feat(infrastructure): introduce ErrorContext for tracking errors across threads (#83)

* Implement ErrorContext for tracking errors across threads

* reorder Instruction and ErrorContext

* Add ContextType, AppContext, ScreenContext, PtyContext

* Use ArrayVec in ErrorContext

* increase MAX_THREAD_CALL_STACK to 6

* Custom implement Debug for ErrorContext ad ContextType and color output

* Use os_input instead of println!()

* Use array instead of ArrayVec and some cleanup

* Introduce SenderWithContext

* Keep arrayvec at v0.5.1

6 files changed, 299 insertions, 53 deletions

diff --git a/src/errors.rs b/src/errors.rs
index 437db0dd..8478969d 100644
--- a/src/errors.rs
+++ b/src/errors.rs
@@ -1,10 +1,17 @@
-use crate::AppInstruction;
+use crate::pty_bus::PtyInstruction;
+use crate::screen::ScreenInstruction;
+use crate::{AppInstruction, SenderWithContext, OPENCALLS};
 use backtrace::Backtrace;
+use std::fmt::{Display, Error, Formatter};
 use std::panic::PanicInfo;
-use std::sync::mpsc::SyncSender;
 use std::{process, thread};
 
-pub fn handle_panic(info: &PanicInfo<'_>, send_app_instructions: &SyncSender<AppInstruction>) {
+const MAX_THREAD_CALL_STACK: usize = 6;
+
+pub fn handle_panic(
+    info: &PanicInfo<'_>,
+    send_app_instructions: &SenderWithContext<AppInstruction>,
+) {
     let backtrace = Backtrace::new();
     let thread = thread::current();
     let thread = thread.name().unwrap_or("unnamed");
@@ -14,9 +21,12 @@ pub fn handle_panic(info: &PanicInfo<'_>, send_app_instructions: &SyncSender<App
         None => info.payload().downcast_ref::<String>().map(|s| &**s),
     };
 
+    let err_ctx = OPENCALLS.with(|ctx| *ctx.borrow());
+
     let backtrace = match (info.location(), msg) {
         (Some(location), Some(msg)) => format!(
-            "\nthread '{}' panicked at '{}': {}:{}\n{:?}",
+            "{}\n\u{1b}[0;0mError: \u{1b}[0;31mthread '{}' panicked at '{}': {}:{}\n\u{1b}[0;0m{:?}",
+            err_ctx,
             thread,
             msg,
             location.file(),
@@ -24,17 +34,21 @@ pub fn handle_panic(info: &PanicInfo<'_>, send_app_instructions: &SyncSender<App
             backtrace
         ),
         (Some(location), None) => format!(
-            "\nthread '{}' panicked: {}:{}\n{:?}",
+            "{}\n\u{1b}[0;0mError: \u{1b}[0;31mthread '{}' panicked: {}:{}\n\u{1b}[0;0m{:?}",
+            err_ctx,
             thread,
             location.file(),
             location.line(),
             backtrace
         ),
         (None, Some(msg)) => format!(
-            "\nthread '{}' panicked at '{}'\n{:?}",
-            thread, msg, backtrace
+            "{}\n\u{1b}[0;0mError: \u{1b}[0;31mthread '{}' panicked at '{}'\n\u{1b}[0;0m{:?}",
+            err_ctx, thread, msg, backtrace
+        ),
+        (None, None) => format!(
+            "{}\n\u{1b}[0;0mError: \u{1b}[0;31mthread '{}' panicked\n\u{1b}[0;0m{:?}",
+            err_ctx, thread, backtrace
         ),
-        (None, None) => format!("\nthread '{}' panicked\n{:?}", thread, backtrace),
     };
 
