src/test/ui/extern-flag/noprelude-and-prelude.rs

// check-pass
// aux-crate:noprelude:somedep=somedep.rs
// compile-flags: -Zunstable-options --extern somedep
// edition:2018

// Having a flag with `noprelude` and one without, will add to the prelude.

fn main() {
    somedep::somefun();
}