Auto merge of #58644 - Centril:rollup, r=Centril

Rollup of 17 pull requests

Successful merges:

 - #57656 (Deprecate the unstable Vec::resize_default)
 - #58059 (deprecate before_exec in favor of unsafe pre_exec)
 - #58064 (override `VecDeque::try_rfold`, also update iterator)
 - #58198 (Suggest removing parentheses surrounding lifetimes)
 - #58431 (fix overlapping references in BTree)
 - #58555 (Add a note about 2018e if someone uses `try {` in 2015e)
 - #58588 (remove a bit of dead code)
 - #58589 (cleanup macro after 2018 transition)
 - #58591 (Dedup a rustdoc diagnostic construction)
 - #58600 (fix small documentation typo)
 - #58601 (Search for target_triple.json only if builtin target not found)
 - #58606 (Docs: put Future trait into spotlight)
 - #58607 (Fixes #58586: Make E0505 erronous example fail for the 2018 edition)
 - #58615 (miri: explain why we use static alignment in ref-to-place conversion)
 - #58620 (introduce benchmarks of BTreeSet.intersection)
 - #58621 (Update miri links)
 - #58632 (Make std feature list sorted)

Failed merges:

r? @ghost

1 files changed, 64 insertions, 0 deletions

diff --git a/src/liballoc/tests/vec_deque.rs b/src/liballoc/tests/vec_deque.rs
index e0cb0e7a9e7..16ddc1444fc 100644
--- a/src/liballoc/tests/vec_deque.rs
+++ b/src/liballoc/tests/vec_deque.rs
@@ -1465,6 +1465,15 @@ fn test_try_fold_unit() {
     assert_eq!(Some(()), v.into_iter().try_fold((), |(), ()| Some(())));
 }
 
+
+#[test]
+fn test_try_fold_unit_none() {
+    let v: std::collections::VecDeque<()> = [(); 10].iter().cloned().collect();
+    let mut iter = v.into_iter();
+    assert!(iter.try_fold((), |_, _| None).is_none());
+    assert_eq!(iter.len(), 9);
+}
+
 #[test]
 fn test_try_fold_rotated() {
     let mut v: VecDeque<_> = (0..12).collect();
@@ -1477,3 +1486,58 @@ fn test_try_fold_rotated() {
         assert_eq!(Ok::<_, ()>(66), v.iter().try_fold(0, |a, b| Ok(a + b)));
     }
 }
+
+#[test]
+fn test_try_fold_moves_iter() {
+    let v: VecDeque<_> = [10, 20, 30, 40, 100, 60, 70, 80, 90].iter().collect();
+    let mut iter = v.into_iter();
+    assert_eq!(iter.try_fold(0_i8, |acc, &x| acc.checked_add(x)), None);
+    assert_eq!(iter.next(), Some(&60));
+}
+
+#[test]
+fn test_try_fold_exhaust_wrap() {
+    let mut v = VecDeque::with_capacity(7);
+    v.push_back(1);
+    v.push_back(1);
+    v.push_back(1);
+    v.pop_front();
+    v.pop_front();
+    let mut iter = v.iter();
+    let _ = iter.try_fold(0, |_, _| Some(1));
+    assert!(iter.is_empty());
+}
+
+#[test]
+fn test_try_fold_wraparound() {
+    let mut v = VecDeque::with_capacity(8);
+    v.push_back(7);
+    v.push_back(8);
+    v.push_back(9);
+    v.push_front(2);
+    v.push_front(1);
+    let mut iter = v.iter();
+    let _ = iter.find(|&&x| x == 2);
+    assert_eq!(Some(&7), iter.next());
+}
+
+#[test]
+fn test_try_rfold_rotated() {
+    let mut v: VecDeque<_> = (0..12).collect();
+    for n in 0..10 {
+        if n & 1 == 0 {
+            v.rotate_left(n);
+        } else {
+            v.rotate_right(n);
+        }
+        assert_eq!(Ok::<_, ()>(66), v.iter().try_rfold(0, |a, b| Ok(a + b)));
+    }
+}
+
+#[test]
+fn test_try_rfold_moves_iter() {
+    let v : VecDeque<_> = [10, 20, 30, 40, 100, 60, 70, 80, 90].iter().collect();
+    let mut iter = v.into_iter();
+    assert_eq!(iter.try_rfold(0_i8, |acc, &x| acc.checked_add(x)), None);
+    assert_eq!(iter.next_back(), Some(&70));
+}