tests/ui/methods/supertrait-shadowing/trivially-false-subtrait.rs

//@ run-pass

// Make sure we don't prefer a subtrait that we would've otherwise eliminated
// in `consider_probe` during method probing.

#![allow(dead_code)]

struct W<T>(T);

trait Upstream {
    fn hello(&self) -> &'static str {
        "upstream"
    }
}
impl<T> Upstream for T {}

trait Downstream: Upstream {
    fn hello(&self) -> &'static str {
        "downstream"
    }
}
impl<T> Downstream for W<T> where T: Foo {}

trait Foo {}

fn main() {
    let x = W(1i32);
    assert_eq!(x.hello(), "upstream");
}