     if thread == "main" {
@@ -46,3 +60,165 @@ pub fn handle_panic(info: &PanicInfo<'_>, send_app_instructions: &SyncSender<App
             .unwrap();
     }
 }
+
+#[derive(Clone, Copy)]
+pub struct ErrorContext {
+    calls: [ContextType; MAX_THREAD_CALL_STACK],
+}
+
+impl ErrorContext {
+    pub fn new() -> Self {
+        Self {
+            calls: [ContextType::Empty; MAX_THREAD_CALL_STACK],
+        }
+    }
+
+    pub fn add_call(&mut self, call: ContextType) {
+        for ctx in self.calls.iter_mut() {
+            if *ctx == ContextType::Empty {
+                *ctx = call;
+                break;
+            }
+        }
+        OPENCALLS.with(|ctx| *ctx.borrow_mut() = *self);
+    }
+}
+
+impl Display for ErrorContext {
+    fn fmt(&self, f: &mut Formatter) -> Result<(), Error> {
+        writeln!(f, "Originating Thread(s):")?;
+        for (index, ctx) in self.calls.iter().enumerate() {
+            if *ctx == ContextType::Empty {
+                break;
+            }
+            writeln!(f, "\u{1b}[0;0m{}. {}", index + 1, ctx)?;
+        }
+        Ok(())
+    }
+}
+
+#[derive(Copy, Clone, PartialEq)]
+pub enum ContextType {
+    Screen(ScreenContext),
+    Pty(PtyContext),
+    App(AppContext),
+    IPCServer,
+    StdinHandler,
+    AsyncTask,
+    Empty,
+}
+
+impl Display for ContextType {
+    fn fmt(&self, f: &mut Formatter) -> Result<(), Error> {
+        let purple = "\u{1b}[1;35m";
+        let green = "\u{1b}[0;32m";
+        match *self {
+            ContextType::Screen(c) => write!(f, "{}screen_thread: {}{:?}", purple, green, c),
+            ContextType::Pty(c) => write!(f, "{}pty_thread: {}{:?}", purple, green, c),
+            ContextType::App(c) => write!(f, "{}main_thread: {}{:?}", purple, green, c),
+            ContextType::IPCServer => write!(f, "{}ipc_server: {}AcceptInput", purple, green),
+            ContextType::StdinHandler => {
+                write!(f, "{}stdin_handler_thread: {}AcceptInput", purple, green)
+            }
+            ContextType::AsyncTask => {
+                write!(f, "{}stream_terminal_bytes: {}AsyncTask", purple, green)
+            }
+            ContextType::Empty => write!(f, ""),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum ScreenContext {
+    HandlePtyEvent,
+    Render,
+    NewPane,
+    HorizontalSplit,
+    VerticalSplit,
+    WriteCharacter,
+    ResizeLeft,
+    ResizeRight,
+    ResizeDown,
+    ResizeUp,
+    MoveFocus,
+    MoveFocusLeft,
+    MoveFocusDown,
+    MoveFocusUp,
+    MoveFocusRight,
+    Quit,
+    ScrollUp,
+    ScrollDown,
+    ClearScroll,
+    CloseFocusedPane,
+    ToggleActiveTerminalFullscreen,
+    ClosePane,
+    ApplyLayout,
+}
+
+impl From<&ScreenInstruction> for ScreenContext {
+    fn from(screen_instruction: &ScreenInstruction) -> Self {
+        match *screen_instruction {
+            ScreenInstruction::Pty(..) => ScreenContext::HandlePtyEvent,
+            ScreenInstruction::Render => ScreenContext::Render,
+            ScreenInstruction::NewPane(_) => ScreenContext::NewPane,
+            ScreenInstruction::HorizontalSplit(_) => ScreenContext::HorizontalSplit,
