cargo test panic

[BaldDemian]

5 test cases failed due to the char::to_digit call: to_digit: invalid radix -- radix must be in the range 2 to 36 inclusive.

I believe this is caused by the change of char::to_digit method after Rust 1.84.0.

rust-lang/rust@aeffff8

[BaldDemian]

For those who encountered the same problem, simply downgrade the Rust version to 1.83.0 in this project by running:
rustup install 1.83.0 and rustup override set 1.83.0