From a0634fa79ea2289e3fb1c187e3cc44c0c25b60a6 Mon Sep 17 00:00:00 2001
From: Antonio Scandurra <me@as-cii.com>
Date: Wed, 18 Oct 2023 18:39:29 +0200
Subject: [PATCH] Checkpoint

---
 crates/gpui3/src/app.rs    |  7 ++++---
 crates/gpui3/src/window.rs | 43 ++++++++++++++++++++++++--------------
 2 files changed, 31 insertions(+), 19 deletions(-)

diff --git a/crates/gpui3/src/app.rs b/crates/gpui3/src/app.rs
index ed094a24ca..663995e893 100644
--- a/crates/gpui3/src/app.rs
+++ b/crates/gpui3/src/app.rs
@@ -238,7 +238,6 @@ impl AppContext {
                 });
 
                 if blur_window {
-                    cx.window.focus = None;
                     cx.blur();
                 }
             })
@@ -263,12 +262,14 @@ impl AppContext {
         self.update_window(window_id, |cx| {
             if cx.window.focus == focused {
                 let mut listeners = mem::take(&mut cx.window.focus_listeners);
-                let focused = focused.map(|id| FocusHandle::for_id(id, &cx.window.focus_handles));
+                let focused =
+                    focused.map(|id| FocusHandle::for_id(id, &cx.window.focus_handles).unwrap());
                 let blurred = cx
                     .window
                     .last_blur
+                    .take()
                     .unwrap()
-                    .map(|id| FocusHandle::for_id(id, &cx.window.focus_handles));
+                    .and_then(|id| FocusHandle::for_id(id, &cx.window.focus_handles));
                 let event = FocusEvent { focused, blurred };
                 for listener in &listeners {
                     listener(&event, cx);
diff --git a/crates/gpui3/src/window.rs b/crates/gpui3/src/window.rs
index ed1ca74846..c1507df14e 100644
--- a/crates/gpui3/src/window.rs
+++ b/crates/gpui3/src/window.rs
@@ -12,7 +12,7 @@ use crate::{
 use anyhow::Result;
 use collections::HashMap;
 use derive_more::{Deref, DerefMut};
-use parking_lot::{RwLock, RwLockUpgradableReadGuard};
+use parking_lot::RwLock;
 use slotmap::SlotMap;
 use smallvec::SmallVec;
 use std::{
@@ -24,7 +24,7 @@ use std::{
     mem,
     sync::{
         atomic::{AtomicUsize, Ordering::SeqCst},
-        Arc, Weak,
+        Arc,
     },
 };
 use util::ResultExt;
@@ -57,10 +57,9 @@ type AnyKeyUpListener =
 
 slotmap::new_key_type! { pub struct FocusId; }
 
-#[derive(Clone)]
 pub struct FocusHandle {
     pub(crate) id: FocusId,
-    handles: Weak<RwLock<SlotMap<FocusId, AtomicUsize>>>,
+    handles: Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
 }
 
 impl FocusHandle {
@@ -68,20 +67,24 @@ impl FocusHandle {
         let id = handles.write().insert(AtomicUsize::new(1));
         Self {
             id,
-            handles: Arc::downgrade(handles),
+            handles: handles.clone(),
         }
     }
 
     pub(crate) fn for_id(
         id: FocusId,
         handles: &Arc<RwLock<SlotMap<FocusId, AtomicUsize>>>,
-    ) -> Self {
-        let lock = handles.upgradable_read();
-        let ref_count = lock.get(id).expect("all focus handles dropped for id");
-        ref_count.fetch_add(1, SeqCst);
-        Self {
-            id,
-            handles: Arc::downgrade(handles),
+    ) -> Option<Self> {
+        let lock = handles.read();
+        let ref_count = lock.get(id)?;
+        if ref_count.load(SeqCst) == 0 {
+            None
+        } else {
+            ref_count.fetch_add(1, SeqCst);
+            Some(Self {
+                id,
+                handles: handles.clone(),
+            })
         }
     }
 
@@ -112,6 +115,12 @@ impl FocusHandle {
     }
 }
 
+impl Clone for FocusHandle {
+    fn clone(&self) -> Self {
+        Self::for_id(self.id, &self.handles).unwrap()
+    }
+}
+
 impl PartialEq for FocusHandle {
     fn eq(&self, other: &Self) -> bool {
         self.id == other.id
@@ -122,9 +131,11 @@ impl Eq for FocusHandle {}
 
 impl Drop for FocusHandle {
     fn drop(&mut self) {
-        if let Some(handles) = self.handles.upgrade() {
-            handles.read().get(self.id).unwrap().fetch_sub(1, SeqCst);
-        }
+        self.handles
+            .read()
+            .get(self.id)
+            .unwrap()
+            .fetch_sub(1, SeqCst);
     }
 }
 
@@ -279,7 +290,7 @@ impl<'a, 'w> WindowContext<'a, 'w> {
     pub fn focused(&self) -> Option<FocusHandle> {
         self.window
             .focus
-            .map(|id| FocusHandle::for_id(id, &self.window.focus_handles))
+            .and_then(|id| FocusHandle::for_id(id, &self.window.focus_handles))
     }
 
     pub fn focus(&mut self, handle: &FocusHandle) {