Unable to use GET macro and prefix route with '@'

[brianjd]

Rocket Version

0.5.1

Operating System

Linux

Rust Toolchain Version

rustc 1.88

What happened?

When trying to define a route path like this using the macro, prefixed with @, the attribute passed has this error:

#[get("/@<username>")]
fn user(username: &str) -> String {

the trait bound `&str: FromRequest<'_>` is not satisfied
the following other types implement trait `FromRequest<'r>`:
  &'r ContentType
  &'r Limits
  &'r Route
  &'r rocket::Config
  &'r rocket::State<T>
  &'r rocket::http::Accept
  &'r rocket::http::CookieJar<'r>
  &'r rocket::http::uri::Host<'r>

As per HTTP spec you should be able to use @, emojis, etc in URL.

Test Case

===

Log Output

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Additional Context

No response

System Checks

• My bug report relates to functionality.
• I have tested against the latest Rocket release or a recent git commit.
• I have tested against the latest stable rustc toolchain.
• I was unable to find this issue previously reported.

[martynp]

Do you need to be able to support multiple prefixes within the macro functions?

The following would enforce the formatting:

#[get("/user/<username>")]
fn other(username: &str) -> Option<String> {

    if !username.starts_with("@") {
        return None;
    }

    Some(format!("Hello {username}"))
}