Use select macro for event handling

Author: MitMaro

src/components/help.rs

@@ -5,8 +5,9 @@ use unicode_segmentation::UnicodeSegmentation;
 
 use crate::{
 	display::DisplayColor,
-	first,
 	input::{Event, InputOptions, StandardEvent},
+	process::Results,
+	select,
 	util::handle_view_data_scroll,
 	view::{LineSegment, ViewData, ViewLine},
 };
@@ -87,15 +88,19 @@ impl Help {
 		(self.is_active() || event == Event::Standard(StandardEvent::Help)).then_some(event)
 	}
 
-	pub(crate) fn handle_event(&mut self, event: Event, view_state: &crate::view::State) {
-		let mut event_handler = || {
-			match event {
-				Event::Key(_) | Event::Standard(StandardEvent::Help) => self.active = false,
-				_ => {},
-			}
-			Some(())
-		};
-		first!(|| handle_view_data_scroll(event, view_state), event_handler);
+	pub(crate) fn handle_event(&mut self, event: Event, view_state: &crate::view::State) -> Option<Results> {
+		self.is_active().then(|| {
+			select!(
+				default || {
+					match event {
+						Event::Key(_) | Event::Standard(StandardEvent::Help) => self.active = false,
+						_ => {},
+					}
+					Results::new()
+				},
+				|| handle_view_data_scroll(event, view_state)
+			)
+		})
 	}
 
 	pub(crate) fn set_active(&mut self) {

src/components/help/tests.rs

@@ -9,7 +9,9 @@ use crate::{
 
 fn handle_event(help: &mut Help, event: Event) {
 	let evt = help.read_event(event).unwrap_or(event);
-	with_view_state(|context| help.handle_event(evt, &context.state));
+	with_view_state(|context| {
+		let _result = help.handle_event(evt, &context.state);
+	});
 }
 
 #[test]

src/modules/error.rs

@@ -6,6 +6,7 @@ use crate::{
 	input::{Event, InputOptions},
 	module::{Module, State},
 	process::Results,
+	select,
 	util::handle_view_data_scroll,
 	view::{LineSegment, RenderContext, ViewData, ViewLine},
 };
@@ -34,13 +35,16 @@ impl Module for Error {
 	}
 
 	fn handle_event(&mut self, event: Event, view_state: &crate::view::State) -> Results {
-		let mut results = Results::new();
-		if handle_view_data_scroll(event, view_state).is_none() {
-			if let Event::Key(_) = event {
-				results.state(self.return_state);
-			}
-		}
-		results
+		select!(
+			default || {
+				let mut results = Results::new();
+				if let Event::Key(_) = event {
+					results.state(self.return_state);
+				}
+				results
+			},
+			|| handle_view_data_scroll(event, view_state)
+		)
 	}
 
 	fn handle_error(&mut self, error: &anyhow::Error) -> Results {

src/modules/list.rs

@@ -117,8 +117,8 @@ impl Module for List {
 					ListState::Edit => self.handle_edit_mode_input(event),
 				}
 			},
-			|| self.handle_normal_help_input(event, view_state),
-			|| self.handle_visual_help_input(event, view_state),
+			|| self.normal_mode_help.handle_event(event, view_state),
+			|| self.visual_mode_help.handle_event(event, view_state),
 			|| self.handle_search_input(event)
 		)
 	}
@@ -590,20 +590,6 @@ impl List {
 		}
 	}
 
-	fn handle_normal_help_input(&mut self, event: Event, view_state: &crate::view::State) -> Option<Results> {
-		self.normal_mode_help.is_active().then(|| {
-			self.normal_mode_help.handle_event(event, view_state);
-			Results::new()
-		})
-	}
-
-	fn handle_visual_help_input(&mut self, event: Event, view_state: &crate::view::State) -> Option<Results> {
-		self.visual_mode_help.is_active().then(|| {
-			self.visual_mode_help.handle_event(event, view_state);
-			Results::new()
-		})
-	}
-
 	fn handle_search_input(&mut self, event: Event) -> Option<Results> {
 		if !self.search_bar.is_active() {
 			return None;