+            ScreenInstruction::VerticalSplit(_) => ScreenContext::VerticalSplit,
+            ScreenInstruction::WriteCharacter(_) => ScreenContext::WriteCharacter,
+            ScreenInstruction::ResizeLeft => ScreenContext::ResizeLeft,
+            ScreenInstruction::ResizeRight => ScreenContext::ResizeRight,
+            ScreenInstruction::ResizeDown => ScreenContext::ResizeDown,
+            ScreenInstruction::ResizeUp => ScreenContext::ResizeUp,
+            ScreenInstruction::MoveFocus => ScreenContext::MoveFocus,
+            ScreenInstruction::MoveFocusLeft => ScreenContext::MoveFocusLeft,
+            ScreenInstruction::MoveFocusDown => ScreenContext::MoveFocusDown,
+            ScreenInstruction::MoveFocusUp => ScreenContext::MoveFocusUp,
+            ScreenInstruction::MoveFocusRight => ScreenContext::MoveFocusRight,
+            ScreenInstruction::Quit => ScreenContext::Quit,
+            ScreenInstruction::ScrollUp => ScreenContext::ScrollUp,
+            ScreenInstruction::ScrollDown => ScreenContext::ScrollDown,
+            ScreenInstruction::ClearScroll => ScreenContext::ClearScroll,
+            ScreenInstruction::CloseFocusedPane => ScreenContext::CloseFocusedPane,
+            ScreenInstruction::ToggleActiveTerminalFullscreen => {
+                ScreenContext::ToggleActiveTerminalFullscreen
+            }
+            ScreenInstruction::ClosePane(_) => ScreenContext::ClosePane,
+            ScreenInstruction::ApplyLayout(_) => ScreenContext::ApplyLayout,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum PtyContext {
+    SpawnTerminal,
+    SpawnTerminalVertically,
+    SpawnTerminalHorizontally,
+    ClosePane,
+    Quit,
+}
+
+impl From<&PtyInstruction> for PtyContext {
+    fn from(pty_instruction: &PtyInstruction) -> Self {
+        match *pty_instruction {
+            PtyInstruction::SpawnTerminal(_) => PtyContext::SpawnTerminal,
+            PtyInstruction::SpawnTerminalVertically(_) => PtyContext::SpawnTerminalVertically,
+            PtyInstruction::SpawnTerminalHorizontally(_) => PtyContext::SpawnTerminalHorizontally,
+            PtyInstruction::ClosePane(_) => PtyContext::ClosePane,
+            PtyInstruction::Quit => PtyContext::Quit,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum AppContext {
+    Exit,
+    Error,
+}
+
+impl From<&AppInstruction> for AppContext {
+    fn from(app_instruction: &AppInstruction) -> Self {
+        match *app_instruction {
+            AppInstruction::Exit => AppContext::Exit,
+            AppInstruction::Error(_) => AppContext::Error,
+        }
+    }
+}
diff --git a/src/input.rs b/src/input.rs
index ea2c4d41..6d82f4f9 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -1,28 +1,27 @@
 /// Module for handling input
-use std::sync::mpsc::{Sender, SyncSender};
-
+use crate::errors::ContextType;
 use crate::os_input_output::OsApi;
 use crate::pty_bus::PtyInstruction;
 use crate::screen::ScreenInstruction;
-use crate::AppInstruction;
 use crate::CommandIsExecuting;
+use crate::{AppInstruction, SenderWithContext, OPENCALLS};
 
