but I am not sure either. You should try to print the input by yourself (println!("{:?}",self.data); inside is_valid).

the Kata passes when I click test, but fails on clicking attempt.
the error messages doesn't show me which test cases fail, is that normal ?

trying it in rust