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// run-pass
// needs-unwind
// See `mir_drop_order.rs` for more information
#![feature(let_chains)]
#![allow(irrefutable_let_patterns)]
use std::cell::RefCell;
use std::panic;
pub struct DropLogger<'a, T> {
extra: T,
id: usize,
log: &'a panic::AssertUnwindSafe<RefCell<Vec<usize>>>,
}
impl<'a, T> Drop for DropLogger<'a, T> {
fn drop(&mut self) {
self.log.0.borrow_mut().push(self.id);
}
}
struct InjectedFailure;
#[allow(unreachable_code)]
fn main() {
let log = panic::AssertUnwindSafe(RefCell::new(vec![]));
let d = |id, extra| DropLogger { extra, id: id, log: &log };
let get = || -> Vec<_> {
let mut m = log.0.borrow_mut();
let n = m.drain(..);
n.collect()
};
{
let _x = (
d(
0,
d(
1,
if let Some(_) = d(2, Some(true)).extra && let DropLogger { .. } = d(3, None) {
None
} else {
Some(true)
}
).extra
),
d(4, None),
&d(5, None),
d(6, None),
if let DropLogger { .. } = d(7, None) && let DropLogger { .. } = d(8, None) {
d(9, None)
}
else {
// 10 is not constructed
d(10, None)
},
);
assert_eq!(get(), vec![8, 7, 1, 3, 2]);
}
assert_eq!(get(), vec![0, 4, 6, 9, 5]);
let _ = std::panic::catch_unwind(|| {
(
d(
11,
d(
12,
if let Some(_) = d(13, Some(true)).extra
&& let DropLogger { .. } = d(14, None)
{
None
} else {
Some(true)
}
).extra
),
d(15, None),
&d(16, None),
d(17, None),
if let DropLogger { .. } = d(18, None) && let DropLogger { .. } = d(19, None) {
d(20, None)
}
else {
// 10 is not constructed
d(21, None)
},
panic::panic_any(InjectedFailure)
);
});
assert_eq!(get(), vec![20, 17, 15, 11, 19, 18, 16, 12, 14, 13]);
}
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