refactor(term): avoid rendering during key event handling if possible

ymgyt · May 30, 2024 · db42f5c · db42f5c
1 parent bd428f1
commit db42f5c
Show file tree

Hide file tree

Showing 5 changed files with 59 additions and 17 deletions.
diff --git a/crates/synd_term/src/application/event/key_handlers.rs b/crates/synd_term/src/application/event/key_handlers.rs
@@ -1,4 +1,4 @@
-use std::{cell::RefCell, rc::Rc};
+use std::{cell::RefCell, ops::ControlFlow, rc::Rc};
 
 use crossterm::event::KeyEvent;
 
@@ -49,11 +49,16 @@ impl KeyHandlers {
     }
 
     pub fn handle(&mut self, event: KeyEvent) -> KeyEventResult {
-        for handler in self.handlers.iter_mut().rev() {
-            if let KeyEventResult::Consumed(r) = handler.handle(&event) {
-                return KeyEventResult::Consumed(r);
+        match self.handlers.iter_mut().rev().try_for_each(|h| {
+            let result = h.handle(&event);
+            if result.is_consumed() {
+                ControlFlow::Break(result)
+            } else {
+                ControlFlow::Continue(())
             }
+        }) {
+            ControlFlow::Break(consumed) => consumed,
+            ControlFlow::Continue(()) => KeyEventResult::Ignored,
         }
-        KeyEventResult::Ignored
     }
 }
diff --git a/crates/synd_term/src/application/event/mod.rs b/crates/synd_term/src/application/event/mod.rs
@@ -4,6 +4,32 @@ mod key_handlers;
 pub use key_handlers::{KeyHandler, KeyHandlers};
 
 pub(crate) enum KeyEventResult {
-    Consumed(Option<Command>),
+    Consumed {
+        command: Option<Command>,
+        should_render: bool,
+    },
     Ignored,
 }
+
+impl KeyEventResult {
+    pub(super) fn is_consumed(&self) -> bool {
+        matches!(self, KeyEventResult::Consumed { .. })
+    }
+
+    pub(crate) fn consumed(command: Command) -> Self {
+        KeyEventResult::Consumed {
+            command: Some(command),
+            should_render: false,
+        }
+    }
+
+    pub(crate) fn should_render(self, should_render: bool) -> Self {
+        match self {
+            KeyEventResult::Consumed { command, .. } => KeyEventResult::Consumed {
+                command,
+                should_render,
+            },
+            KeyEventResult::Ignored => KeyEventResult::Ignored,
+        }
+    }
+}
diff --git a/crates/synd_term/src/application/mod.rs b/crates/synd_term/src/application/mod.rs
@@ -619,9 +619,12 @@ impl Application {
                 self.reset_idle_timer();
 
                 match self.key_handlers.handle(key) {
-                    KeyEventResult::Consumed(cmd) => {
-                        self.should_render();
-                        cmd
+                    KeyEventResult::Consumed {
+                        command,
+                        should_render,
+                    } => {
+                        should_render.then(|| self.should_render());
+                        command
                     }
                     KeyEventResult::Ignored => None,
                 }

diff --git a/crates/synd_term/src/keymap/mod.rs b/crates/synd_term/src/keymap/mod.rs
@@ -1,4 +1,4 @@
-use std::collections::HashMap;
+use std::{collections::HashMap, ops::ControlFlow};
 
 use anyhow::{anyhow, bail};
 use crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
@@ -129,12 +129,20 @@ impl Keymaps {
     }
 
     pub fn search(&mut self, event: &KeyEvent) -> KeyEventResult {
-        for keymap in self.keymaps.iter_mut().rev().filter(|k| k.enable) {
-            if let Some(cmd) = keymap.search(event) {
-                return KeyEventResult::Consumed(Some(cmd));
-            }
+        match self
+            .keymaps
+            .iter_mut()
+            .rev()
+            .filter(|k| k.enable)
+            .try_for_each(|keymap| match keymap.search(event) {
+                Some(command) => {
+                    ControlFlow::Break(KeyEventResult::consumed(command).should_render(true))
+                }
+                None => ControlFlow::Continue(()),
+            }) {
+            ControlFlow::Break(r) => r,
+            ControlFlow::Continue(()) => KeyEventResult::Ignored,
         }
-        KeyEventResult::Ignored
     }
 }
 

diff --git a/crates/synd_term/src/ui/widgets/prompt.rs b/crates/synd_term/src/ui/widgets/prompt.rs
@@ -58,14 +58,14 @@ impl Prompt {
                 let pos = self.move_cursor(Move::BackwardChar(1));
                 self.line.replace_range(pos..self.cursor, "");
                 self.cursor = pos;
-                KeyEventResult::Consumed(Some(Command::PromptChanged))
+                KeyEventResult::consumed(Command::PromptChanged).should_render(true)
             }
             KeyEvent {
                 code: KeyCode::Char(c),
                 ..
             } => {
                 self.insert_char(*c);
-                KeyEventResult::Consumed(Some(Command::PromptChanged))
+                KeyEventResult::consumed(Command::PromptChanged).should_render(true)
             }
             _ => KeyEventResult::Ignored,
         }