rust/tests/ui/generator/yielding-in-match-guards.rs
2023-01-11 09:32:08 +00:00

54 lines
1.0 KiB
Rust

// build-pass
// edition:2018
// This test is derived from
// https://github.com/rust-lang/rust/issues/72651#issuecomment-668720468
// This test demonstrates that, in `async fn g()`,
// indeed a temporary borrow `y` from `x` is live
// while `f().await` is being evaluated.
// Thus, `&'_ u8` should be included in type signature
// of the underlying generator.
#![feature(if_let_guard)]
async fn f() -> u8 { 1 }
async fn foo() -> [bool; 10] { [false; 10] }
pub async fn g(x: u8) {
match x {
y if f().await == y => (),
_ => (),
}
}
// #78366: check the reference to the binding is recorded even if the binding is not autorefed
async fn h(x: usize) {
match x {
y if foo().await[y] => (),
_ => (),
}
}
async fn i(x: u8) {
match x {
y if f().await == y + 1 => (),
_ => (),
}
}
async fn j(x: u8) {
match x {
y if let (1, 42) = (f().await, y) => (),
_ => (),
}
}
fn main() {
let _ = g(10);
let _ = h(9);
let _ = i(8);
let _ = j(7);
}