3 files changed, 27 insertions, 13 deletions
diff --git a/library/alloctests/benches/lib.rs b/library/alloctests/benches/lib.rs
index 2633154318c..721d685527f 100644
--- a/library/alloctests/benches/lib.rs
+++ b/library/alloctests/benches/lib.rs
@@ -1,6 +1,5 @@
 // Disabling in Miri as these would take too long.
 #![cfg(not(miri))]
-#![feature(btree_extract_if)]
 #![feature(iter_next_chunk)]
 #![feature(repr_simd)]
 #![feature(slice_partition_dedup)]
diff --git a/library/alloctests/tests/lib.rs b/library/alloctests/tests/lib.rs
index bf446ae1ba4..49fb21ef5f3 100644
--- a/library/alloctests/tests/lib.rs
+++ b/library/alloctests/tests/lib.rs
@@ -2,7 +2,6 @@
 #![feature(alloc_layout_extra)]
 #![feature(iter_array_chunks)]
 #![feature(assert_matches)]
-#![feature(btree_extract_if)]
 #![feature(wtf8_internals)]
 #![feature(char_max_len)]
 #![feature(cow_is_borrowed)]
@@ -42,12 +41,12 @@
 #![feature(unique_rc_arc)]
 #![feature(macro_metavar_expr_concat)]
 #![feature(vec_peek_mut)]
+#![feature(vec_try_remove)]
 #![allow(internal_features)]
 #![deny(fuzzy_provenance_casts)]
 #![deny(unsafe_op_in_unsafe_fn)]
 
 extern crate alloc;
-extern crate test;
 
 use std::hash::{DefaultHasher, Hash, Hasher};
 
diff --git a/library/alloctests/tests/vec.rs b/library/alloctests/tests/vec.rs
index 00f640cd17e..ea334ab0f14 100644
--- a/library/alloctests/tests/vec.rs
+++ b/library/alloctests/tests/vec.rs
@@ -15,7 +15,7 @@ use std::ops::Bound::*;
 use std::panic::{AssertUnwindSafe, catch_unwind};
 use std::rc::Rc;
 use std::sync::atomic::{AtomicU32, Ordering};
-use std::vec::{Drain, IntoIter};
+use std::vec::{Drain, IntoIter, PeekMut};
 
 use crate::testing::macros::struct_with_counted_drop;
 
@@ -631,6 +631,21 @@ fn test_swap_remove_empty() {
 }
 
 #[test]
+fn test_try_remove() {
+    let mut vec = vec![1, 2, 3];
+    // We are attempting to remove vec[0] which contains 1
+    assert_eq!(vec.try_remove(0), Some(1));
+    // Now `vec` looks like: [2, 3]
+    // We will now try to remove vec[2] which does not exist
+    // This should return `None`
+    assert_eq!(vec.try_remove(2), None);
+
+    // We will try the same thing with an empty vector
+    let mut v: Vec<u8> = vec![];
+    assert!(v.try_remove(0).is_none());
+}
+
+#[test]
 fn test_move_items() {
     let vec = vec![1, 2, 3];
     let mut vec2 = vec![];
@@ -2643,15 +2658,16 @@ fn test_peek_mut() {
     assert!(vec.peek_mut().is_none());
     vec.push(1);
     vec.push(2);
-    if let Some(mut p) = vec.peek_mut() {
-        assert_eq!(*p, 2);
-        *p = 0;
-        assert_eq!(*p, 0);
-        p.pop();
-        assert_eq!(vec.len(), 1);
-    } else {
-        unreachable!()
-    }
+    let mut p = vec.peek_mut().unwrap();
+    assert_eq!(*p, 2);
+    *p = 0;
+    assert_eq!(*p, 0);
+    drop(p);
+    assert_eq!(vec, vec![1, 0]);
+    let p = vec.peek_mut().unwrap();
+    let p = PeekMut::pop(p);
+    assert_eq!(p, 0);
+    assert_eq!(vec, vec![1]);
 }
 
 /// This assortment of tests, in combination with miri, verifies we handle UB on fishy arguments