cannot move out of `keymap.command` which is behind a shared reference

The following is a mock code for running a terminal command:

#[derive(Debug)]
pub struct Keymap {
    pub key: char,
    pub command: String,
}

impl Keymap {
    pub fn new<S: AsRef<str>>(key: char, command: S) -> Self {
        let command = command.as_ref().to_owned();

        Self {
            key,
            command,
        }
    }
}

fn handle_keymap(keymap: &Keymap) {
    println!("Do something with the keymap: {:?}", keymap);

    run_command(keymap.command);
}

fn run_command(command_string: String) {
    let command_string = command_string.replace("test", "best");

    println!("Running this command: {:?}", command_string);
}

fn main() {
    let keymap = vec![Keymap::new('t', "echo 'test'")].into_iter().next().unwrap();

    handle_keymap(&keymap);
}

Rust Playground

Right now, there's an error here:

error[E0507]: cannot move out of `keymap.command` which is behind a shared reference
  --> src/main.rs:21:17
   |
21 |     run_command(keymap.command);
   |                 ^^^^^^^^^^^^^^ move occurs because `keymap.command` has type `String`, which does not implement the `Copy` trait

Which can be solved by using clone():

run_command(keymap.command.clone());

Is there another solution? I think using clone() like this isn't good practice?

Function run_command takes an ownership of passed String argument. But it cannot do that, since keymap.command is behind a shared reference. Depending on what you are trying to do you should do one of the following:

1. If you want run_command to change passed command, but not reflect that for the caller you should leave run_command as it is now and indeed call clone() on keymap.command. You could pass &String (or &str) to run_command and clone it inside, but it is better to leave that decision to the caller.

2. If you want run_command to change actual keymap.command pass it a &mut String instead. This will also force you to change handle_keymap to take &mut Keymap instead of &Keymap.

3. If you don't want to mutate command inside run_command then don't do it and change it to take string by reference &String (or event better take advantage of deref coercion and pass command as &str).

If you want something different, you will have to be more specific in your question for us to help you.