remote projects: Allow reusing window (#11058)

Release Notes:

- Allow reusing the window when opening a remote project from the recent
projects picker
- Fixed an issue, which would not let you rejoin a remote project after
disconnecting from it for the first time

---------

Co-authored-by: Conrad <conrad@zed.dev>
Co-authored-by: Remco <djsmits12@gmail.com>

crates/semantic_index/src/semantic_index.rs

@@ -9,8 +9,8 @@ use fs::Fs;
 use futures::stream::StreamExt;
 use futures_batch::ChunksTimeoutStreamExt;
 use gpui::{
-    AppContext, AsyncAppContext, Context, EntityId, EventEmitter, Global, Model, ModelContext,
-    Subscription, Task, WeakModel,
+    AppContext, AsyncAppContext, BorrowAppContext, Context, Entity, EntityId, EventEmitter, Global,
+    Model, ModelContext, Subscription, Task, WeakModel,
 };
 use heed::types::{SerdeBincode, Str};
 use language::LanguageRegistry;
@@ -68,6 +68,18 @@ impl SemanticIndex {
         project: Model<Project>,
         cx: &mut AppContext,
     ) -> Model<ProjectIndex> {
+        let project_weak = project.downgrade();
+        project.update(cx, move |_, cx| {
+            cx.on_release(move |_, cx| {
+                if cx.has_global::<SemanticIndex>() {
+                    cx.update_global::<SemanticIndex, _>(|this, _| {
+                        this.project_indices.remove(&project_weak);
+                    })
+                }
+            })
+            .detach();
+        });
+
         self.project_indices
             .entry(project.downgrade())
             .or_insert_with(|| {
@@ -86,7 +98,7 @@ impl SemanticIndex {
 
 pub struct ProjectIndex {
     db_connection: heed::Env,
-    project: Model<Project>,
+    project: WeakModel<Project>,
     worktree_indices: HashMap<EntityId, WorktreeIndexHandle>,
     language_registry: Arc<LanguageRegistry>,
     fs: Arc<dyn Fs>,
@@ -116,7 +128,7 @@ impl ProjectIndex {
         let fs = project.read(cx).fs().clone();
         let mut this = ProjectIndex {
             db_connection,
-            project: project.clone(),
+            project: project.downgrade(),
             worktree_indices: HashMap::default(),
             language_registry,
             fs,
@@ -143,8 +155,11 @@ impl ProjectIndex {
     }
 
     fn update_worktree_indices(&mut self, cx: &mut ModelContext<Self>) {
-        let worktrees = self
-            .project
+        let Some(project) = self.project.upgrade() else {
+            return;
+        };
+
+        let worktrees = project
             .read(cx)
             .visible_worktrees(cx)
             .filter_map(|worktree| {