use std::collections::HashMap;pub fn format_env_display<S: AsRef<str>>(    env: Option<&HashMap<String, String>>,    env_vars: &[S],) -> String {    let mut parts: Vec<String> = Vec::new();    if let Some(map) = env {        let mut pairs: Vec<_> = map.iter().collect();        pairs.sort_by_key(|(key, _)| *key);        parts.extend(pairs.into_iter().map(|(key, _)| format!("{key}=*****")));    }    if !env_vars.is_empty() {        parts.extend(env_vars.iter().map(|var| format!("{}=*****", var.as_ref())));    }    if parts.is_empty() {        "-".to_string()    } else {        parts.join(", ")    }}#[cfg(test)]mod tests {    use super::*;    #[test]    fn returns_dash_when_empty() {        let empty_vars: &[String] = &[];        assert_eq!(format_env_display(/*env*/ None, empty_vars), "-");        let empty_map = HashMap::new();        assert_eq!(format_env_display(Some(&empty_map), empty_vars), "-");    }    #[test]    fn formats_sorted_env_pairs() {        let mut env = HashMap::new();        env.insert("B".to_string(), "two".to_string());        env.insert("A".to_string(), "one".to_string());        assert_eq!(            format_env_display(Some(&env), &[] as &[String]),            "A=*****, B=*****"        );    }    #[test]    fn formats_env_vars_with_dollar_prefix() {        let vars = vec!["TOKEN".to_string(), "PATH".to_string()];        assert_eq!(            format_env_display(/*env*/ None, &vars),            "TOKEN=*****, PATH=*****"        );    }    #[test]    fn combines_env_pairs_and_vars() {        let mut env = HashMap::new();        env.insert("HOME".to_string(), "/tmp".to_string());        let vars = vec!["TOKEN".to_string()];        assert_eq!(            format_env_display(Some(&env), &vars),            "HOME=*****, TOKEN=*****"        );    }}