From 4cc46df98cd77abf141ac5c656bbc6234e260bd8 Mon Sep 17 00:00:00 2001
From: Maybe Waffle <waffle.lapkin@tasking.com>
Date: Wed, 8 Nov 2023 01:24:58 +0000
Subject: [PATCH] Add `replace` and `swap` convenience methods to `NonNull`

---
 library/core/src/ptr/non_null.rs | 35 ++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/library/core/src/ptr/non_null.rs b/library/core/src/ptr/non_null.rs
index 1efff12ebc9..6e92ea86dd0 100644
--- a/library/core/src/ptr/non_null.rs
+++ b/library/core/src/ptr/non_null.rs
@@ -1187,6 +1187,41 @@ pub unsafe fn write_volatile(self, val: T)
         // SAFETY: the caller must uphold the safety contract for `write_unaligned`.
         unsafe { ptr::write_unaligned(self.as_ptr(), val) }
     }
+
+    /// Replaces the value at `self` with `src`, returning the old
+    /// value, without dropping either.
+    ///
+    /// See [`ptr::replace`] for safety concerns and examples.
+    ///
+    /// [`ptr::replace`]: crate::ptr::replace()
+    #[unstable(feature = "non_null_convenience", issue = "117691")]
+    #[inline(always)]
+    pub unsafe fn replace(self, src: T) -> T
+    where
+        T: Sized,
+    {
+        // SAFETY: the caller must uphold the safety contract for `replace`.
+        unsafe { ptr::replace(self.as_ptr(), src) }
+    }
+
+    /// Swaps the values at two mutable locations of the same type, without
+    /// deinitializing either. They may overlap, unlike `mem::swap` which is
+    /// otherwise equivalent.
+    ///
+    /// See [`ptr::swap`] for safety concerns and examples.
+    ///
+    /// [`ptr::swap`]: crate::ptr::swap()
+    #[unstable(feature = "non_null_convenience", issue = "117691")]
+    #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")]
+    //#[rustc_const_unstable(feature = "const_swap", issue = "83163")]
+    #[inline(always)]
+    pub const unsafe fn swap(self, with: NonNull<T>)
+    where
+        T: Sized,
+    {
+        // SAFETY: the caller must uphold the safety contract for `swap`.
+        unsafe { ptr::swap(self.as_ptr(), with.as_ptr()) }
+    }
 }
 
 impl<T> NonNull<[T]> {