 struct InputHandler {
     mode: InputMode,
     os_input: Box<dyn OsApi>,
     command_is_executing: CommandIsExecuting,
-    send_screen_instructions: Sender<ScreenInstruction>,
-    send_pty_instructions: Sender<PtyInstruction>,
-    send_app_instructions: SyncSender<AppInstruction>,
+    send_screen_instructions: SenderWithContext<ScreenInstruction>,
+    send_pty_instructions: SenderWithContext<PtyInstruction>,
+    send_app_instructions: SenderWithContext<AppInstruction>,
 }
 
 impl InputHandler {
     fn new(
         os_input: Box<dyn OsApi>,
         command_is_executing: CommandIsExecuting,
-        send_screen_instructions: Sender<ScreenInstruction>,
-        send_pty_instructions: Sender<PtyInstruction>,
-        send_app_instructions: SyncSender<AppInstruction>,
+        send_screen_instructions: SenderWithContext<ScreenInstruction>,
+        send_pty_instructions: SenderWithContext<PtyInstruction>,
+        send_app_instructions: SenderWithContext<AppInstruction>,
     ) -> Self {
         InputHandler {
             mode: InputMode::Normal,
@@ -36,6 +35,11 @@ impl InputHandler {
 
     /// Main event loop
     fn get_input(&mut self) {
+        let mut err_ctx = OPENCALLS.with(|ctx| *ctx.borrow());
+        err_ctx.add_call(ContextType::StdinHandler);
+        self.send_pty_instructions.update(err_ctx);
+        self.send_app_instructions.update(err_ctx);
+        self.send_screen_instructions.update(err_ctx);
         loop {
             match self.mode {
                 InputMode::Normal => self.read_normal_mode(),
@@ -263,9 +267,9 @@ pub enum InputMode {
 pub fn input_loop(
     os_input: Box<dyn OsApi>,
     command_is_executing: CommandIsExecuting,
-    send_screen_instructions: Sender<ScreenInstruction>,
-    send_pty_instructions: Sender<PtyInstruction>,
-    send_app_instructions: SyncSender<AppInstruction>,
+    send_screen_instructions: SenderWithContext<ScreenInstruction>,
+    send_pty_instructions: SenderWithContext<PtyInstruction>,
+    send_app_instructions: SenderWithContext<AppInstruction>,
 ) {
     let _handler = InputHandler::new(
         os_input,
diff --git a/src/main.rs b/src/main.rs
index 0ad09ed0..27deb093 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -15,13 +15,14 @@ mod utils;
 use std::io::Write;
 use std::os::unix::net::UnixStream;
 use std::path::PathBuf;
-use std::sync::mpsc::{channel, sync_channel, Receiver, Sender, SyncSender};
+use std::sync::mpsc::{channel, sync_channel, Receiver, SendError, Sender, SyncSender};
 use std::thread;
 
 use serde::{Deserialize, Serialize};
 use structopt::StructOpt;
 
 use crate::command_is_executing::CommandIsExecuting;
+use crate::errors::{AppContext, ContextType, ErrorContext, PtyContext, ScreenContext};
 use crate::input::input_loop;
 use crate::layout::Layout;
 use crate::os_input_output::{get_os_input, OsApi};
@@ -31,6 +32,9 @@ use crate::utils::{
     consts::{MOSAIC_IPC_PIPE, MOSAIC_TMP_DIR, MOSAIC_TMP_LOG_DIR},
     logging::*,
 };
+use std::cell::RefCell;
+
+thread_local!(static OPENCALLS: RefCell<ErrorContext> = RefCell::new(ErrorContext::new()));
 
 #[derive(Serialize, Deserialize, Debug)]
 enum ApiCommand {
@@ -40,6 +44,38 @@ enum ApiCommand {
     MoveFocus,
 }
 
+#[derive(Clone)]
+enum SenderType<T: Clone> {
+    Sender(Sender<(T, ErrorContext)>),
+    SyncSender(SyncSender<(T, ErrorContext)>),
+}
+
+#[derive(Clone)]
+pub struct SenderWithContext<T: Clone> {
+    err_ctx: ErrorContext,
+    sender: SenderType<T>,
+}
+
+impl<T: Clone> SenderWithContext<T> {
+    fn new(err_ctx: ErrorContext, sender: SenderType<T>) -> Self {
+        Self { err_ctx, sender }
+    }
+
+    pub fn send(&self, event: T) -> Result<(), SendError<(T, ErrorContext)>> {
+        match self.sender {
+            SenderType::Sender(ref s) => s.send((event, self.err_ctx)),
+            SenderType::SyncSender(ref s) => s.send((event, self.err_ctx)),
+        }
+    }
+
+    pub fn update(&mut self, new_ctx: ErrorContext) {
+        self.err_ctx = new_ctx;
+    }
+}
+
+unsafe impl<T: Clone> Send for SenderWithContext<T> {}
+unsafe impl<T: Clone> Sync for SenderWithContext<T> {}
+
 #[derive(StructOpt, Debug, Default)]
 #[structopt(name = "mosaic")]
 pub struct Opt {
@@ -94,6 +130,7 @@ pub fn main() {
     }
 }
 