src/modules/show_commit.rs

@@ -136,42 +136,41 @@ impl Module for ShowCommit {
 	}
 
 	fn handle_event(&mut self, event: Event, view_state: &crate::view::State) -> Results {
-		if self.help.is_active() {
-			self.help.handle_event(event, view_state);
-			return Results::new();
-		}
-
-		let mut results = Results::new();
-
-		let active_view_data = match self.state {
-			ShowCommitState::Overview => &mut self.overview_view_data,
-			ShowCommitState::Diff => &mut self.diff_view_data,
-		};
-
-		if handle_view_data_scroll(event, view_state).is_none() {
-			match event {
-				Event::Standard(StandardEvent::ShowDiff) => {
-					active_view_data.update_view_data(|updater| updater.clear());
-					self.state = match self.state {
-						ShowCommitState::Overview => ShowCommitState::Diff,
-						ShowCommitState::Diff => ShowCommitState::Overview,
-					}
-				},
-				Event::Standard(StandardEvent::Help) => self.help.set_active(),
-				Event::Key(_) => {
-					active_view_data.update_view_data(|updater| updater.clear());
-					if self.state == ShowCommitState::Diff {
-						self.state = ShowCommitState::Overview;
-					}
-					else {
-						results.state(State::List);
-					}
-				},
-				Event::Resize(..) => active_view_data.update_view_data(|updater| updater.clear()),
-				_ => {},
-			}
-		}
-		results
+		select!(
+			default || {
+				let mut results = Results::new();
+
+				let active_view_data = match self.state {
+					ShowCommitState::Overview => &mut self.overview_view_data,
+					ShowCommitState::Diff => &mut self.diff_view_data,
+				};
+
+				match event {
+					Event::Standard(StandardEvent::ShowDiff) => {
+						active_view_data.update_view_data(|updater| updater.clear());
+						self.state = match self.state {
+							ShowCommitState::Overview => ShowCommitState::Diff,
+							ShowCommitState::Diff => ShowCommitState::Overview,
+						}
+					},
+					Event::Standard(StandardEvent::Help) => self.help.set_active(),
+					Event::Key(_) => {
+						active_view_data.update_view_data(|updater| updater.clear());
+						if self.state == ShowCommitState::Diff {
+							self.state = ShowCommitState::Overview;
+						}
+						else {
+							results.state(State::List);
+						}
+					},
+					Event::Resize(..) => active_view_data.update_view_data(|updater| updater.clear()),
+					_ => {},
+				}
+				results
+			},
+			|| self.help.handle_event(event, view_state),
+			|| handle_view_data_scroll(event, view_state)
+		)
 	}
 }
 

src/util.rs

@@ -1,4 +1,7 @@
-use crate::input::{Event, StandardEvent};
+use crate::{
+	input::{Event, StandardEvent},
+	process::Results,
+};
 
 #[macro_export]
 macro_rules! select {
@@ -23,19 +26,9 @@ macro_rules! select {
 	};
 }
 
-#[macro_export]
-macro_rules! first {
-	($first: expr, $($arg:expr),*) => {
-		if $first().is_some() {
-		}
-		$(else if $arg().is_some() {
-		})*
-	};
-}
-
 /// Utility function to handle scroll events.
 #[must_use]
-pub(crate) fn handle_view_data_scroll(event: Event, view_state: &crate::view::State) -> Option<Event> {
+pub(crate) fn handle_view_data_scroll(event: Event, view_state: &crate::view::State) -> Option<Results> {
 	match event {
 		Event::Standard(StandardEvent::ScrollLeft) => view_state.scroll_left(),
 		Event::Standard(StandardEvent::ScrollRight) => view_state.scroll_right(),
@@ -47,12 +40,13 @@ pub(crate) fn handle_view_data_scroll(event: Event, view_state: &crate::view::St
 		Event::Standard(StandardEvent::ScrollJumpUp) => view_state.scroll_page_up(),
 		_ => return None,
 	};
-	Some(event)
+	Some(Results::new())
 }
 
 #[cfg(test)]
 mod tests {
 	use captur::capture;
+	use claims::{assert_none, assert_some};
 	use rstest::rstest;
 
 	use super::*;
@@ -71,7 +65,7 @@ mod tests {
 		with_view_state(|context| {
 			capture!(action);
 			let event = Event::from(meta_event);
-			assert_eq!(handle_view_data_scroll(event, &context.state), Some(event));
+			assert_some!(handle_view_data_scroll(event, &context.state));
 			context.assert_render_action(&[action]);
 		});
 	}
@@ -80,7 +74,7 @@ mod tests {
 	fn handle_view_data_scroll_event_other() {
 		with_view_state(|context| {
 			let event = Event::from('a');
-			assert!(handle_view_data_scroll(event, &context.state).is_none());
+			assert_none!(handle_view_data_scroll(event, &context.state));
 			context.assert_render_action(&[]);
 		});
 	}