Remove ProtocolObject::from_mut and AutoreleasePool::ptr_as_mut

Part of #563

crates/objc2/CHANGELOG.md

@@ -46,6 +46,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
   - `Retained::as_mut_ptr`.
   - `Retained::autorelease_mut`.
   - `DeclaredClass::ivars_mut`.
+  - `ProtocolObject::from_mut`.
+  - `AutoreleasePool::ptr_as_mut`.
 * **BREAKING**: Disallow `&mut` message receivers (except in the special case
   when the object is `AnyObject`, for better backwards compatibility with
   `objc`).

crates/objc2/src/rc/autorelease.rs

@@ -141,10 +141,6 @@ pub struct AutoreleasePool<'pool> {
     ///     pub fn autorelease(self, s: String) -> &'pool str {
     ///         &*self.0.0.alloc(s)
     ///     }
-    ///
-    ///     pub fn autorelease_mut(self, s: String) -> &'pool mut str {
-    ///         &mut *self.0.0.alloc(s)
-    ///     }
     /// }
     ///
     /// pub fn autoreleasepool<F, R>(f: F) -> R
@@ -204,8 +200,6 @@ impl<'pool> AutoreleasePool<'pool> {
     /// objects, since it binds the lifetime of the reference to the pool, and
     /// does some extra checks when debug assertions are enabled.
     ///
-    /// For the mutable counterpart see [`ptr_as_mut`](#method.ptr_as_mut).
-    ///
     ///
     /// # Safety
     ///
@@ -217,26 +211,6 @@ impl<'pool> AutoreleasePool<'pool> {
         // SAFETY: Checked by the caller
         unsafe { ptr.as_ref().unwrap_unchecked() }
     }
-
-    /// Returns a unique reference to the given autoreleased pointer object.
-    ///
-    /// This is the preferred way to make mutable references from autoreleased
-    /// objects, since it binds the lifetime of the reference to the pool, and
-    /// does some extra checks when debug assertions are enabled.
-    ///
-    /// For the shared counterpart see [`ptr_as_ref`](#method.ptr_as_ref).
-    ///
-    ///
-    /// # Safety
-    ///
-    /// This is equivalent to `&mut *ptr`, and shares the unsafety of that,
-    /// except the lifetime is bound to the pool instead of being unbounded.
-    #[inline]
-    pub unsafe fn ptr_as_mut<T: ?Sized>(self, ptr: *mut T) -> &'pool mut T {
-        self.__verify_is_inner();
-        // SAFETY: Checked by the caller
-        unsafe { ptr.as_mut().unwrap_unchecked() }
-    }
 }
 
 /// We use a macro here so that the documentation is included whether the

crates/objc2/src/runtime/protocol_object.rs

@@ -96,23 +96,6 @@ impl<P: ?Sized> ProtocolObject<P> {
         unsafe { ptr.as_ref() }
     }
 
-    /// Get a mutable type-erased reference from a type implementing a
-    /// protocol.
-    #[inline]
-    pub fn from_mut<T: ?Sized + Message>(obj: &mut T) -> &mut Self
-    where
-        P: ImplementedBy<T>,
-    {
-        let ptr: NonNull<T> = NonNull::from(obj);
-        let mut ptr: NonNull<Self> = ptr.cast();
-        // SAFETY: Same as `as_protocol`.
-        //
-        // Since the reference came from a mutable reference to start with,
-        // returning a mutable reference here is safe (the lifetime of the
-        // returned reference is bound to the input).
-        unsafe { ptr.as_mut() }
-    }
-
     /// Get a type-erased object from a type implementing a protocol.
     ///
     /// Soft-deprecated alias of [`ProtocolObject::from_retained`].