+#[derive(Clone)]
 pub enum AppInstruction {
     Exit,
     Error(String),
@@ -107,17 +144,24 @@ pub fn start(mut os_input: Box<dyn OsApi>, opts: Opt) {
     let full_screen_ws = os_input.get_terminal_size_using_fd(0);
     os_input.into_raw_mode(0);
     let (send_screen_instructions, receive_screen_instructions): (
-        Sender<ScreenInstruction>,
-        Receiver<ScreenInstruction>,
+        Sender<(ScreenInstruction, ErrorContext)>,
+        Receiver<(ScreenInstruction, ErrorContext)>,
     ) = channel();
+    let err_ctx = OPENCALLS.with(|ctx| *ctx.borrow());
+    let mut send_screen_instructions =
+        SenderWithContext::new(err_ctx, SenderType::Sender(send_screen_instructions));
     let (send_pty_instructions, receive_pty_instructions): (
-        Sender<PtyInstruction>,
-        Receiver<PtyInstruction>,
+        Sender<(PtyInstruction, ErrorContext)>,
+        Receiver<(PtyInstruction, ErrorContext)>,
     ) = channel();
+    let mut send_pty_instructions =
+        SenderWithContext::new(err_ctx, SenderType::Sender(send_pty_instructions));
     let (send_app_instructions, receive_app_instructions): (
-        SyncSender<AppInstruction>,
-        Receiver<AppInstruction>,
+        SyncSender<(AppInstruction, ErrorContext)>,
+        Receiver<(AppInstruction, ErrorContext)>,
     ) = sync_channel(0);
+    let send_app_instructions =
+        SenderWithContext::new(err_ctx, SenderType::SyncSender(send_app_instructions));
     let mut screen = Screen::new(
         receive_screen_instructions,
         send_pty_instructions.clone(),
@@ -156,10 +200,12 @@ pub fn start(mut os_input: Box<dyn OsApi>, opts: Opt) {
                     }
 
                     loop {
-                        let event = pty_bus
+                        let (event, mut err_ctx) = pty_bus
                             .receive_pty_instructions
                             .recv()
                             .expect("failed to receive event on channel");
+                        err_ctx.add_call(ContextType::Pty(PtyContext::from(&event)));
+                        pty_bus.send_screen_instructions.update(err_ctx);
                         match event {
                             PtyInstruction::SpawnTerminal(file_to_open) => {
                                 pty_bus.spawn_terminal(file_to_open);
@@ -190,10 +236,13 @@ pub fn start(mut os_input: Box<dyn OsApi>, opts: Opt) {
             .spawn({
                 let mut command_is_executing = command_is_executing.clone();
                 move || loop {
-                    let event = screen
+                    let (event, mut err_ctx) = screen
                         .receiver
                         .recv()
                         .expect("failed to receive event on channel");
+                    err_ctx.add_call(ContextType::Screen(ScreenContext::from(&event)));
+                    screen.send_app_instructions.update(err_ctx);
+                    screen.send_pty_instructions.update(err_ctx);
                     match event {
                         ScreenInstruction::Pty(pid, vte_event) => {
                             screen.handle_pty_event(pid, vte_event);
@@ -388,12 +437,16 @@ pub fn start(mut os_input: Box<dyn OsApi>, opts: Opt) {
         .name("ipc_server".to_string())
         .spawn({
             use std::io::Read;
-            let send_pty_instructions = send_pty_instructions.clone();
-            let send_screen_instructions = send_screen_instructions.clone();
+            let mut send_pty_instructions = send_pty_instructions.clone();
+            let mut send_screen_instructions = send_screen_instructions.clone();
             move || {
                 std::fs::remove_file(MOSAIC_IPC_PIPE).ok();
                 let listener = std::os::unix::net::UnixListener::bind(MOSAIC_IPC_PIPE)
                     .expect("could not listen on ipc socket");
+                let mut err_ctx = OPENCALLS.with(|ctx| *ctx.borrow());
+                err_ctx.add_call(ContextType::IPCServer);
+                send_pty_instructions.update(err_ctx);
+                send_screen_instructions.update(err_ctx);
 
                 for stream in listener.incoming() {
                     match stream {
@@ -456,9 +509,13 @@ pub fn start(mut os_input: Box<dyn OsApi>, opts: Opt) {
 
