Add VecDeque::extend from vec::IntoIter and slice::Iter specializations

2 files changed, 6 insertions, 1 deletions

diff --git a/library/alloc/src/vec/into_iter.rs b/library/alloc/src/vec/into_iter.rs
index 03c532bb697..8134eea570a 100644
--- a/library/alloc/src/vec/into_iter.rs
+++ b/library/alloc/src/vec/into_iter.rs
@@ -121,6 +121,11 @@ impl<T, A: Allocator> IntoIter<T, A> {
             ptr::drop_in_place(remaining);
         }
     }
+
+    /// Forgets to Drop the remaining elements while still allowing the backing allocation to be freed.
+    pub(crate) fn forget_remaining_elements(&mut self) {
+        self.ptr = self.end;
+    }
 }
 
 #[stable(feature = "vec_intoiter_as_ref", since = "1.46.0")]
diff --git a/library/alloc/src/vec/spec_extend.rs b/library/alloc/src/vec/spec_extend.rs
index c3b4534096d..506ee0ecfa2 100644
--- a/library/alloc/src/vec/spec_extend.rs
+++ b/library/alloc/src/vec/spec_extend.rs
@@ -62,7 +62,7 @@ impl<T, A: Allocator> SpecExtend<T, IntoIter<T>> for Vec<T, A> {
         unsafe {
             self.append_elements(iterator.as_slice() as _);
         }
-        iterator.ptr = iterator.end;
+        iterator.forget_remaining_elements();
     }
 }