Open editor in diff view (#2904)

Author: WaterWhisperer

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 * use [tombi](https://github.com/tombi-toml/tombi) for all toml file formatting
+* open the external editor from the status diff view [[@WaterWhisperer](https://github.com/WaterWhisperer)] ([#2805](https://github.com/gitui-org/gitui/issues/2805))
 
 ### Fixes
 * crash when opening submodule ([#2895](https://github.com/gitui-org/gitui/issues/2895))

src/components/diff.rs

@@ -152,6 +152,10 @@ impl DiffComponent {
 		(self.current.path.clone(), self.current.is_stage)
 	}
 	///
+	const fn can_edit_file(&self) -> bool {
+		!self.is_immutable && !self.current.path.is_empty()
+	}
+	///
 	pub fn clear(&mut self, pending: bool) {
 		self.current = Current::default();
 		self.diff = None;
@@ -770,6 +774,11 @@ impl Component for DiffComponent {
 		);
 
 		if !self.is_immutable {
+			out.push(CommandInfo::new(
+				strings::commands::edit_item(&self.key_config),
+				self.can_edit_file(),
+				self.focused() && self.can_edit_file(),
+			));
 			out.push(CommandInfo::new(
 				strings::commands::diff_hunk_remove(&self.key_config),
 				self.selected_hunk.is_some(),
@@ -876,6 +885,15 @@ impl Component for DiffComponent {
 				) {
 					self.diff_hunk_move_up_down(-1);
 					Ok(EventState::Consumed)
+				} else if key_match(e, self.key_config.keys.edit_file)
+					&& self.can_edit_file()
+				{
+					self.queue.push(
+						InternalEvent::OpenExternalEditor(Some(
+							self.current.path.clone(),
+						)),
+					);
+					Ok(EventState::Consumed)
 				} else if key_match(
 					e,
 					self.key_config.keys.stage_unstage_item,
@@ -945,7 +963,10 @@ impl Component for DiffComponent {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use crate::ui::style::Theme;
+	use crate::{
+		app::Environment, queue::InternalEvent, ui::style::Theme,
+	};
+	use crossterm::event::{Event, KeyCode, KeyEvent, KeyModifiers};
 	use std::io::Write;
 	use std::rc::Rc;
 	use tempfile::NamedTempFile;
@@ -1012,4 +1033,30 @@ mod tests {
 			);
 		}
 	}
+
+	#[test]
+	fn diff_component_opens_editor_for_current_file() {
+		let env = Environment::test_env();
+		let mut diff = DiffComponent::new(&env, false);
+
+		diff.focus(true);
+		diff.current.path = String::from("src/main.rs");
+
+		let event = Event::Key(KeyEvent::new(
+			KeyCode::Char('e'),
+			KeyModifiers::empty(),
+		));
+
+		assert!(matches!(
+			diff.event(&event).unwrap(),
+			EventState::Consumed
+		));
+
+		let event = env.queue.pop();
+		assert!(matches!(
+			event,
+			Some(InternalEvent::OpenExternalEditor(Some(path)))
+				if path == "src/main.rs"
+		));
+	}
 }