     #[warn(clippy::never_loop)]
     loop {
-        let app_instruction = receive_app_instructions
+        let (app_instruction, mut err_ctx) = receive_app_instructions
             .recv()
             .expect("failed to receive app instruction on channel");
+
+        err_ctx.add_call(ContextType::App(AppContext::from(&app_instruction)));
+        send_screen_instructions.update(err_ctx);
+        send_pty_instructions.update(err_ctx);
         match app_instruction {
             AppInstruction::Exit => {
                 let _ = send_screen_instructions.send(ScreenInstruction::Quit);
@@ -466,10 +523,15 @@ pub fn start(mut os_input: Box<dyn OsApi>, opts: Opt) {
                 break;
             }
             AppInstruction::Error(backtrace) => {
-                os_input.unset_raw_mode(0);
-                println!("{}", backtrace);
                 let _ = send_screen_instructions.send(ScreenInstruction::Quit);
                 let _ = send_pty_instructions.send(PtyInstruction::Quit);
+                os_input.unset_raw_mode(0);
+                let goto_start_of_last_line = format!("\u{1b}[{};{}H", full_screen_ws.rows, 1);
+                let error = format!("{}\n{}", goto_start_of_last_line, backtrace);
+                let _ = os_input
+                    .get_stdout_writer()
+                    .write(error.as_bytes())
+                    .unwrap();
                 for thread_handler in active_threads {
                     let _ = thread_handler.join();
                 }
diff --git a/src/pty_bus.rs b/src/pty_bus.rs
index 078e3271..758271c3 100644
--- a/src/pty_bus.rs
+++ b/src/pty_bus.rs
@@ -4,15 +4,16 @@ use ::async_std::task::*;
 use ::std::collections::HashMap;
 use ::std::os::unix::io::RawFd;
 use ::std::pin::*;
-use ::std::sync::mpsc::{Receiver, Sender};
+use ::std::sync::mpsc::Receiver;
 use ::std::time::{Duration, Instant};
 use ::vte;
 use std::path::PathBuf;
 
+use crate::errors::{ContextType, ErrorContext};
 use crate::layout::Layout;
 use crate::os_input_output::OsApi;
 use crate::utils::logging::debug_to_file;
-use crate::ScreenInstruction;
+use crate::{ScreenInstruction, SenderWithContext, OPENCALLS};
 
 pub struct ReadFromPid {
     pid: RawFd,
@@ -75,11 +76,11 @@ pub enum VteEvent {
 
 struct VteEventSender {
     id: RawFd,
-    sender: Sender<ScreenInstruction>,
+    sender: SenderWithContext<ScreenInstruction>,
 }
 
 impl VteEventSender {
-    pub fn new(id: RawFd, sender: Sender<ScreenInstruction>) -> Self {
+    pub fn new(id: RawFd, sender: SenderWithContext<ScreenInstruction>) -> Self {
         VteEventSender { id, sender }
     }
 }
@@ -151,8 +152,8 @@ pub enum PtyInstruction {
 }
 
 pub struct PtyBus {
-    pub send_screen_instructions: Sender<ScreenInstruction>,
-    pub receive_pty_instructions: Receiver<PtyInstruction>,
+    pub send_screen_instructions: SenderWithContext<ScreenInstruction>,
+    pub receive_pty_instructions: Receiver<(PtyInstruction, ErrorContext)>,
     pub id_to_child_pid: HashMap<RawFd, RawFd>,
     os_input: Box<dyn OsApi>,
     debug_to_file: bool,
@@ -160,12 +161,15 @@ pub struct PtyBus {
 
