macOS: skip releasing unavailable monitors

Prevent assertion error when trying to close a fullscreen window that
was on a display that got disconnected.

src/changelog/unreleased.md

@@ -110,3 +110,4 @@ changelog entry.
 ### Fixed
 
 - On Web, pen events are now routed through to `WindowEvent::Cursor*`.
+- On macOS, fix panic when releasing not available monitor.

src/platform_impl/apple/appkit/window_delegate.rs

@@ -1428,13 +1428,7 @@ impl WindowDelegate {
  toggle_fullscreen(self.window());
  },
  (Some(Fullscreen::Exclusive(ref video_mode)), None) => {
- unsafe {
- ffi::CGRestorePermanentDisplayConfiguration();
- assert_eq!(
- ffi::CGDisplayRelease(video_mode.monitor().native_identifier()),
- ffi::kCGErrorSuccess
- );
- };
+ restore_and_release_display(&video_mode.monitor());
  toggle_fullscreen(self.window());
  },
  (Some(Fullscreen::Borderless(_)), Some(Fullscreen::Exclusive(_))) => {
@@ -1465,13 +1459,7 @@ impl WindowDelegate {
  );
  app.setPresentationOptions(presentation_options);
 
- unsafe {
- ffi::CGRestorePermanentDisplayConfiguration();
- assert_eq!(
- ffi::CGDisplayRelease(video_mode.monitor().native_identifier()),
- ffi::kCGErrorSuccess
- );
- };
+ restore_and_release_display(&video_mode.monitor());
 
  // Restore the normal window level following the Borderless fullscreen
  // `CGShieldingWindowLevel() + 1` hack.
@@ -1667,6 +1655,21 @@ impl WindowDelegate {
  }
 }
 
+fn restore_and_release_display(monitor: &MonitorHandle) {
+ let available_monitors = monitor::available_monitors();
+ if available_monitors.contains(monitor) {
+ unsafe {
+ ffi::CGRestorePermanentDisplayConfiguration();
+ assert_eq!(ffi::CGDisplayRelease(monitor.native_identifier()), ffi::kCGErrorSuccess);
+ };
+ } else {
+ warn!(
+ monitor = monitor.name(),
+ "Tried to restore exclusive fullscreen on a monitor that is no longer available"
+ );
+ }
+}
+
 impl WindowExtMacOS for WindowDelegate {
  #[inline]
  fn simple_fullscreen(&self) -> bool {