Refactor terminal to not use trait objects

crates/term/src/backends/channel.rs

@@ -64,11 +64,17 @@ impl Channel {
 }
 
 impl super::Backend for Channel {
-    fn with_term(&mut self, f: &mut dyn FnMut(&mut Term<EventListener>)) {
+    fn with_term<T, F>(&mut self, f: F) -> T
+    where
+        F: FnOnce(&mut Term<EventListener>) -> T,
+    {
         f(&mut self.term)
     }
 
-    fn with_event_recv(&mut self, f: &mut dyn FnMut(&mut Receiver<Event>)) {
+    fn with_event_recv<T, F>(&mut self, f: F) -> T
+    where
+        F: FnOnce(&mut Receiver<Event>) -> T,
+    {
         f(&mut self.event_reciever)
     }
 

crates/term/src/backends/mod.rs

@@ -32,7 +32,7 @@ pub use channel::Channel;
 pub use process::Process;
 
 #[derive(Clone)]
-pub(crate) struct EventListener(Sender<Event>);
+pub struct EventListener(Sender<Event>);
 
 impl alacritty_terminal::event::EventListener for EventListener {
     fn send_event(&self, event: Event) {
@@ -41,16 +41,22 @@ impl alacritty_terminal::event::EventListener for EventListener {
     }
 }
 
-pub(crate) trait Backend {
-    fn with_term(&mut self, f: &mut dyn FnMut(&mut alacritty_terminal::Term<EventListener>));
+pub trait Backend {
+    fn with_term<T, F>(&mut self, f: F) -> T
+    where
+        F: FnOnce(&mut alacritty_terminal::Term<EventListener>) -> T;
 
-    fn with_event_recv(&mut self, f: &mut dyn FnMut(&mut Receiver<Event>));
+    fn with_event_recv<T, F>(&mut self, f: F) -> T
+    where
+        F: FnOnce(&mut Receiver<Event>) -> T;
 
     fn size(&self) -> (usize, usize);
 
     fn resize(&mut self, rows: usize, cols: usize);
 
     fn update(&mut self) {}
 
+    fn send(&mut self, _msg: alacritty_terminal::event_loop::Msg) {}
+
     fn kill(&mut self) {}
 }

crates/term/src/backends/process.rs

@@ -83,12 +83,17 @@ impl Process {
 }
 
 impl super::Backend for Process {
-    fn with_term(&mut self, f: &mut dyn FnMut(&mut Term<EventListener>)) {
-        let mut lock = self.term.lock();
-        f(&mut lock)
+    fn with_term<T, F>(&mut self, f: F) -> T
+    where
+        F: FnOnce(&mut Term<EventListener>) -> T,
+    {
+        f(&mut self.term.lock())
     }
 
-    fn with_event_recv(&mut self, f: &mut dyn FnMut(&mut Receiver<Event>)) {
+    fn with_event_recv<T, F>(&mut self, f: F) -> T
+    where
+        F: FnOnce(&mut Receiver<Event>) -> T,
+    {
         f(&mut self.event_reciever)
     }
 
@@ -107,6 +112,10 @@ impl super::Backend for Process {
         self.term.lock().resize(TermSize::new(cols, rows))
     }
 
+    fn send(&mut self, msg: alacritty_terminal::event_loop::Msg) {
+        let _ = self.event_loop_sender.send(msg);
+    }
+
     fn kill(&mut self) {
         let _ = self.event_loop_sender.send(Msg::Shutdown);
     }

crates/term/src/widget/mod.rs

@@ -29,33 +29,42 @@ use crate::backends::Backend;
 mod theme;
 pub use theme::Theme;
 
-pub struct Terminal {
-    // REVIEW should we use generics or trait objects?
-    backend: Box<dyn Backend>,
+pub struct Terminal<T> {
+    backend: T,
     theme: Theme, // TODO convert into shared config (possibly do this in luminol-preferences)
     title: String,
 }
 