 fn stream_terminal_bytes(
     pid: RawFd,
-    send_screen_instructions: Sender<ScreenInstruction>,
+    mut send_screen_instructions: SenderWithContext<ScreenInstruction>,
     os_input: Box<dyn OsApi>,
     debug: bool,
 ) {
+    let mut err_ctx = OPENCALLS.with(|ctx| *ctx.borrow());
     task::spawn({
         async move {
+            err_ctx.add_call(ContextType::AsyncTask);
+            send_screen_instructions.update(err_ctx);
             let mut vte_parser = vte::Parser::new();
             let mut vte_event_sender = VteEventSender::new(pid, send_screen_instructions.clone());
             let mut terminal_bytes = ReadFromPid::new(&pid, os_input);
@@ -233,8 +237,8 @@ fn stream_terminal_bytes(
 
 impl PtyBus {
     pub fn new(
-        receive_pty_instructions: Receiver<PtyInstruction>,
-        send_screen_instructions: Sender<ScreenInstruction>,
+        receive_pty_instructions: Receiver<(PtyInstruction, ErrorContext)>,
+        send_screen_instructions: SenderWithContext<ScreenInstruction>,
         os_input: Box<dyn OsApi>,
         debug_to_file: bool,
     ) -> Self {
diff --git a/src/screen.rs b/src/screen.rs
index e00cc0a9..79442a97 100644
--- a/src/screen.rs
+++ b/src/screen.rs
@@ -1,16 +1,16 @@
 use std::collections::{BTreeMap, HashSet};
 use std::io::Write;
 use std::os::unix::io::RawFd;
-use std::sync::mpsc::{Receiver, Sender, SyncSender};
+use std::sync::mpsc::Receiver;
 
 use crate::boundaries::Boundaries;
 use crate::boundaries::Rect;
+use crate::errors::ErrorContext;
 use crate::layout::Layout;
 use crate::os_input_output::OsApi;
 use crate::pty_bus::{PtyInstruction, VteEvent};
 use crate::terminal_pane::{PositionAndSize, TerminalPane};
-use crate::utils::logging::debug_log_to_file;
-use crate::AppInstruction;
+use crate::{AppInstruction, SenderWithContext};
 
 /*
  * Screen
@@ -78,10 +78,10 @@ pub enum ScreenInstruction {
 }
 
 pub struct Screen {
-    pub receiver: Receiver<ScreenInstruction>,
+    pub receiver: Receiver<(ScreenInstruction, ErrorContext)>,
     max_panes: Option<usize>,
-    send_pty_instructions: Sender<PtyInstruction>,
-    send_app_instructions: SyncSender<AppInstruction>,
+    pub send_pty_instructions: SenderWithContext<PtyInstruction>,
+    pub send_app_instructions: SenderWithContext<AppInstruction>,
     full_screen_ws: PositionAndSize,
     terminals: BTreeMap<RawFd, TerminalPane>, // BTreeMap because we need a predictable order when changing focus
     panes_to_hide: HashSet<RawFd>,
@@ -92,9 +92,9 @@ pub struct Screen {
 
 impl Screen {
     pub fn new(
-        receive_screen_instructions: Receiver<ScreenInstruction>,
-        send_pty_instructions: Sender<PtyInstruction>,
-        send_app_instructions: SyncSender<AppInstruction>,
+        receive_screen_instructions: Receiver<(ScreenInstruction, ErrorContext)>,
+        send_pty_instructions: SenderWithContext<PtyInstruction>,
+        send_app_instructions: SenderWithContext<AppInstruction>,
         full_screen_ws: &PositionAndSize,
         os_api: Box<dyn OsApi>,
         max_panes: Option<usize>,
diff --git a/src/utils/logging.rs b/src/utils/logging.rs
index 84a2da8f..05af455c 100644
--- a/src/utils/logging.rs
+++ b/src/utils/logging.rs
@@ -37,7 +37,7 @@ pub fn debug_log_to_file_without_newline(message: String) -> io::Result<()> {
     file.write_all(message.as_bytes())
 }
 
-pub fn debug_log_to_file_pid_3(message: String, pid: RawFd) -> io::Result<()> {
+pub fn _debug_log_to_file_pid_3(message: String, pid: RawFd) -> io::Result<()> {
     if pid == 3 {
         debug_log_to_file(message)
     } else {