&mut Struct to Struct (Rust)

muttononmut.rs

impl From<(PartialUser, UserEntry, &str)> for AuthorizedUser {
    fn from((user, entry, jwt_token): (PartialUser, UserEntry, &str)) -> Self {
        let join_names_fn =
            |first_name: Option<String>, middle_name: Option<String>, last_name: Option<String>| {
                let names = [first_name, middle_name, last_name];
                names
                    .iter()
                    .filter_map(|name| name.as_ref())
                    .map(|name| name.to_string())
                    .collect::<Vec<String>>()
                    .join(" ")
            };
        let permissions = user.permissions_cache.and_then(|permissions| {
            serde_json::from_slice::<Permissions>(&permissions)
                .ok()
                .and_then(|permissions| serde_json::to_string(&permissions).ok())
        });
        let mut binding = AuthorizedUser {
            uuid: user.uuid,
            jwt_token: jwt_token.to_owned(),
            permissions,
            ..Default::default()
        };
        let auth_user = binding.as_mut();
        match entry {
            UserEntry::Person(person) => {
                auth_user.email = user.email.or(person.email);
                auth_user.full_name = join_names_fn(
                    string_to_option(person.first_name),
                    person.middle_name,
                    person.second_name,
                );
            },
            UserEntry::Client(client) => {
                auth_user.email = user.email.or(client.email);
                auth_user.full_name = join_names_fn(
                    string_to_option(client.first_name),
                    client.middle_name,
                    client.second_name,
                );
            },
            UserEntry::Contractor(contractor) => {
                auth_user.email = user.email.or(contractor.email);
                auth_user.full_name = join_names_fn(
                    string_to_option(contractor.first_name),
                    contractor.middle_name,
                    contractor.second_name,
                );
            },
        }
        core::mem::take(auth_user)
    }
}