From e3bb5e5103ca7dcbdda1b327414c4b50cd82291f Mon Sep 17 00:00:00 2001
From: Max Brunsfeld <maxbrunsfeld@gmail.com>
Date: Tue, 8 Aug 2023 17:39:05 -0700
Subject: [PATCH] Fix failure to remove hovered region_ids on element removal

Co-authored-by: Mikayla <mikayla@zed.dev>
---
 crates/gpui/src/app/window.rs         | 13 +++++++++----
 crates/gpui/src/scene/mouse_region.rs |  2 +-
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/crates/gpui/src/app/window.rs b/crates/gpui/src/app/window.rs
index 789341d46fa4788e24c7b4d7b1e44d0558e1f3b7..889dd2510eb06c733b288fd49909b3bec121e094 100644
--- a/crates/gpui/src/app/window.rs
+++ b/crates/gpui/src/app/window.rs
@@ -51,8 +51,8 @@ pub struct Window {
     cursor_regions: Vec<CursorRegion>,
     mouse_regions: Vec<(MouseRegion, usize)>,
     last_mouse_moved_event: Option<Event>,
-    pub(crate) hovered_region_ids: HashSet<MouseRegionId>,
-    pub(crate) clicked_region_ids: HashSet<MouseRegionId>,
+    pub(crate) hovered_region_ids: Vec<MouseRegionId>,
+    pub(crate) clicked_region_ids: Vec<MouseRegionId>,
     pub(crate) clicked_region: Option<(MouseRegionId, MouseButton)>,
     mouse_position: Vector2F,
     text_layout_cache: TextLayoutCache,
@@ -664,6 +664,7 @@ impl<'a> WindowContext<'a> {
                     let mut highest_z_index = None;
                     let mouse_position = self.window.mouse_position.clone();
                     let window = &mut *self.window;
+                    let prev_hovered_regions = mem::take(&mut window.hovered_region_ids);
                     for (region, z_index) in window.mouse_regions.iter().rev() {
                         // Allow mouse regions to appear transparent to hovers
                         if !region.hoverable {
@@ -682,7 +683,11 @@ impl<'a> WindowContext<'a> {
                         // highest_z_index is set.
                         if contains_mouse && z_index == highest_z_index.unwrap() {
                             //Ensure that hover entrance events aren't sent twice
-                            if window.hovered_region_ids.insert(region.id()) {
+                            if let Err(ix) = window.hovered_region_ids.binary_search(&region.id()) {
+                                window.hovered_region_ids.insert(ix, region.id());
+                            }
+                            // window.hovered_region_ids.insert(region.id());
+                            if !prev_hovered_regions.contains(&region.id()) {
                                 valid_regions.push(region.clone());
                                 if region.notify_on_hover {
                                     notified_views.insert(region.id().view_id());
@@ -690,7 +695,7 @@ impl<'a> WindowContext<'a> {
                             }
                         } else {
                             // Ensure that hover exit events aren't sent twice
-                            if window.hovered_region_ids.remove(&region.id()) {
+                            if prev_hovered_regions.contains(&region.id()) {
                                 valid_regions.push(region.clone());
                                 if region.notify_on_hover {
                                     notified_views.insert(region.id().view_id());
diff --git a/crates/gpui/src/scene/mouse_region.rs b/crates/gpui/src/scene/mouse_region.rs
index ca2cc04b9d1cf75c54ee9593705172f93c6f8ec4..cf39ac782fca327a627105a8ebe88f0f29f95ca5 100644
--- a/crates/gpui/src/scene/mouse_region.rs
+++ b/crates/gpui/src/scene/mouse_region.rs
@@ -177,7 +177,7 @@ impl MouseRegion {
     }
 }
 
-#[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
+#[derive(Copy, Clone, Eq, PartialEq, Hash, Debug, PartialOrd, Ord)]
 pub struct MouseRegionId {
     view_id: usize,
     tag: TypeId,