rust/tests/ui/for-loop-while/cleanup-rvalue-during-if-and-while.rs

45 lines
885 B
Rust

//@ run-pass
// This test verifies that temporaries created for `while`'s and `if`
// conditions are dropped after the condition is evaluated.
// FIXME(static_mut_refs): this could use an atomic
#![allow(static_mut_refs)]
struct Temporary;
static mut DROPPED: isize = 0;
impl Drop for Temporary {
fn drop(&mut self) {
unsafe { DROPPED += 1; }
}
}
impl Temporary {
fn do_stuff(&self) -> bool {true}
}
fn borrow() -> Box<Temporary> { Box::new(Temporary) }
pub fn main() {
let mut i = 0;
// This loop's condition
// should call `Temporary`'s
// `drop` 6 times.
while borrow().do_stuff() {
i += 1;
unsafe { assert_eq!(DROPPED, i) }
if i > 5 {
break;
}
}
// This if condition should
// call it 1 time
if borrow().do_stuff() {
unsafe { assert_eq!(DROPPED, i + 1) }
}
}