chore: Fix some violations of 'needless_pass_by_ref_mut' lint (#18795)

While this lint is allow-by-default, it seems pretty useful to get rid
of mutable borrows when they're not needed.

Closes #ISSUE

Release Notes:

- N/A

crates/client/src/client.rs

@@ -394,7 +394,7 @@ pub struct PendingEntitySubscription<T: 'static> {
 }
 
 impl<T: 'static> PendingEntitySubscription<T> {
-    pub fn set_model(mut self, model: &Model<T>, cx: &mut AsyncAppContext) -> Subscription {
+    pub fn set_model(mut self, model: &Model<T>, cx: &AsyncAppContext) -> Subscription {
         self.consumed = true;
         let mut handlers = self.client.handler_set.lock();
         let id = (TypeId::of::<T>(), self.remote_id);

crates/client/src/telemetry.rs

@@ -288,7 +288,7 @@ impl Telemetry {
         system_id: Option<String>,
         installation_id: Option<String>,
         session_id: String,
-        cx: &mut AppContext,
+        cx: &AppContext,
     ) {
         let mut state = self.state.lock();
         state.system_id = system_id.map(|id| id.into());

crates/client/src/user.rs

@@ -138,7 +138,7 @@ enum UpdateContacts {
 }
 
 impl UserStore {
-    pub fn new(client: Arc<Client>, cx: &mut ModelContext<Self>) -> Self {
+    pub fn new(client: Arc<Client>, cx: &ModelContext<Self>) -> Self {
         let (mut current_user_tx, current_user_rx) = watch::channel();
         let (update_contacts_tx, mut update_contacts_rx) = mpsc::unbounded();
         let rpc_subscriptions = vec![
@@ -310,7 +310,7 @@ impl UserStore {
     fn update_contacts(
         &mut self,
         message: UpdateContacts,
-        cx: &mut ModelContext<Self>,
+        cx: &ModelContext<Self>,
     ) -> Task<Result<()>> {
         match message {
             UpdateContacts::Wait(barrier) => {
@@ -525,9 +525,9 @@ impl UserStore {
     }
 
     pub fn dismiss_contact_request(
-        &mut self,
+        &self,
         requester_id: u64,
-        cx: &mut ModelContext<Self>,
+        cx: &ModelContext<Self>,
     ) -> Task<Result<()>> {
         let client = self.client.upgrade();
         cx.spawn(move |_, _| async move {
@@ -573,7 +573,7 @@ impl UserStore {
         })
     }
 
-    pub fn clear_contacts(&mut self) -> impl Future<Output = ()> {
+    pub fn clear_contacts(&self) -> impl Future<Output = ()> {
         let (tx, mut rx) = postage::barrier::channel();
         self.update_contacts_tx
             .unbounded_send(UpdateContacts::Clear(tx))
@@ -583,7 +583,7 @@ impl UserStore {
         }
     }
 
-    pub fn contact_updates_done(&mut self) -> impl Future<Output = ()> {
+    pub fn contact_updates_done(&self) -> impl Future<Output = ()> {
         let (tx, mut rx) = postage::barrier::channel();
         self.update_contacts_tx
             .unbounded_send(UpdateContacts::Wait(tx))
@@ -594,9 +594,9 @@ impl UserStore {
     }
 
     pub fn get_users(
-        &mut self,
+        &self,
         user_ids: Vec<u64>,
-        cx: &mut ModelContext<Self>,
+        cx: &ModelContext<Self>,
     ) -> Task<Result<Vec<Arc<User>>>> {
         let mut user_ids_to_fetch = user_ids.clone();
         user_ids_to_fetch.retain(|id| !self.users.contains_key(id));
@@ -629,9 +629,9 @@ impl UserStore {
     }
 
     pub fn fuzzy_search_users(
-        &mut self,
+        &self,
         query: String,
-        cx: &mut ModelContext<Self>,
+        cx: &ModelContext<Self>,
     ) -> Task<Result<Vec<Arc<User>>>> {
         self.load_users(proto::FuzzySearchUsers { query }, cx)
     }
@@ -640,11 +640,7 @@ impl UserStore {
         self.users.get(&user_id).cloned()
     }
 
-    pub fn get_user_optimistic(
-        &mut self,
-        user_id: u64,
-        cx: &mut ModelContext<Self>,
-    ) -> Option<Arc<User>> {
+    pub fn get_user_optimistic(&self, user_id: u64, cx: &ModelContext<Self>) -> Option<Arc<User>> {
         if let Some(user) = self.users.get(&user_id).cloned() {
             return Some(user);
         }
@@ -653,11 +649,7 @@ impl UserStore {
         None
     }
 
-    pub fn get_user(
-        &mut self,
-        user_id: u64,
-        cx: &mut ModelContext<Self>,
-    ) -> Task<Result<Arc<User>>> {
+    pub fn get_user(&self, user_id: u64, cx: &ModelContext<Self>) -> Task<Result<Arc<User>>> {
         if let Some(user) = self.users.get(&user_id).cloned() {
             return Task::ready(Ok(user));
         }
@@ -697,7 +689,7 @@ impl UserStore {
             .map(|accepted_tos_at| accepted_tos_at.is_some())
     }
 
-    pub fn accept_terms_of_service(&mut self, cx: &mut ModelContext<Self>) -> Task<Result<()>> {
+    pub fn accept_terms_of_service(&self, cx: &ModelContext<Self>) -> Task<Result<()>> {
         if self.current_user().is_none() {
             return Task::ready(Err(anyhow!("no current user")));
         };
@@ -726,9 +718,9 @@ impl UserStore {
     }
 
     fn load_users(
-        &mut self,
+        &self,
         request: impl RequestMessage<Response = UsersResponse>,
-        cx: &mut ModelContext<Self>,
+        cx: &ModelContext<Self>,
     ) -> Task<Result<Vec<Arc<User>>>> {
         let client = self.client.clone();
         cx.spawn(|this, mut cx| async move {