Allow customizing line break visualization (#1904)

Author: yamgent

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Added
+* `theme.ron` now supports customizing line break symbol ([#1894](https://github.com/extrawurst/gitui/issues/1894))
+
 ## [0.24.3] - 2023-09-09
 
 ### Fixes

THEMES.md

@@ -31,3 +31,21 @@ Notes:
 * using a color like `yellow` might appear in whatever your terminal/theme defines for `yellow`
 * valid colors can be found in tui-rs' [Color](https://docs.rs/tui/0.12.0/tui/style/enum.Color.html) struct. 
 * all customizable theme elements can be found in [`style.rs` in the `impl Default for Theme` block](https://github.com/extrawurst/gitui/blob/master/src/ui/style.rs#L305)
+
+## Customizing line breaks
+
+If you want to change how the line break is displayed in the diff, you can also specify `line_break` in your `theme.ron`:
+
+```
+(
+    line_break: Some("¶"),
+)
+```
+
+Note that if you want to turn it off, you should use a blank string:
+
+```
+(
+    line_break: Some(""),
+)
+```

src/components/diff.rs

@@ -462,7 +462,7 @@ impl DiffComponent {
 
 		let content =
 			if !is_content_line && line.content.as_ref().is_empty() {
-				String::from(strings::symbol::LINE_BREAK)
+				theme.line_break()
 			} else {
 				tabs_to_spaces(line.content.as_ref().to_string())
 			};
@@ -958,3 +958,75 @@ impl Component for DiffComponent {
 		self.focused = focus;
 	}
 }
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use crate::ui::style::Theme;
+	use std::io::Write;
+	use std::rc::Rc;
+	use tempfile::NamedTempFile;
+
+	#[test]
+	fn test_line_break() {
+		let diff_line = DiffLine {
+			content: "".into(),
+			line_type: DiffLineType::Add,
+			position: Default::default(),
+		};
+
+		{
+			let default_theme = Rc::new(Theme::default());
+
+			assert_eq!(
+				DiffComponent::get_line_to_add(
+					4,
+					&diff_line,
+					false,
+					false,
+					false,
+					&default_theme,
+					0
+				)
+				.spans
+				.last()
+				.unwrap(),
+				&Span::styled(
+					Cow::from("¶\n"),
+					default_theme
+						.diff_line(diff_line.line_type, false)
+				)
+			);
+		}
+
+		{
+			let mut file = NamedTempFile::new().unwrap();
+
+			writeln!(
+				file,
+				r#"
+(
+	line_break: Some("+")
+)
+"#
+			)
+			.unwrap();
+
+			let theme =
+				Rc::new(Theme::init(&file.path().to_path_buf()));
+
+			assert_eq!(
+				DiffComponent::get_line_to_add(
+					4, &diff_line, false, false, false, &theme, 0
+				)
+				.spans
+				.last()
+				.unwrap(),
+				&Span::styled(
+					Cow::from("+\n"),
+					theme.diff_line(diff_line.line_type, false)
+				)
+			);
+		}
+	}
+}

src/main.rs

@@ -157,7 +157,7 @@ fn main() -> Result<()> {
 		let quit_state = run_app(
 			app_start,
 			repo_path.clone(),
-			theme,
+			theme.clone(),
 			key_config.clone(),
 			&input,
 			updater,

src/strings.rs

@@ -42,7 +42,6 @@ pub mod symbol {
 	pub const CHECKMARK: &str = "\u{2713}"; //✓
 	pub const SPACE: &str = "\u{02FD}"; //˽
 	pub const EMPTY_SPACE: &str = " ";
-	pub const LINE_BREAK: &str = "¶";
 	pub const FOLDER_ICON_COLLAPSED: &str = "\u{25b8}"; //▸
 	pub const FOLDER_ICON_EXPANDED: &str = "\u{25be}"; //▾
 	pub const EMPTY_STR: &str = "";

src/ui/style.rs

@@ -8,7 +8,7 @@ use struct_patch::Patch;
 
 pub type SharedTheme = Rc<Theme>;
 
-#[derive(Serialize, Deserialize, Debug, Copy, Clone, Patch)]
+#[derive(Serialize, Deserialize, Debug, Clone, Patch)]
 #[patch_derive(Serialize, Deserialize)]
 pub struct Theme {
 	selected_tab: Color,
@@ -32,6 +32,7 @@ pub struct Theme {
 	push_gauge_fg: Color,
 	tag_fg: Color,
 	branch_fg: Color,
+	line_break: String,
 }
 
 impl Theme {
@@ -192,6 +193,10 @@ impl Theme {
 		Style::default().fg(self.danger_fg)
 	}
 
+	pub fn line_break(&self) -> String {
+		self.line_break.clone()
+	}
+
 	pub fn commandbar(&self, enabled: bool, line: usize) -> Style {
 		if enabled {
 			Style::default().fg(self.command_fg)
@@ -278,7 +283,7 @@ impl Theme {
 	// This is supposed to be called when theme.ron doesn't already exists.
 	fn save_patch(&self, theme_path: &PathBuf) -> Result<()> {
 		let mut file = File::create(theme_path)?;
-		let patch = self.into_patch_by_diff(Self::default());
+		let patch = self.clone().into_patch_by_diff(Self::default());
 		let data = to_string_pretty(&patch, PrettyConfig::default())?;
 
 		file.write_all(data.as_bytes())?;
@@ -336,6 +341,7 @@ impl Default for Theme {
 			push_gauge_fg: Color::Reset,
 			tag_fg: Color::LightMagenta,
 			branch_fg: Color::LightYellow,
+			line_break: "¶".to_string(),
 		}
 	}
 }