Is the Solution to Quiz 2 correct?

[sibkru]

I'm new to Rust, so I might be doing something wrong.

In Quiz 2, I was struggling with the following error:

pub fn transformer(input: Vec<(String, Command)>) -> Vec {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can't leak private type

The solution seems to be to make the Command Enum public.
pub enum Command { Uppercase, Trim, Append(usize), }
I wasn't sure if that was a hack or the correct way, so I looked into the solution, which does not declare the enum as public.
But when I copy and paste the solution and look at the rustlings output, I get the same error message I got with my own code (now also for transformer_iter).

rustlings version: 6.0.1
rustc version: 1.79
cargo version: 1.79

Is the solution incorrect, or am I doing something wrong on my side (probably the latter)?

[mo8it]

You are probably doing something wrong because the solutions are checked in the CI to all compile and run correctly.

Can you please paste your whole exercise code?

[sibkru]

// - Strings
// - Vecs
// - Move semantics
// - Modules
// - Enums
//
// Let's build a little machine in the form of a function. As input, we're going
// to give a list of strings and commands. These commands determine what action
// is going to be applied to the string. It can either be:
// - Uppercase the string
// - Trim the string
// - Append "bar" to the string a specified amount of times
//
// The exact form of this will be:
// - The input is going to be a Vector of 2-length tuples,
//   the first element is the string, the second one is the command.
// - The output element is going to be a vector of strings.

enum Command {
    Uppercase,
    Trim,
    Append(usize),
}

mod my_module {
    use super::Command;

    // TODO: Complete the function.
    // pub fn transformer(input: ???) -> ??? { ??? }
    pub fn transformer(input: Vec<(String, Command)>) -> Vec<String> {
        let mut result = vec![];
        for line in input.into_iter() {
            match line {
                (a, Command::Uppercase) => {
                    result.push(a.to_uppercase());
                }
                (a, Command::Trim) => {
                    result.push(a.trim().to_string());
                }
                (a, Command::Append(num)) => {
                    result.push(a + &"bar".repeat(num));
                }
            };
        }
        result
    }
}

fn main() {
    // You can optionally experiment here.
}

#[cfg(test)]
mod tests {
    // TODO: What do we need to import to have `transformer` in scope?
    // use ???;
    use super::my_module::transformer;
    use super::Command;

    #[test]
    fn it_works() {
        let input = vec![
            ("hello".to_string(), Command::Uppercase),
            (" all roads lead to rome! ".to_string(), Command::Trim),
            ("foo".to_string(), Command::Append(1)),
            ("bar".to_string(), Command::Append(5)),
        ];
        let output = transformer(input);

        assert_eq!(
            output,
            [
                "HELLO",
                "all roads lead to rome!",
                "foobar",
                "barbarbarbarbarbar",
            ]
        );
    }
}

This is my complete exercise code that yields the above-described error.
When I copy the transformer function from here: https://github.com/rust-lang/rustlings/blob/main/solutions/quizzes/quiz2.rs
I get the same error.

[mo8it]

I can't reproduce it. Very weird.

I also pasted it into the Rust playground and it ran without any problem: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=50188eeb2b80684521e1c7c73282c239

Are you sure cargo --version returns the version 1.79?

Can you please run rustup update and try again?

Can you please also share a screenshot of the error in Rustlings?

[sibkru]

That's really weird. How could I have broken my rust settings?

I also listed my installed toolchains, I only have
stable-aarch64-apple-darwin installed.

I also tried switching to a different exercise in Rustlings and back to test whether Rustlings did not update its error message for some reason, but the error appeared again.

Thank you for your help

[mo8it]

I just ran the checks in the CI on Apple. All solutions ran without a problem:
https://github.com/rust-lang/rustlings/actions/runs/9974536710/job/27562222308?pr=2052

Can you please create a new project with cargo new quiz2 in some directory, paste your code in #2045 (comment) and run it with cargo clippy and cargo test? Please also do the same with the solution file. This allows us to separate the problem from Rustlings.

[sibkru]

Here are the results:
on my exercise:
cargo clippy produces the same error.
cargo test runs fine.

on solution file:
cargo clippy produces the error.
cargo test runs fine.

[mo8it]

I asked for help on the Rust forum: https://users.rust-lang.org/t/error-only-on-a-specific-target/114552

[sibkru]

Thanks, I appreciate you taking the time!

[wezm]

cargo clippy produces the error.
cargo test runs fine.

@sibkru since it is clippy that is failing it might be worth including the output of:

which cargo-clippy

and

cargo clippy --version

as well.

[mo8it]

Oh, good idea! It is also worth trying out cargo check.

[mo8it]

@sibkru Did you find time to try the commands above? :)