rust/tests/ui/rfc-1445-restrict-constants-in-patterns/cant-hide-behind-direct-struct-param.rs
2023-01-11 09:32:08 +00:00

27 lines
868 B
Rust

// This is part of a set of tests exploring the different ways a
// structural-match ADT might try to hold a
// non-structural-match in hidden manner that lets matches
// through that we had intended to reject.
//
// See discussion on rust-lang/rust#62307 and rust-lang/rust#62339
#![warn(indirect_structural_match)]
struct NoDerive(i32);
// This impl makes NoDerive irreflexive.
impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
impl Eq for NoDerive { }
#[derive(PartialEq, Eq)]
struct WrapParam<T>(T);
const WRAP_DIRECT_PARAM: WrapParam<NoDerive> = WrapParam(NoDerive(0));
fn main() {
match WRAP_DIRECT_PARAM {
WRAP_DIRECT_PARAM => { panic!("WRAP_DIRECT_PARAM matched itself"); }
//~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]`
_ => { println!("WRAP_DIRECT_PARAM did not match itself"); }
}
}