rust/tests/ui/panics/panic-set-handler.rs

//@ run-fail
//@ error-pattern:greetings from the panic handler
//@ needs-subprocess

use std::panic;

fn main() {
    panic::set_hook(Box::new(|i| {
        eprintln!("greetings from the panic handler");
    }));
    panic!("foobar");
}