-impl Terminal {
-    fn new(backend: impl Backend + 'static) -> Self {
+pub type ProcessTerminal = Terminal<crate::backends::Process>;
+pub type ChannelTerminal = Terminal<crate::backends::Channel>;
+
+impl<T> Terminal<T> {
+    fn new(backend: T) -> Self {
         Self {
-            backend: Box::new(backend),
+            backend,
             theme: Theme::default(),
             title: "Luminol Terminal".to_string(),
         }
     }
+}
 
+impl ProcessTerminal {
     pub fn process(options: &alacritty_terminal::tty::Options) -> std::io::Result<Self> {
         crate::backends::Process::new(options).map(Self::new)
     }
+}
 
+impl ChannelTerminal {
     pub fn channel(recv: std::sync::mpsc::Receiver<u8>) -> Self {
         let backend = crate::backends::Channel::new(recv);
         Self::new(backend)
     }
 }
 
-impl Terminal {
+impl<T> Terminal<T>
+where
+    T: Backend,
+{
     pub fn title(&self) -> String {
         self.title.to_string()
     }
@@ -89,13 +98,13 @@ impl Terminal {
     }
 
     pub fn erase_scrollback(&mut self) {
-        self.backend.with_term(&mut |term| {
+        self.backend.with_term(|term| {
             term.grid_mut().clear_history();
         });
     }
 
     pub fn erase_scrollback_and_viewport(&mut self) {
-        self.backend.with_term(&mut |term| {
+        self.backend.with_term(|term| {
             term.grid_mut().clear_viewport();
         });
     }
@@ -107,7 +116,8 @@ impl Terminal {
     pub fn ui(&mut self, ui: &mut egui::Ui) -> color_eyre::Result<()> {
         self.backend.update();
 
-        self.backend.with_term(&mut |term| {
+        // TODO cache render jobs
+        let job = self.backend.with_term(|term| {
             let content = term.renderable_content();
 
             let mut job = egui::text::LayoutJob::default();
@@ -128,23 +138,26 @@ impl Terminal {
                     job.append("\n", 0.0, Default::default());
                 }
             }
-            let galley = ui.fonts(|f| f.layout_job(job));
-            let (response, painter) =
-                ui.allocate_painter(galley.rect.size(), egui::Sense::click_and_drag());
 
-            painter.rect_filled(
-                galley.rect.translate(response.rect.min.to_vec2()),
-                0.0,
-                egui::Color32::from_rgb(40, 39, 39),
-            );
+            job
+        });
 
-            painter.galley(response.rect.min, galley, egui::Color32::WHITE);
+        let galley = ui.fonts(|f| f.layout_job(job));
+        let (response, painter) =
+            ui.allocate_painter(galley.rect.size(), egui::Sense::click_and_drag());
 
-            if response.hovered() {
-                ui.output_mut(|o| o.mutable_text_under_cursor = true);
-                ui.ctx().set_cursor_icon(egui::CursorIcon::Text);
-            }
-        });
+        painter.rect_filled(
+            galley.rect.translate(response.rect.min.to_vec2()),
+            0.0,
+            egui::Color32::from_rgb(40, 39, 39),
+        );
+
+        painter.galley(response.rect.min, galley, egui::Color32::WHITE);
+
+        if response.hovered() {
+            ui.output_mut(|o| o.mutable_text_under_cursor = true);
+            ui.ctx().set_cursor_icon(egui::CursorIcon::Text);
+        }
 
         Ok(())
     }

crates/ui/src/windows/console.rs

@@ -23,7 +23,7 @@
 // Program grant you additional permission to convey the resulting work.
 
 pub struct Window {
-    term: luminol_term::widget::Terminal,
+    term: luminol_term::widget::ProcessTerminal,
 }
 
 impl Window {

src/app/log_window.rs

@@ -24,7 +24,7 @@
 
 pub struct LogWindow {
     pub(super) term_shown: bool,
-    term: luminol_term::widget::Terminal,
+    term: luminol_term::widget::ChannelTerminal,
     save_promise: Option<poll_promise::Promise<luminol_filesystem::Result<()>>>,
 }