#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use std::fmt;
struct Foo;
impl fmt::Display for Foo {
    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
        let c = formatter.fill();
        if let Some(width) = formatter.width() {
            for _ in 0..width {
                write!(formatter, "{c}")?;
            }
            Ok(())
        } else {
            write!(formatter, "{c}")
        }
    }
}
fn main() {
    assert_eq!(format!("{Foo:G>3}"), "GGG");
    assert_eq!(format!("{Foo:t>6}"), "tttttt");
}