Attempt to fix segfault in window drop (#10690)

Conrad Irwin created 2 years ago

By default NSWindow's release themselves when closed, which doesn't
interact well with rust's lifetime system.

Disable that behaviour, and explicitly release the NSWindow when the
window handle is dropped.

Release Notes:

- Fixed a (rare) panic when closing a window.

Change summary

crates/gpui/src/platform/mac/window.rs | 29 +++++++++++++--------------
1 file changed, 14 insertions(+), 15 deletions(-)

Detailed changes

crates/gpui/src/platform/mac/window.rs

@@ -337,7 +337,6 @@ struct MacWindowState {
     handle: AnyWindowHandle,
     executor: ForegroundExecutor,
     native_window: id,
-    native_window_was_closed: bool,
     native_view: NonNull<Object>,
     display_link: Option<DisplayLink>,
     renderer: renderer::Renderer,
@@ -605,6 +604,10 @@ impl MacWindow {
                 registerForDraggedTypes:
                     NSArray::arrayWithObject(nil, NSFilenamesPboardType)
             ];
+            let () = msg_send![
+                native_window,
+                setReleasedWhenClosed: NO
+            ];
 
             let native_view: id = msg_send![VIEW_CLASS, alloc];
             let native_view = NSView::init(native_view);
@@ -622,7 +625,6 @@ impl MacWindow {
                 handle,
                 executor,
                 native_window,
-                native_window_was_closed: false,
                 native_view: NonNull::new_unchecked(native_view),
                 display_link: None,
                 renderer: renderer::new_renderer(
@@ -770,19 +772,17 @@ impl Drop for MacWindow {
         this.renderer.destroy();
         let window = this.native_window;
         this.display_link.take();
-        if !this.native_window_was_closed {
-            unsafe {
-                this.native_window.setDelegate_(nil);
-            }
-
-            this.executor
-                .spawn(async move {
-                    unsafe {
-                        window.close();
-                    }
-                })
-                .detach();
+        unsafe {
+            this.native_window.setDelegate_(nil);
         }
+        this.executor
+            .spawn(async move {
+                unsafe {
+                    window.close();
+                    window.autorelease();
+                }
+            })
+            .detach();
     }
 }
 
@@ -1592,7 +1592,6 @@ extern "C" fn close_window(this: &Object, _: Sel) {
         let close_callback = {
             let window_state = get_window_state(this);
             let mut lock = window_state.as_ref().lock();
-            lock.native_window_was_closed = true;
             lock.close_callback.take()
         };