From b83003a8ecfb1538bbd026ba3eb776096d7359ac Mon Sep 17 00:00:00 2001
From: Fred Sundvik <fsundvik@gmail.com>
Date: Thu, 6 Jan 2022 16:52:09 +0200
Subject: [PATCH] Fix notification event ordering

Use a single thread instead of spawning a new task for each
notification. This makes sure they are processed in the correct order.
---
 src/bridge/handler.rs | 83 ++++++++++++++++++++++++++++---------------
 1 file changed, 55 insertions(+), 28 deletions(-)

diff --git a/src/bridge/handler.rs b/src/bridge/handler.rs
index ef77302..f4cc55f 100644
--- a/src/bridge/handler.rs
+++ b/src/bridge/handler.rs
@@ -1,8 +1,11 @@
 use async_trait::async_trait;
+use futures::lock::Mutex;
 use log::trace;
 use nvim_rs::{Handler, Neovim};
 use rmpv::Value;
-use tokio::task;
+use std::sync::mpsc::{channel, Receiver, Sender};
+use std::sync::Arc;
+use std::thread;
 
 #[cfg(windows)]
 use crate::bridge::ui_commands::{ParallelCommand, UiCommand};
@@ -14,12 +17,54 @@ use crate::{
     settings::SETTINGS,
 };
 
+struct NotificationEvent {
+    event_name: String,
+    arguments: Vec<Value>,
+}
+
 #[derive(Clone)]
-pub struct NeovimHandler {}
+pub struct NeovimHandler {
+    sender: Arc<Mutex<Sender<NotificationEvent>>>,
+}
 
 impl NeovimHandler {
     pub fn new() -> Self {
-        Self {}
+        let (sender, receiver): (Sender<NotificationEvent>, Receiver<NotificationEvent>) =
+            channel();
+        thread::spawn(|| {
+            for event in receiver {
+                match event.event_name.as_ref() {
+                    "redraw" => {
+                        for events in event.arguments {
+                            let parsed_events = parse_redraw_event(events)
+                                .unwrap_or_explained_panic("Could not parse event from neovim");
+
+                            for parsed_event in parsed_events {
+                                EVENT_AGGREGATOR
+                                    .send(EditorCommand::NeovimRedrawEvent(parsed_event));
+                            }
+                        }
+                    }
+                    "setting_changed" => {
+                        SETTINGS.handle_changed_notification(event.arguments);
+                    }
+                    #[cfg(windows)]
+                    "neovide.register_right_click" => {
+                        EVENT_AGGREGATOR
+                            .send(UiCommand::Parallel(ParallelCommand::RegisterRightClick));
+                    }
+                    #[cfg(windows)]
+                    "neovide.unregister_right_click" => {
+                        EVENT_AGGREGATOR
+                            .send(UiCommand::Parallel(ParallelCommand::UnregisterRightClick));
+                    }
+                    _ => {}
+                }
+            }
+        });
+        Self {
+            sender: Arc::new(Mutex::new(sender)),
+        }
     }
 }
 
@@ -34,30 +79,12 @@ impl Handler for NeovimHandler {
         _neovim: Neovim<TxWrapper>,
     ) {
         trace!("Neovim notification: {:?}", &event_name);
-
-        task::spawn_blocking(move || match event_name.as_ref() {
-            "redraw" => {
-                for events in arguments {
-                    let parsed_events = parse_redraw_event(events)
-                        .unwrap_or_explained_panic("Could not parse event from neovim");
-
-                    for parsed_event in parsed_events {
-                        EVENT_AGGREGATOR.send(EditorCommand::NeovimRedrawEvent(parsed_event));
-                    }
-                }
-            }
-            "setting_changed" => {
-                SETTINGS.handle_changed_notification(arguments);
-            }
-            #[cfg(windows)]
-            "neovide.register_right_click" => {
-                EVENT_AGGREGATOR.send(UiCommand::Parallel(ParallelCommand::RegisterRightClick));
-            }
-            #[cfg(windows)]
-            "neovide.unregister_right_click" => {
-                EVENT_AGGREGATOR.send(UiCommand::Parallel(ParallelCommand::UnregisterRightClick));
-            }
-            _ => {}
-        });
+        let sender = self.sender.lock().await;
+        sender
+            .send(NotificationEvent {
+                event_name,
+                arguments,
+            })
+            .ok();
     }
 }