Fix initWithPtr: method in class_with_lifetime example

Author: madsmtm

objc2-foundation/examples/class_with_lifetime.rs

@@ -1,3 +1,4 @@
+#![deny(unsafe_op_in_unsafe_fn)]
 use std::marker::PhantomData;
 use std::sync::Once;
 
@@ -50,15 +51,22 @@ impl<'a> MyObject<'a> {
             let mut decl = ClassDecl::new("MyObject", superclass).unwrap();
             decl.add_ivar::<Option<&mut u8>>("_number_ptr");
 
-            extern "C" fn init_with_ptr(this: &mut Object, _cmd: Sel, ptr: *mut u8) -> *mut Object {
-                unsafe {
-                    this.set_ivar("_number_ptr", ptr);
+            unsafe extern "C" fn init_with_ptr(
+                this: *mut Object,
+                _cmd: Sel,
+                ptr: *mut u8,
+            ) -> *mut Object {
+                let this: *mut Object = unsafe { msg_send![super(this, NSObject::class()), init] };
+                if let Some(this) = unsafe { this.as_mut() } {
+                    unsafe {
+                        this.set_ivar("_number_ptr", ptr);
+                    }
                 }
                 this
             }
 
             unsafe {
-                let init_with_ptr: extern "C" fn(&mut Object, Sel, *mut u8) -> *mut Object =
+                let init_with_ptr: unsafe extern "C" fn(*mut Object, Sel, *mut u8) -> *mut Object =
                     init_with_ptr;
                 decl.add_method(sel!(initWithPtr:), init_with_ptr);
             }