Test that .collect_into_vec() drops written elements on unwinding
@@ -342,3 +342,58 @@ fn zip() {
check(&v[..5], || (0..5).into_par_iter().zip(10..20));
check(&v[..5], || (0..10).into_par_iter().zip(10..15));
}
+
+#[test]
+fn collect_drop_on_unwind() {
+ use std::panic;
+ use std::sync::Mutex;
+
+ struct Recorddrop<'a>(i64, &'a Mutex<Vec<i64>>);
+
+ impl<'a> Drop for Recorddrop<'a> {
+ fn drop(&mut self) {
+ self.1.lock().unwrap().push(self.0);
+ }
+ }
+
+ let test_collect_panic = |will_panic: bool| {
+ let test_vec_len = 1024;
+ let panic_point = 740;
+
+ let mut inserts = Mutex::new(Vec::new());
+ let mut drops = Mutex::new(Vec::new());
+
+ let mut a = (0..test_vec_len).collect::<Vec<_>>();
+ let b = (0..test_vec_len).collect::<Vec<_>>();
+
+ let _result = panic::catch_unwind(panic::AssertUnwindSafe(|| {
+ let mut result = Vec::new();
+ a.par_iter_mut()
+ .zip(&b)
+ .map(|(&mut a, &b)| {
+ if a > panic_point && will_panic {
+ panic!("unwinding for test");
+ }
+ let elt = a + b;
+ inserts.lock().unwrap().push(elt);
+ Recorddrop(elt, &drops)
+ })
+ .collect_into_vec(&mut result);
+ }));
+
+ let inserts = inserts.get_mut().unwrap();
+ let drops = drops.get_mut().unwrap();
+ println!("{:?}", inserts);
+ println!("{:?}", drops);
+
+ assert_eq!(inserts.len(), drops.len(), "Incorrect number of drops");
+ // sort to normalize order
+ inserts.sort();
+ drops.sort();
+ assert_eq!(inserts, drops, "Incorrect elements were dropped");
+ };
+
+ for &should_panic in &[true, false] {
+ test_collect_panic(should_panic);
+ }
+}
